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Mahamar A, Smit MJ, Sanogo K, Sinaba Y, Niambele SM, Sacko A, Dicko OM, Diallo M, Maguiraga SO, Sankaré Y, Keita S, Samake S, Dembele A, Lanke K, Ter Heine R, Bradley J, Dicko Y, Traore SF, Drakeley C, Dicko A, Bousema T, Stone W. Artemether-lumefantrine with or without single-dose primaquine and sulfadoxine-pyrimethamine plus amodiaquine with or without single-dose tafenoquine to reduce Plasmodium falciparum transmission: a phase 2, single-blind, randomised clinical trial in Ouelessebougou, Mali. Lancet Microbe 2024:S2666-5247(24)00023-5. [PMID: 38705163 DOI: 10.1016/s2666-5247(24)00023-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 12/21/2023] [Accepted: 01/17/2024] [Indexed: 05/07/2024]
Abstract
BACKGROUND Artemether-lumefantrine is widely used for uncomplicated Plasmodium falciparum malaria; sulfadoxine-pyrimethamine plus amodiaquine is used for seasonal malaria chemoprevention. We aimed to determine the efficacy of artemether-lumefantrine with and without primaquine and sulfadoxine-pyrimethamine plus amodiaquine with and without tafenoquine for reducing gametocyte carriage and transmission to mosquitoes. METHODS In this phase 2, single-blind, randomised clinical trial conducted in Ouelessebougou, Mali, asymptomatic individuals aged 10-50 years with P falciparum gametocytaemia were recruited from the community and randomly assigned (1:1:1:1) to receive either artemether-lumefantrine, artemether-lumefantrine with a single dose of 0·25 mg/kg primaquine, sulfadoxine-pyrimethamine plus amodiaquine, or sulfadoxine-pyrimethamine plus amodiaquine with a single dose of 1·66 mg/kg tafenoquine. All trial staff other than the pharmacist were masked to group allocation. Participants were not masked to group allocation. Randomisation was done with a computer-generated randomisation list and concealed with sealed, opaque envelopes. The primary outcome was the median within-person percent change in mosquito infection rate in infectious individuals from baseline to day 2 (artemether-lumefantrine groups) or day 7 (sulfadoxine-pyrimethamine plus amodiaquine groups) after treatment, assessed by direct membrane feeding assay. All participants who received any trial drug were included in the safety analysis. This study is registered with ClinicalTrials.gov, NCT05081089. FINDINGS Between Oct 13 and Dec 16, 2021, 1290 individuals were screened and 80 were enrolled and randomly assigned to one of the four treatment groups (20 per group). The median age of participants was 13 (IQR 11-20); 37 (46%) of 80 participants were female and 43 (54%) were male. In individuals who were infectious before treatment, the median percentage reduction in mosquito infection rate 2 days after treatment was 100·0% (IQR 100·0-100·0; n=19; p=0·0011) with artemether-lumefantrine and 100·0% (100·0-100·0; n=19; p=0·0001) with artemether-lumefantrine with primaquine. Only two individuals who were infectious at baseline infected mosquitoes on day 2 after artemether-lumefantrine and none at day 5. By contrast, the median percentage reduction in mosquito infection rate 7 days after treatment was 63·6% (IQR 0·0-100·0; n=20; p=0·013) with sulfadoxine-pyrimethamine plus amodiaquine and 100% (100·0-100·0; n=19; p<0·0001) with sulfadoxine-pyrimethamine plus amodiaquine with tafenoquine. No grade 3-4 or serious adverse events occurred. INTERPRETATION These data support the effectiveness of artemether-lumefantrine alone for preventing nearly all mosquito infections. By contrast, there was considerable post-treatment transmission after sulfadoxine-pyrimethamine plus amodiaquine; therefore, the addition of a transmission-blocking drug might be beneficial in maximising its community impact. FUNDING Bill & Melinda Gates Foundation.
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Affiliation(s)
- Almahamoudou Mahamar
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali.
| | - Merel J Smit
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
| | - Koualy Sanogo
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Youssouf Sinaba
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sidi M Niambele
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Adama Sacko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Oumar M Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Makonon Diallo
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Seydina O Maguiraga
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Yaya Sankaré
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekouba Keita
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Siaka Samake
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Adama Dembele
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Kjerstin Lanke
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
| | - Rob Ter Heine
- Department of Pharmacy and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
| | - John Bradley
- MRC International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
| | - Yahia Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekou F Traore
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Chris Drakeley
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - Alassane Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Teun Bousema
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
| | - Will Stone
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, UK
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2
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Schmit N, Topazian HM, Natama HM, Bellamy D, Traoré O, Somé MA, Rouamba T, Tahita MC, Bonko MDA, Sourabié A, Sorgho H, Stockdale L, Provstgaard-Morys S, Aboagye J, Woods D, Rapi K, Datoo MS, Lopez FR, Charles GD, McCain K, Ouedraogo JB, Hamaluba M, Olotu A, Dicko A, Tinto H, Hill AVS, Ewer KJ, Ghani AC, Winskill P. The public health impact and cost-effectiveness of the R21/Matrix-M malaria vaccine: a mathematical modelling study. Lancet Infect Dis 2024; 24:465-475. [PMID: 38342107 DOI: 10.1016/s1473-3099(23)00816-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 12/18/2023] [Accepted: 12/18/2023] [Indexed: 02/13/2024]
Abstract
BACKGROUND The R21/Matrix-M vaccine has demonstrated high efficacy against Plasmodium falciparum clinical malaria in children in sub-Saharan Africa. Using trial data, we aimed to estimate the public health impact and cost-effectiveness of vaccine introduction across sub-Saharan Africa. METHODS We fitted a semi-mechanistic model of the relationship between anti-circumsporozoite protein antibody titres and vaccine efficacy to data from 3 years of follow-up in the phase 2b trial of R21/Matrix-M in Nanoro, Burkina Faso. We validated the model by comparing predicted vaccine efficacy to that observed over 12-18 months in the phase 3 trial. Integrating this framework within a mathematical transmission model, we estimated the cases, malaria deaths, and disability-adjusted life-years (DALYs) averted and cost-effectiveness over a 15-year time horizon across a range of transmission settings in sub-Saharan Africa. Cost-effectiveness was estimated incorporating the cost of vaccine introduction (dose, consumables, and delivery) relative to existing interventions at baseline. We report estimates at a median of 20% parasite prevalence in children aged 2-10 years (PfPR2-10) and ranges from 3% to 65% PfPR2-10. FINDINGS Anti-circumsporozoite protein antibody titres were found to satisfy the criteria for a surrogate of protection for vaccine efficacy against clinical malaria. Age-based implementation of a four-dose regimen of R21/Matrix-M vaccine was estimated to avert 181 825 (range 38 815-333 491) clinical cases per 100 000 fully vaccinated children in perennial settings and 202 017 (29 868-405 702) clinical cases per 100 000 fully vaccinated children in seasonal settings. Similar estimates were obtained for seasonal or hybrid implementation. Under an assumed vaccine dose price of US$3, the incremental cost per clinical case averted was $7 (range 4-48) in perennial settings and $6 (3-63) in seasonal settings and the incremental cost per DALY averted was $34 (29-139) in perennial settings and $30 (22-172) in seasonal settings, with lower cost-effectiveness ratios in settings with higher PfPR2-10. INTERPRETATION Introduction of the R21/Matrix-M malaria vaccine could have a substantial public health benefit across sub-Saharan Africa. FUNDING The Wellcome Trust, the Bill & Melinda Gates Foundation, the UK Medical Research Council, the European and Developing Countries Clinical Trials Partnership 2 and 3, the NIHR Oxford Biomedical Research Centre, and the Serum Institute of India, Open Philanthropy.
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Affiliation(s)
- Nora Schmit
- UK Medical Research Council Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, UK.
| | - Hillary M Topazian
- UK Medical Research Council Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, UK
| | - H Magloire Natama
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Duncan Bellamy
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Ousmane Traoré
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - M Athanase Somé
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Toussaint Rouamba
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Marc Christian Tahita
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Massa Dit Achille Bonko
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Aboubakary Sourabié
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Hermann Sorgho
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Lisa Stockdale
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | | | - Jeremy Aboagye
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Danielle Woods
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Katerina Rapi
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Mehreen S Datoo
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | | | - Giovanni D Charles
- UK Medical Research Council Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, UK
| | - Kelly McCain
- UK Medical Research Council Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, UK
| | - Jean-Bosco Ouedraogo
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso; Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Mainga Hamaluba
- Centre for Geographic Medicine Research (Coast), Kenya Medical Research Institute-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Ally Olotu
- Clinical Trials and Interventions Unit, Ifakara Health Institute, Bagamoyo, Tanzania
| | - Alassane Dicko
- The Malaria Research and Training Centre, University of Science, Technology, and Techniques of Bamako, Bamako, Mali
| | - Halidou Tinto
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso; Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Adrian V S Hill
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Katie J Ewer
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK; GSK Vaccines Institute for Global Health (Global Health Vaccines R&D), GSK, Siena, Italy
| | - Azra C Ghani
- UK Medical Research Council Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, UK
| | - Peter Winskill
- UK Medical Research Council Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, UK
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3
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Djimde M, Arama C, Koné B, Diakité H, Keita M, Samaké MD, Tembely B, Bagayoko B, Traoré MB, Tshiongo JK, Mavoko HM, Dicko A, Vaillant M, Mens PF, Schallig HD, Kayentao K. Assessment of the impact of pregnancy and malaria infection on the variation of neutrophil levels in women from San, Mali. J Infect Dev Ctries 2024; 18:627-635. [PMID: 38728650 DOI: 10.3855/jidc.18409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 09/14/2023] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND In patients with severe neutropenia, infections can rapidly become serious and life-threatening. It is essential to understand whether pregnancy induces changes in neutrophil levels thereby posing an increased threat to the health of gravidae. METHODOLOGY This cross-sectional study was conducted in San Health District (Mali) and involved pregnant women infected or not by malaria parasites and non-pregnant healthy volunteers. Subjects were categorized as having neutropenia, normal neutrophil levels, and neutrophilia regarding their neutrophil levels. A logistic regression analysis was performed to determine factors associated with neutrophil level variation in pregnant women. RESULTS Whether or not the pregnant women were infected with malaria, 98 of the 202 cases (48.5%) showed neutrophilia. Surprisingly, 67 of the 71 cases of neutropenia (94.4%) observed in this study concerned healthy people who were not pregnant. The mean percentage of neutrophil levels was significantly (p < 0.001) lower (49.9%) in the first trimester compared to the second trimester of pregnancy (62.0%). A logistic regression model showed that compared to early pregnancy, the second (OR = 12.9, 95% CI 2.2-248.1, p = 0.018) and the third trimesters (OR = 13.7, 95% CI 2.3-257.5, p = 0.016) were strongly associated with the increase of neutrophil levels. CONCLUSIONS Pregnancy can induce the production of mature neutrophils that are continually released into circulation. Neutrophil levels were lower during the first trimester of the pregnancy compared to the second and third trimesters, but not affected by the presence or absence of malaria infection.
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Affiliation(s)
- Moussa Djimde
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Charles Arama
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Bouréma Koné
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Hamadoun Diakité
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Mohamed Keita
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Mamadou D Samaké
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Bréhima Tembely
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Balla Bagayoko
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Mohamed B Traoré
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Japhet K Tshiongo
- Department of Tropical Medicine, University of Kinshasa (UNIKIN), Kinshasa, Democratic Republic of the Congo
| | - Hypolite M Mavoko
- Department of Tropical Medicine, University of Kinshasa (UNIKIN), Kinshasa, Democratic Republic of the Congo
| | - Alassane Dicko
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Michel Vaillant
- Centre of Competence for Methodology and Statistics (CCMS), Luxembourg Institute of Health (LIH), Strassen, Luxembourg
| | - Petra F Mens
- Amsterdam University Medical Centres, Academic Medical Centre at the University of Amsterdam (AMC), Department of Medical Microbiology and Infection Prevention, Laboratory for Experimental Parasitology, Amsterdam, Netherlands
| | - Henk Dfh Schallig
- Amsterdam Institute for Infection and Immunity, Infectious Diseases Programme, Amsterdam, Netherlands
| | - Kassoum Kayentao
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
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4
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Datoo MS, Dicko A, Tinto H, Ouédraogo JB, Hamaluba M, Olotu A, Beaumont E, Ramos Lopez F, Natama HM, Weston S, Chemba M, Compaore YD, Issiaka D, Salou D, Some AM, Omenda S, Lawrie A, Bejon P, Rao H, Chandramohan D, Roberts R, Bharati S, Stockdale L, Gairola S, Greenwood BM, Ewer KJ, Bradley J, Kulkarni PS, Shaligram U, Hill AVS. Safety and efficacy of malaria vaccine candidate R21/Matrix-M in African children: a multicentre, double-blind, randomised, phase 3 trial. Lancet 2024; 403:533-544. [PMID: 38310910 DOI: 10.1016/s0140-6736(23)02511-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 10/22/2023] [Accepted: 11/06/2023] [Indexed: 02/06/2024]
Abstract
BACKGROUND Recently, we found that a new malaria vaccine, R21/Matrix-M, had over 75% efficacy against clinical malaria with seasonal administration in a phase 2b trial in Burkina Faso. Here, we report on safety and efficacy of the vaccine in a phase 3 trial enrolling over 4800 children across four countries followed for up to 18 months at seasonal sites and 12 months at standard sites. METHODS We did a double-blind, randomised, phase 3 trial of the R21/Matrix-M malaria vaccine across five sites in four African countries with differing malaria transmission intensities and seasonality. Children (aged 5-36 months) were enrolled and randomly assigned (2:1) to receive 5 μg R21 plus 50 μg Matrix-M or a control vaccine (licensed rabies vaccine [Abhayrab]). Participants, their families, investigators, laboratory teams, and the local study team were masked to treatment. Vaccines were administered as three doses, 4 weeks apart, with a booster administered 12 months after the third dose. Half of the children were recruited at two sites with seasonal malaria transmission and the remainder at standard sites with perennial malaria transmission using age-based immunisation. The primary objective was protective efficacy of R21/Matrix-M from 14 days after third vaccination to 12 months after completion of the primary series at seasonal and standard sites separately as co-primary endpoints. Vaccine efficacy against multiple malaria episodes and severe malaria, as well as safety and immunogenicity, were also assessed. This trial is registered on ClinicalTrials.gov, NCT04704830, and is ongoing. FINDINGS From April 26, 2021, to Jan 12, 2022, 5477 children consented to be screened, of whom 1705 were randomly assigned to control vaccine and 3434 to R21/Matrix-M; 4878 participants received the first dose of vaccine. 3103 participants in the R21/Matrix-M group and 1541 participants in the control group were included in the modified per-protocol analysis (2412 [51·9%] male and 2232 [48·1%] female). R21/Matrix-M vaccine was well tolerated, with injection site pain (301 [18·6%] of 1615 participants) and fever (754 [46·7%] of 1615 participants) as the most frequent adverse events. Number of adverse events of special interest and serious adverse events did not significantly differ between the vaccine groups. There were no treatment-related deaths. 12-month vaccine efficacy was 75% (95% CI 71-79; p<0·0001) at the seasonal sites and 68% (61-74; p<0·0001) at the standard sites for time to first clinical malaria episode. Similarly, vaccine efficacy against multiple clinical malaria episodes was 75% (71-78; p<0·0001) at the seasonal sites and 67% (59-73; p<0·0001) at standard sites. A modest reduction in vaccine efficacy was observed over the first 12 months of follow-up, of similar size at seasonal and standard sites. A rate reduction of 868 (95% CI 762-974) cases per 1000 children-years at seasonal sites and 296 (231-362) at standard sites occurred over 12 months. Vaccine-induced antibodies against the conserved central Asn-Ala-Asn-Pro (NANP) repeat sequence of circumsporozoite protein correlated with vaccine efficacy. Higher NANP-specific antibody titres were observed in the 5-17 month age group compared with 18-36 month age group, and the younger age group had the highest 12-month vaccine efficacy on time to first clinical malaria episode at seasonal (79% [95% CI 73-84]; p<0·001) and standard (75% [65-83]; p<0·001) sites. INTERPRETATION R21/Matrix-M was well tolerated and offered high efficacy against clinical malaria in African children. This low-cost, high-efficacy vaccine is already licensed by several African countries, and recently received a WHO policy recommendation and prequalification, offering large-scale supply to help reduce the great burden of malaria in sub-Saharan Africa. FUNDING The Serum Institute of India, the Wellcome Trust, the UK National Institute for Health Research Oxford Biomedical Research Centre, and Open Philanthropy.
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Affiliation(s)
- Mehreen S Datoo
- Centre for Clinical Vaccinology and Tropical Medicine, The Jenner Institute, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Alassane Dicko
- Clinical Research Unit of Bougouni-Ouelessebougou, Malaria Research and Training Centre, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Halidou Tinto
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | | | - Mainga Hamaluba
- Kenya Medical Research Institute Centre for Geographical Medicine Research-Coast (KEMRI-CGMRC), Kilifi, Kenya; Centre for Tropical Medicine & Global Health, Nuffield Department of Medicine, Oxford, UK
| | - Ally Olotu
- Ifakara Health Institute, Bagamoyo Research and Training Centre, Bagamoyo, Tanzania
| | - Emma Beaumont
- London School of Hygiene and Tropical Medicine, London, UK
| | - Fernando Ramos Lopez
- Centre for Clinical Vaccinology and Tropical Medicine, The Jenner Institute, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Hamtandi Magloire Natama
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Sophie Weston
- Centre for Clinical Vaccinology and Tropical Medicine, The Jenner Institute, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Mwajuma Chemba
- Ifakara Health Institute, Bagamoyo Research and Training Centre, Bagamoyo, Tanzania
| | | | - Djibrilla Issiaka
- Clinical Research Unit of Bougouni-Ouelessebougou, Malaria Research and Training Centre, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Diallo Salou
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Athanase M Some
- Unité de Recherche Clinique de Nanoro, Institut de Recherche en Sciences de la Santé, Nanoro, Burkina Faso
| | - Sharon Omenda
- Kenya Medical Research Institute Centre for Geographical Medicine Research-Coast (KEMRI-CGMRC), Kilifi, Kenya
| | - Alison Lawrie
- Centre for Clinical Vaccinology and Tropical Medicine, The Jenner Institute, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Philip Bejon
- Kenya Medical Research Institute Centre for Geographical Medicine Research-Coast (KEMRI-CGMRC), Kilifi, Kenya
| | | | | | - Rachel Roberts
- Centre for Clinical Vaccinology and Tropical Medicine, The Jenner Institute, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK
| | | | - Lisa Stockdale
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | | | | | - Katie J Ewer
- The Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - John Bradley
- London School of Hygiene and Tropical Medicine, London, UK
| | | | | | - Adrian V S Hill
- Centre for Clinical Vaccinology and Tropical Medicine, The Jenner Institute, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK; The Jenner Institute Laboratories, University of Oxford, Oxford, UK.
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5
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Attaher O, Swihart B, Dang L, Santara G, Mahamar A, Keita S, Dembele A, Diarra BS, Issiaka D, Barry A, Sidibé Y, Dicko YT, Traore S, Koita F, Ndiaye O, Dicko A, Kurtis JD, Duffy PE, Fried M. Higher platelet counts and platelet factors are associated with a reduction in Plasmodium falciparum parasite density in young Malian children. Int J Infect Dis 2024; 139:171-175. [PMID: 38114057 PMCID: PMC10928852 DOI: 10.1016/j.ijid.2023.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/14/2023] [Accepted: 12/15/2023] [Indexed: 12/21/2023] Open
Abstract
OBJECTIVES The association between thrombocytopenia and parasite density or disease severity is described in numerous studies. In recent years, several studies described the protective role of platelets in directly killing Plasmodium parasites, mediated by platelet factor 4 (PF4) binding to Duffy antigen. This study aimed to evaluate the protective role of platelets in young children who are Duffy antigen-negative, such as those in sub-Saharan Africa. METHODS A zero-inflated negative binomial model was used to relate platelet count and parasite density data collected in a longitudinal birth cohort. Platelet factors were measured by enzyme-linked immunosorbent assay in samples collected from malaria-infected children who participated in a cross-sectional study. RESULTS We described that an increase of 10,000 platelets/μl was associated with a 2.76% reduction in parasite count. Increasing levels of PF4 and CXCL7 levels were also significantly associated with a reduction in parasite count. CONCLUSIONS Platelets play a protective role in reducing parasite burden in Duffy-negative children, possibly mediated through activation of the innate immune system.
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Affiliation(s)
- Oumar Attaher
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Bruce Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
| | - Lauren Dang
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
| | - Gaoussou Santara
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Almahamoudou Mahamar
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekouba Keita
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Adama Dembele
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Bacary Soumana Diarra
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Djibrilla Issiaka
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Amadou Barry
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Youssoufa Sidibé
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Yahia T Dicko
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Seydou Traore
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Fanta Koita
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Ouelematou Ndiaye
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Jonathan D Kurtis
- Center for International Health Research, Rhode Island Hospital, Brown University Medical School, Providence, Rhode Island, USA; Department of Pathology and Laboratory Medicine, Brown University Medical School, Providence, Rhode Island, USA
| | - Patrick E Duffy
- Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Michal Fried
- Molecular and Pathogenesis Biomarkers Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.
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6
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Mahamar A, Traore M, Swihart B, Attaher O, Diarra BS, Santara G, Issiaka D, Barry A, Sidibé Y, Dicko YT, Keita S, Ndiaye O, Dicko A, Duffy PE, Fried M. Acquisition of antibodies that block Plasmodium falciparum adhesion to placental receptor chondroitin sulfate A with increasing gravidity in Malian women. Front Immunol 2024; 14:1330962. [PMID: 38274790 PMCID: PMC10808177 DOI: 10.3389/fimmu.2023.1330962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 12/20/2023] [Indexed: 01/27/2024] Open
Abstract
In malaria-endemic areas, pregnant women are more susceptible to Plasmodium falciparum infection, especially primigravidae. During pregnancy, parasites sequester in the placenta and bind to the receptor chondroitin sulfate (CSA). This unique adhesion is mediated by the parasite protein VAR2CSA expressed on the surface of infected erythrocytes (IE). Placental malaria is associated with poor pregnancy outcomes including perinatal mortality, preterm delivery, small for gestational age (SGA) and low birthweight deliveries. Over successive pregnancies, women acquire functional antibodies that inhibit IE adhesion to CSA. Here, we examine the development of anti-adhesion activity and the breadth of anti-adhesion activity as a function of number of previous pregnancies, using samples collected from pregnant women living in an area with high seasonal malaria transmission. Women reached plateau levels of anti-adhesion activity and breadth of anti-adhesion activity after 5 pregnancies. We related the level of anti-adhesion activity and reactivity with surface IE to SGA 19/232 pregnancies resulted in SGA, and report that an increase of 10% in median anti-adhesion activity reduced the odds of SGA by 13% and this relationship approached significance. Further, at an anti-adhesion activity level of 43.7%, an increase of 10% in the breadth of activity significantly reduced the odds of SGA by 21.5%. Antibodies that recognize IE surface increased over successive pregnancies, but were not associated with a reduction in SGA. These results can serve as a guideline for assessing vaccine candidates aiming to reduce poor pregnancy outcomes associated with placental malaria.
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Affiliation(s)
- Almahamoudou Mahamar
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Moussa Traore
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Bruce Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, NIH, Rockville, MD, United States
| | - Oumar Attaher
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Bacary Soumana Diarra
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Gaoussou Santara
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Djibrilla Issiaka
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Amadou Barry
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Youssoufa Sidibé
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Yahia T. Dicko
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekouba Keita
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Oulematou Ndiaye
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Patrick E. Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, United States
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, United States
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7
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Dicko A, Ouedraogo JB, Zongo I, Sagara I, Cairns M, Yerbanga RS, Issiaka D, Zoungrana C, Sidibe Y, Tapily A, Nikièma F, Sompougdou F, Sanogo K, Kaya M, Yalcouye H, Dicko OM, Diarra M, Diarra K, Thera I, Haro A, Sienou AA, Traore S, Mahamar A, Dolo A, Kuepfer I, Snell P, Grant J, Webster J, Milligan P, Lee C, Ockenhouse C, Ofori-Anyinam O, Tinto H, Djimde A, Chandramohan D, Greenwood B. Seasonal vaccination with RTS,S/AS01 E vaccine with or without seasonal malaria chemoprevention in children up to the age of 5 years in Burkina Faso and Mali: a double-blind, randomised, controlled, phase 3 trial. Lancet Infect Dis 2024; 24:75-86. [PMID: 37625434 DOI: 10.1016/s1473-3099(23)00368-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/31/2023] [Accepted: 06/01/2023] [Indexed: 08/27/2023]
Abstract
BACKGROUND Seasonal vaccination with the RTS,S/AS01E vaccine combined with seasonal malaria chemoprevention (SMC) prevented malaria in young children more effectively than either intervention given alone over a 3 year period. The objective of this study was to establish whether the added protection provided by the combination could be sustained for a further 2 years. METHODS This was a double-blind, individually randomised, controlled, non-inferiority and superiority, phase 3 trial done at two sites: the Bougouni district and neighbouring areas in Mali and Houndé district, Burkina Faso. Children who had been enrolled in the initial 3-year trial when aged 5-17 months were initially randomly assigned individually to receive SMC with sulphadoxine-pyrimethamine and amodiaquine plus control vaccines, RTS,S/AS01E plus placebo SMC, or SMC plus RTS,S/AS01E. They continued to receive the same interventions until the age of 5 years. The primary trial endpoint was the incidence of clinical malaria over the 5-year trial period in both the modified intention-to-treat and per-protocol populations. Over the 5-year period, non-inferiority was defined as a 20% increase in clinical malaria in the RTS,S/AS01E-alone group compared with the SMC alone group. Superiority was defined as a 12% difference in the incidence of clinical malaria between the combined and single intervention groups. The study is registered with ClinicalTrials.gov, NCT04319380, and is complete. FINDINGS In April, 2020, of 6861 children originally recruited, 5098 (94%) of the 5433 children who completed the initial 3-year follow-up were re-enrolled in the extension study. Over 5 years, the incidence of clinical malaria per 1000 person-years at risk was 313 in the SMC alone group, 320 in the RTS,S/AS01E-alone group, and 133 in the combined group. The combination of RTS,S/AS01E and SMC was superior to SMC (protective efficacy 57·7%, 95% CI 53·3 to 61·7) and to RTS,S/AS01E (protective efficacy 59·0%, 54·7 to 62·8) in preventing clinical malaria. RTS,S/AS01E was non-inferior to SMC (hazard ratio 1·03 [95% CI 0·95 to 1·12]). The protective efficacy of the combination versus SMC over the 5-year period of the study was very similar to that seen in the first 3 years with the protective efficacy of the combination versus SMC being 57·7% (53·3 to 61·7) and versus RTS/AS01E-alone being 59·0% (54·7 to 62·8). The comparable figures for the first 3 years of the study were 62·8% (58·4 to 66·8) and 59·6% (54·7 to 64·0%), respectively. Hospital admissions for WHO-defined severe malaria were reduced by 66·8% (95% CI 40·3 to 81·5), for malarial anaemia by 65·9% (34·1 to 82·4), for blood transfusion by 68·1% (32·6 to 84·9), for all-cause deaths by 44·5% (2·8 to 68·3), for deaths excluding external causes or surgery by 41·1% (-9·2 to 68·3), and for deaths from malaria by 66·8% (-2·7 to 89·3) in the combined group compared with the SMC alone group. No safety signals were detected. INTERPRETATION Substantial protection against malaria was sustained over 5 years by combining seasonal malaria vaccination with seasonal chemoprevention, offering a potential new approach to malaria control in areas with seasonal malaria transmission. FUNDING UK Joint Global Health Trials and PATH's Malaria Vaccine Initiative (through a grant from the Bill & Melinda Gates Foundation). TRANSLATION For the French translation of the abstract see Supplementary Materials section.
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Affiliation(s)
- Alassane Dicko
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Jean-Bosco Ouedraogo
- Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Issaka Zongo
- Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Issaka Sagara
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Matthew Cairns
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Rakiswendé Serge Yerbanga
- Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Djibrilla Issiaka
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Charles Zoungrana
- Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Youssoufa Sidibe
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Amadou Tapily
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Frédéric Nikièma
- Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Frédéric Sompougdou
- Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Koualy Sanogo
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Mahamadou Kaya
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Hama Yalcouye
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Oumar Mohamed Dicko
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Modibo Diarra
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Kalifa Diarra
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Ismaila Thera
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Alassane Haro
- Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Abdoul Aziz Sienou
- Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Seydou Traore
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Almahamoudou Mahamar
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Amagana Dolo
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Irene Kuepfer
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK
| | - Paul Snell
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Jane Grant
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK
| | - Jayne Webster
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK
| | - Paul Milligan
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | | | | | | | - Halidou Tinto
- Institut des Sciences et Techniques-Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Abdoulaye Djimde
- The Malaria Research and Training Center, University of Science, Technology and Techniques of Bamako, Bamako, Mali
| | - Daniel Chandramohan
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK
| | - Brian Greenwood
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK.
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Djimde M, Kayentao K, Tshiongo JK, Fofana B, Arama C, Sirima SB, Ouedraogo JB, Beavogui AH, Sagara I, Dicko A, Mens PF, Schallig HD, Djimde A. Variation in neutrophil levels and artemisinin-based combination therapy efficacy in West-Africa. J Infect Dev Ctries 2023; 17:1337-1345. [PMID: 37824364 DOI: 10.3855/jidc.17089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Accepted: 03/04/2023] [Indexed: 10/14/2023] Open
Abstract
INTRODUCTION Polymorphonuclear neutrophils (PMN) are involved in pathogen clearance by phagocytosis. However, the role of PMNs in the efficacy of artemisinin-based combination therapy (ACT) is poorly understood. METHODOLOGY In a prospective longitudinal in vivo study, neutrophil rates were compared with malaria carriage after treatment with different ACTs: Artemether - lumefantrine (AL), Artesunate - amodiaquine (ASAQ), Dihydroartemisinin - piperaquine (DP) or Pyronaridine artesunate (PA). The study cases were classified as having neutropenia, normal neutrophil levels or neutrophilia depending on the level of neutrophils in the blood. This study included 3148 patients and was analyzed using R. RESULTS On day 7, only four patients in the neutropenia group and treated with AL had a malaria positive blood smear based on microscopy. On day 28, the rate of recurrent parasitemia in the AL arm was significantly higher in neutropenia patients (50.9%) than in patients with normal rates of neutrophils (43.1%) or in those with neutrophilia (6.0%) (p < 0.001). In ASAQ arm, the rate of recurrent Plasmodium falciparum parasitemia was 58.8% in the neutropenia group versus 29.4% in patients with normal rates of neutrophils and 11.8% in patients with neutrophilia (p < 0.001). No patient treated with DP with normal neutrophil counts or neutrophilia was carrying malaria parasites on day 28. Among the 15 patients with parasitemia on day 28 in the PA arm, 11 (73.33%) had neutropenia while 4 (26.67%) had a normal neutrophil count (p < 0.001). CONCLUSIONS Patients with neutropenia had higher rates of recurrent P. falciparum parasitemia after ACT.
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Affiliation(s)
- Moussa Djimde
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Kassoum Kayentao
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Japhet Kabalu Tshiongo
- Department of Tropical Medicine, University of Kinshasa (UNIKIN), Kinshasa, Democratic Republic of the Congo
| | - Bakary Fofana
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Charles Arama
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Sodiomon B Sirima
- Groupe de Recherche Action en Santé (GRAS), Ouagadougou, Burkina Faso
| | - Jean Bosco Ouedraogo
- Institut des Sciences et des Techniques Bobo Dioulasso (INSTech-Bobo), Burkina Faso
| | - Abdoul Habib Beavogui
- Centre National de Formation et de Recherche en Santé Rurale (CNFRSR), Mafinrinha, Guinea
| | - Issaka Sagara
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Alassane Dicko
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
| | - Petra F Mens
- Amsterdam University Medical Centre, Academic Medical Centre at the University of Amsterdam (AMC), Amsterdam, The Netherlands
| | - Henk Dfh Schallig
- Amsterdam University Medical Centre, Academic Medical Centre at the University of Amsterdam (AMC), Amsterdam, The Netherlands
| | - Abdoulaye Djimde
- Malaria Research and Training Center (MRTC), University of Sciences of Techniques and Technologies of Bamako (USTTB), Mali
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9
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Vanheer LN, Mahamar A, Manko E, Niambele SM, Sanogo K, Youssouf A, Dembele A, Diallo M, Maguiraga SO, Phelan J, Osborne A, Spadar A, Smit MJ, Bousema T, Drakeley C, Clark TG, Stone W, Dicko A, Campino S. Genome-wide genetic variation and molecular surveillance of drug resistance in Plasmodium falciparum isolates from asymptomatic individuals in Ouélessébougou, Mali. Sci Rep 2023; 13:9522. [PMID: 37308503 DOI: 10.1038/s41598-023-36002-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 05/27/2023] [Indexed: 06/14/2023] Open
Abstract
Sequence analysis of Plasmodium falciparum parasites is informative in ensuring sustained success of malaria control programmes. Whole-genome sequencing technologies provide insights into the epidemiology and genome-wide variation of P. falciparum populations and can characterise geographical as well as temporal changes. This is particularly important to monitor the emergence and spread of drug resistant P. falciparum parasites which is threatening malaria control programmes world-wide. Here, we provide a detailed characterisation of genome-wide genetic variation and drug resistance profiles in asymptomatic individuals in South-Western Mali, where malaria transmission is intense and seasonal, and case numbers have recently increased. Samples collected from Ouélessébougou, Mali (2019-2020; n = 87) were sequenced and placed in the context of older Malian (2007-2017; n = 876) and African-wide (n = 711) P. falciparum isolates. Our analysis revealed high multiclonality and low relatedness between isolates, in addition to increased frequencies of molecular markers for sulfadoxine-pyrimethamine and lumefantrine resistance, compared to older Malian isolates. Furthermore, 21 genes under selective pressure were identified, including a transmission-blocking vaccine candidate (pfCelTOS) and an erythrocyte invasion locus (pfdblmsp2). Overall, our work provides the most recent assessment of P. falciparum genetic diversity in Mali, a country with the second highest burden of malaria in West Africa, thereby informing malaria control activities.
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Affiliation(s)
- Leen N Vanheer
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
| | - Almahamoudou Mahamar
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Emilia Manko
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Sidi M Niambele
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Koualy Sanogo
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Ahamadou Youssouf
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Adama Dembele
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Makonon Diallo
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Seydina O Maguiraga
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Jody Phelan
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Ashley Osborne
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Anton Spadar
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Merel J Smit
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Teun Bousema
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Chris Drakeley
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Taane G Clark
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK
| | - William Stone
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Alassane Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Susana Campino
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
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10
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Grant J, Diawara H, Traore S, Koita F, Myers J, Sagara I, Chandramohan D, Dicko A, Greenwood B, Webster J. Delivery strategies for malaria vaccination in areas with seasonal malaria transmission. BMJ Glob Health 2023; 8:e011838. [PMID: 37147016 PMCID: PMC10163455 DOI: 10.1136/bmjgh-2023-011838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 04/11/2023] [Indexed: 05/07/2023] Open
Abstract
BACKGROUND Seasonal vaccination with the RTS,S/AS01E malaria vaccine given alongside seasonal malaria chemoprevention (SMC) substantially reduces malaria in young children. The WHO has recommended the use of RTS,S/AS01E, including seasonal vaccination, in areas with seasonal malaria transmission. This study aimed to identify potential strategies to deliver RTS,S/AS01E, and assess the considerations and recommendations for delivery of seasonal malaria vaccination in Mali, a country with highly seasonal malaria. METHODS Potential delivery strategies for RTS,S/AS01E in areas with seasonal malaria were identified through a series of high level discussions with the RTS,S/AS01E plus SMC trial investigators, international and national immunisation and malaria experts, and through the development of a theory of change. These were explored through qualitative in-depth interviews with 108 participants, including national-level, regional-level and district-level malaria and immunisation programme managers, health workers, caregivers of children under 5 years of age, and community stakeholders. A national-level workshop was held to confirm the qualitative findings and work towards consensus on an appropriate strategy. RESULTS Four delivery strategies were identified: age-based vaccination delivered via the Essential Programme on Immunisation (EPI); seasonal vaccination via EPI mass vaccination campaigns (MVCs); a combination of age-based priming vaccination doses delivered via the EPI clinics and seasonal booster doses delivered via MVCs; and a combination of age-based priming vaccination doses and seasonal booster doses, all delivered via the EPI clinics, which was the preferred strategy for delivery of RTS,S/AS01E in Mali identified during the national workshop. Participants recommended that supportive interventions, including communications and mobilisation, would be needed for this strategy to achieve required coverage. CONCLUSIONS Four delivery strategies were identified for administration of RTS,S/AS01E alongside SMC in countries with seasonal malaria transmission. Components of these delivery strategies were defined as the vaccination schedule, and the delivery system(s) plus the supportive interventions needed for the strategies to be effective. Further implementation research and evaluation is needed to explore how, where, when and what effective coverage is achievable via these new strategies and their supportive interventions.
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Affiliation(s)
- Jane Grant
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Halimatou Diawara
- Malaria Research and Training Center (MRTC), Universite des Sciences des Techniques et des Technologies de Bamako, Bamako, Mali
| | - Seydou Traore
- Malaria Research and Training Center (MRTC), Universite des Sciences des Techniques et des Technologies de Bamako, Bamako, Mali
| | - Fatoumata Koita
- Malaria Research and Training Center (MRTC), Universite des Sciences des Techniques et des Technologies de Bamako, Bamako, Mali
| | - Jessica Myers
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Issaka Sagara
- Malaria Research and Training Center (MRTC), Universite des Sciences des Techniques et des Technologies de Bamako, Bamako, Mali
| | - Daniel Chandramohan
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Alassane Dicko
- Malaria Research and Training Center (MRTC), Universite des Sciences des Techniques et des Technologies de Bamako, Bamako, Mali
| | - Brian Greenwood
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Jayne Webster
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
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11
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Diawara H, Bocoum FY, Dicko A, Levin A, Lee C, Koita F, Ouédraogo JB, Guissou R, Yabré S, Traoré S, Morgan W, Pecenka C, Baral R. Cost of introducing and delivering malaria vaccine (RTS,S/AS01 E) in areas of seasonal malaria transmission, Mali and Burkina Faso. BMJ Glob Health 2023; 8:bmjgh-2022-011316. [PMID: 37068848 PMCID: PMC10111920 DOI: 10.1136/bmjgh-2022-011316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Accepted: 03/24/2023] [Indexed: 04/19/2023] Open
Abstract
BACKGROUND The WHO recommends use of the RTS,S/AS01E (RTS,S) malaria vaccine for young children living in areas of moderate to high Plasmodium falciparum malaria transmission and suggests countries consider seasonal vaccination in areas with highly seasonal malaria. Seasonal vaccination is uncommon and may require adaptations with potential cost consequences. This study prospectively estimates cost of seasonal malaria vaccine delivery in Mali and Burkina Faso. METHODS Three scenarios for seasonal vaccine delivery are costed (1) mass campaign only, (2) routine Expanded Programme on Immunisation (EPI) and (3) mixed delivery (mass campaign and routine EPI)), from the government's perspective. Resource use data are informed by previous new vaccine introductions, supplemented with primary data from a sample of health facilities and administrative units. FINDINGS At an assumed vaccine price of US $5 per dose, the economic cost per dose administered ranges between $7.73 and $8.68 (mass campaign), $7.04 and $7.38 (routine EPI) and $7.26 and $7.93 (mixed delivery). Excluding commodities, the cost ranges between $1.17 and $2.12 (mass campaign), $0.48 and $0.82 (routine EPI) and $0.70 and $1.37 (mixed delivery). The financial non-commodity cost per dose administered ranges between $0.99 and $1.99 (mass campaign), $0.39 and $0.76 (routine EPI) and $0.58 and $1.28 (mixed delivery). Excluding commodity costs, service delivery is the main cost driver under the mass campaign scenario, accounting for 36% to 55% of the financial cost. Service delivery accounts for 2%-8% and 12%-23% of the total financial cost under routine EPI and mixed delivery scenarios, respectively. CONCLUSION Vaccine delivery using the mass campaign approach is most costly followed by mixed delivery and routine EPI delivery approaches, in both countries. Our cost estimates provide useful insights for decisions regarding delivery approaches, as countries plan the malaria vaccine rollout.
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Affiliation(s)
- Halimatou Diawara
- Malaria Research and Training Centre, University of Science Techniques and Technologies of Bamako, Bamako, Mali
| | - Fadima Yaya Bocoum
- Chercheur en sciences sociales, Institut de Recherche en Sciences de la Santé, Ouagadougou, Burkina Faso
| | - Alassane Dicko
- Malaria Research and Training Centre, University of Science Techniques and Technologies of Bamako, Bamako, Mali
| | - Ann Levin
- Levin & Morgan LLC, Bethesda, Maryland, USA
| | | | - Fatoumata Koita
- Malaria Research and Training Centre, University of Science Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Rosemonde Guissou
- Chercheur en sciences sociales, Institut de Recherche en Sciences de la Santé, Ouagadougou, Burkina Faso
| | | | - Seydou Traoré
- Malaria Research and Training Centre, University of Science Techniques and Technologies of Bamako, Bamako, Mali
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12
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Kouriba B, Arama C, Ouologuem DT, Cissoko Y, Diakite M, Beavogui AH, Wele M, Tekete M, Fofana B, Dama S, Maiga H, Kone A, Niangaly A, Diarra I, Daou M, Guindo A, Traore K, Coulibaly D, Kone AK, Dicko A, Clark TG, Doumbo OK, Djimde A. IFNγ, TNFα polymorphisms and IFNγ serum levels are associated with the clearance of drug-resistant P. falciparum in Malian children. Cytokine 2023; 164:156137. [PMID: 36773528 DOI: 10.1016/j.cyto.2023.156137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 02/11/2023]
Abstract
Host immunity has been suggested to clear drug-resistant parasites in malaria-endemic settings. However, the immunogenetic mechanisms involved in parasite clearance are poorly understood. Characterizing the host's immunity and genes involved in controlling the parasitic infection can inform the development of blood-stage malaria vaccines. This study investigates host regulatory cytokines and immunogenomic factors associated with the clearance of Plasmodium falciparum carrying a chloroquine resistance genotype. Biological samples from participants of previous drug efficacy trials conducted in two Malian localities were retrieved. The P. falciparum chloroquine resistance transporter (Pfcrt) gene was genotyped using parasite DNA. Children carrying parasites with the mutant allele (Pfcrt-76T) were classified based on their ability to clear their parasites. The levels of the different cytokines were measured in serum. The polymorphisms of specific human genes involved in malaria susceptibility were genotyped using human DNA. The prevalence of the Pfcrt-76T was significantly higher in Kolle than in Bandiagara (81.6 % vs 38.6 %, p < 10-6). The prevalence of children who cleared their mutant parasites was significantly higher in Bandiagara than in Kolle (82.2 % vs 67.4 %, p < 0.05). The genotyping of host genes revealed that IFN-γ -874 T and TNF-α -308A alleles were positively associated with parasite clearance. Cytokine profiling revealed that IFN-γ level was positively associated with parasite clearance (p = 0.04). This study highlights the role of host's immunity and immunogenetic factors to clear resistant parasites, suggesting further characterization of these polymorphisms may help to develop novel approaches to antiparasitic treatment strategies.
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Affiliation(s)
- Bourema Kouriba
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali; Centre d'Infectiologie Charles Mérieux-Mali, Mali.
| | - Charles Arama
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Dinkorma T Ouologuem
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Yacouba Cissoko
- Department of Infectious and Tropical Diseases, Point G Teaching Hospital, Bamako, Mali
| | - Mahamadou Diakite
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Abdoul Habib Beavogui
- Maferinyah National Training and Research Center in Rural Health, Forecariah, Guinea
| | - Mamadou Wele
- Institute of Applied Sciences, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Mamadou Tekete
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Bakary Fofana
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Souleymane Dama
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Hamma Maiga
- Institut National de Santé Publique, Bamako, Mali
| | - Aminatou Kone
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Amadou Niangaly
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Issa Diarra
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Modibo Daou
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Ando Guindo
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Karim Traore
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Drissa Coulibaly
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Abdoulaye K Kone
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Taane G Clark
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel St., London WC1E 7HT, UK; Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, Keppel St, London WC1E 7HT, UK
| | - Ogobara K Doumbo
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Abdoulaye Djimde
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali.
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13
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Funnell S, Jull J, Mbuagbaw L, Welch V, Dewidar O, Wang X, Lesperance M, Ghogomu E, Rizvi A, Akl EA, Avey MT, Antequera A, Bhutta ZA, Chamberlain C, Craig P, Cuervo LG, Dicko A, Ellingwood H, Feng C, Francis D, Greer-Smith R, Hardy BJ, Harwood M, Hatcher-Roberts J, Horsley T, Juando-Prats C, Kasonde M, Kennedy M, Kredo T, Krentel A, Kristjansson E, Langer L, Little J, Loder E, Magwood O, Mahande MJ, Melendez-Torres GJ, Moore A, Niba LL, Nicholls SG, Nkangu MN, Lawson DO, Obuku E, Okwen P, Pantoja T, Petkovic J, Petticrew M, Pottie K, Rader T, Ramke J, Riddle A, Shamseer L, Sharp M, Shea B, Tanuseputro P, Tugwell P, Tufte J, Von Elm E, Waddington HS, Wang H, Weeks L, Wells G, White H, Wiysonge CS, Wolfenden L, Young T. Improving social justice in observational studies: protocol for the development of a global and Indigenous STROBE-equity reporting guideline. Int J Equity Health 2023; 22:55. [PMID: 36991403 PMCID: PMC10060140 DOI: 10.1186/s12939-023-01854-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 02/27/2023] [Indexed: 03/31/2023] Open
Abstract
BACKGROUND Addressing persistent and pervasive health inequities is a global moral imperative, which has been highlighted and magnified by the societal and health impacts of the COVID-19 pandemic. Observational studies can aid our understanding of the impact of health and structural oppression based on the intersection of gender, race, ethnicity, age and other factors, as they frequently collect this data. However, the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guideline, does not provide guidance related to reporting of health equity. The goal of this project is to develop a STROBE-Equity reporting guideline extension. METHODS We assembled a diverse team across multiple domains, including gender, age, ethnicity, Indigenous background, disciplines, geographies, lived experience of health inequity and decision-making organizations. Using an inclusive, integrated knowledge translation approach, we will implement a five-phase plan which will include: (1) assessing the reporting of health equity in published observational studies, (2) seeking wide international feedback on items to improve reporting of health equity, (3) establishing consensus amongst knowledge users and researchers, (4) evaluating in partnership with Indigenous contributors the relevance to Indigenous peoples who have globally experienced the oppressive legacy of colonization, and (5) widely disseminating and seeking endorsement from relevant knowledge users. We will seek input from external collaborators using social media, mailing lists and other communication channels. DISCUSSION Achieving global imperatives such as the Sustainable Development Goals (e.g., SDG 10 Reduced inequalities, SDG 3 Good health and wellbeing) requires advancing health equity in research. The implementation of the STROBE-Equity guidelines will enable a better awareness and understanding of health inequities through better reporting. We will broadly disseminate the reporting guideline with tools to enable adoption and use by journal editors, authors, and funding agencies, using diverse strategies tailored to specific audiences.
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Affiliation(s)
- Sarah Funnell
- Department of Family Medicine, Queen's University, Kingston, Canada
- Department of Family Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Janet Jull
- School of Rehabilitation Therapy, Faculty of Health Sciences, Queen's University, Kingston, Canada
| | - Lawrence Mbuagbaw
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Canada
| | - Vivian Welch
- Bruyère Research Institute, Bruyère Continuing Care and University of Ottawa, 85 Primrose, Ottawa, Ontario, Canada.
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada.
| | - Omar Dewidar
- Bruyère Research Institute, Bruyère Continuing Care and University of Ottawa, 85 Primrose, Ottawa, Ontario, Canada
| | - Xiaoqin Wang
- Michael G. DeGroote Institute for Pain Research and Care, McMaster University, Hamilton, Canada
| | - Miranda Lesperance
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
| | - Elizabeth Ghogomu
- Bruyère Research Institute, Bruyère Continuing Care and University of Ottawa, 85 Primrose, Ottawa, Ontario, Canada
| | - Anita Rizvi
- School of Psychology, University of Ottawa, Ottawa, Canada
| | - Elie A Akl
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Canada
- Department of Internal Medicine, American University of Beirut, Beirut, Lebanon
| | - Marc T Avey
- Canadian Council on Animal Care, Ottawa, Canada
| | - Alba Antequera
- International Health Department, ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Zulfiqar A Bhutta
- Centre for Global Child Health, Hospital for Sick Children, Toronto, Canada
- Institute for Global Health & Development, The Aga Khan University, Karachi, Pakistan
| | - Catherine Chamberlain
- Indigenous Health Equity Unit, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
- Judith Lumley Centre, School of Nursing and Midwifery, La Trobe University, Melbourne, Australia
| | - Peter Craig
- MRC/CSO Social and Public Health Sciences Unit, School of Health and Wellbeing, University of Glasgow, Glasgow, UK
| | - Luis Gabriel Cuervo
- Unit of Health Services and Access, Department of Health Systems and Services, Pan American Health Organization (PAHO/WHO), Washington, DC, USA
- Doctoral School, Department of Paediatrics, Obstetrics & Gynaecology, and Preventive Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Alassane Dicko
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Holly Ellingwood
- Department of Psychology, Department of Law, Carleton University, Ottawa, ON, Canada
| | - Cindy Feng
- Department of Community Health and Epidemiology, Dalhousie University, Halifax, Canada
| | - Damian Francis
- School of Health and Human Performance, Georgia College, Milledgville, USA
| | - Regina Greer-Smith
- Healthcare Research Associates, LLC/S.T.A.R. Initiative, Los Angeles, USA
| | - Billie-Jo Hardy
- Well Living House, Li Ka Shing Knowledge Institute, University of Toronto, Toronto, Ontario, Canada
- Waakebiness Institute for Indigenous Health, Dalla Lana School of Public Health, University of Toronto, Toronto, Canada
| | - Matire Harwood
- General Practice and Primary Healthcare, University of Auckland, Auckland, New Zealand
| | - Janet Hatcher-Roberts
- WHO Collaborating Centre for Knowledge Translation and Health Technology Assessment in Health Equity, Ottawa, Canada
| | - Tanya Horsley
- Royal College of Physicians and Surgeons of Canada, Ottawa, Canada
| | - Clara Juando-Prats
- Applied Health Research Center, St. Michael's Hospital, Toronto, Canada
- Dalla School of Public Health, University of Toronto, Toronto, Canada
| | | | - Michelle Kennedy
- School of Medicine and Public Health, The University of Newcastle, Callaghan, New South Wales, Australia
| | - Tamara Kredo
- Centre for Evidence Based Health Care, Department of Global Health, Stellenbosch University, Stellenbosch, South Africa
- Cochrane South Africa, South African Medical Research Council, Cape Town, South Africa
| | - Alison Krentel
- Bruyère Research Institute, Bruyère Continuing Care and University of Ottawa, 85 Primrose, Ottawa, Ontario, Canada
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
| | - Elizabeth Kristjansson
- Interdisciplinary School of Health Sciences, Faculty of Health Sciences, University of Ottawa, Ottawa, Canada
| | - Laurenz Langer
- Africa Centre for Evidence, University of Johannesburg, Johannesburg, South Africa
| | - Julian Little
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
| | | | - Olivia Magwood
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
- Interdisciplinary School of Health Sciences, Faculty of Health Sciences, University of Ottawa, Ottawa, Canada
| | - Michael Johnson Mahande
- Department of Epidemiology & Biostatistics, Institute of Public Health, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | | | - Ainsley Moore
- Department of Family Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Loveline Lum Niba
- Department of Public Health, Faculty of Health Sciences, The University of Bamenda, Bamenda, Cameroon
| | - Stuart G Nicholls
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | | | - Daeria O Lawson
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Canada
| | - Ekwaro Obuku
- College of Health Sciences, Makerere University College of Health Sciences, Kampala, Uganda
| | - Patrick Okwen
- Department of Public Health, Faculty of Health Sciences, The University of Bamenda, Bamenda, Cameroon
| | - Tomas Pantoja
- Department of Family Medicine, School of Medicine, Pontifica Universidad Católica de Chile, Santiago, Chile
| | - Jennifer Petkovic
- Bruyère Research Institute, Bruyère Continuing Care and University of Ottawa, 85 Primrose, Ottawa, Ontario, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Mark Petticrew
- Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine, London, UK
| | - Kevin Pottie
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
- Department of Family Medicine, Epidemiology and Biostatistics, Western University, London, Ontario, Canada
| | - Tamara Rader
- Freelance Health Research Librarian, Ottawa, Canada
| | - Jacqueline Ramke
- International Centre for Eye Health, London School of Hygiene & Tropical Medicine, London, UK
- School of Optometry and Vision Science, University of Auckland, Auckland, New Zealand
| | - Alison Riddle
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
| | - Larissa Shamseer
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Melissa Sharp
- Health Research Board Centre for Primary Care Research, Department of General Practice, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Bev Shea
- Department of Family Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Peter Tanuseputro
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Peter Tugwell
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
- Department of Medicine , University of Ottawa, Ottawa, Ontario, Canada
| | | | - Erik Von Elm
- Cochrane Switzerland, Centre for Primary Care and Public Health (Unisanté), University of Lausanne, Lausanne, Switzerland
| | - Hugh Sharma Waddington
- London International Development Centre, London School of Hygiene & Tropical Medicine, London, UK
| | - Harry Wang
- Bruyère Research Institute, Bruyère Continuing Care and University of Ottawa, 85 Primrose, Ottawa, Ontario, Canada
- Department of Medicine , University of Ottawa, Ottawa, Ontario, Canada
| | - Laura Weeks
- Canadian Agency for Drugs and Technologies in Health, Ottawa, Ontario, Canada
| | - George Wells
- Department of Family Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Canada
- University of Ottawa Heart Institute, Ottawa, Canada
| | | | - Charles Shey Wiysonge
- Centre for Evidence Based Health Care, Department of Global Health, Stellenbosch University, Stellenbosch, South Africa
- Cochrane South Africa, South African Medical Research Council, Cape Town, South Africa
- HIV and other Infectious Diseases Research Unit, Durban, South Africa
| | - Luke Wolfenden
- Cochrane South Africa, South African Medical Research Council, Cape Town, South Africa
| | - Taryn Young
- Centre for Evidence Based Health Care, Department of Global Health, Stellenbosch University, Stellenbosch, South Africa
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14
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Beshir KB, Muwanguzi J, Nader J, Mansukhani R, Traore A, Gamougam K, Ceesay S, Bazie T, Kolie F, Lamine MM, Cairns M, Snell P, Scott S, Diallo A, Merle CS, NDiaye JL, Razafindralambo L, Moroso D, Ouedraogo JB, Zongo I, Kessely H, Doumagoum D, Bojang K, Ceesay S, Loua K, Maiga H, Dicko A, Sagara I, Laminou IM, Ogboi SJ, Eloike T, Milligan P, Sutherland CJ. Prevalence of Plasmodium falciparum haplotypes associated with resistance to sulfadoxine-pyrimethamine and amodiaquine before and after upscaling of seasonal malaria chemoprevention in seven African countries: a genomic surveillance study. Lancet Infect Dis 2023; 23:361-370. [PMID: 36328000 DOI: 10.1016/s1473-3099(22)00593-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 08/08/2022] [Accepted: 09/02/2022] [Indexed: 12/26/2022]
Abstract
BACKGROUND Seasonal malaria chemoprevention is used in 13 countries in the Sahel region of Africa to prevent malaria in children younger than 5 years. Resistance of Plasmodium falciparum to seasonal malaria chemoprevention drugs across the region is a potential threat to this intervention. METHODS Between December, 2015, and March, 2016, and between December, 2017, and March, 2018, immediately following the 2015 and 2017 malaria transmission seasons, community surveys were done among children younger than 5 years and individuals aged 10-30 years in districts implementing seasonal malaria chemoprevention with sulfadoxine-pyrimethamine and amodiaquine in Burkina Faso, Chad, Guinea, Mali, Nigeria, Niger and The Gambia. Dried blood samples were collected and tested for P falciparum DNA by PCR. Resistance-associated haplotypes of the P falciparum genes crt, mdr1, dhfr, and dhps were identified by quantitative PCR and sequencing of isolates from the collected samples, and survey-weighted prevalence and prevalence ratio between the first and second surveys were estimated for each variant. FINDINGS 5130 (17·5%) of 29 274 samples from 2016 and 2176 (7·6%) of 28 546 samples from 2018 were positive for P falciparum on quantitative PCR. Among children younger than 5 years, parasite carriage decreased from 2844 of 14 345 samples (19·8% [95% CI 19·2-20·5]) in 2016 to 801 of 14 019 samples (5·7% [5·3-6·1]) in 2018 (prevalence ratio 0·27 [95% CI 0·24-0·31], p<0·0001). Genotyping found no consistent evidence of increasing prevalence of amodiaquine resistance-associated variants of crt and mdr1 between 2016 and 2018. The dhfr haplotype IRN (consisting of 51Ile-59Arg-108Asn) was common at both survey timepoints, but the dhps haplotype ISGEAA (431Ile-436Ser-437Gly-540Glu-581Ala-613Ala), crucial for resistance to sulfadoxine-pyrimethamine, was always rare. Parasites carrying amodiaquine resistance-associated variants of both crt and mdr1 together with dhfr IRN and dhps ISGEAA occurred in 0·05% of isolates. The emerging dhps haplotype VAGKGS (431Val-436Ala-437Gly-540Lys-581Gly-613Ser) was present in four countries. INTERPRETATION In seven African countries, evidence of a significant reduction in parasite carriage among children receiving seasonal malaria chemoprevention was found 2 years after intervention scale-up. Combined resistance-associated haplotypes remained rare, and seasonal malaria chemoprevention with sulfadoxine-pyrimethamine and amodiaquine is expected to retain effectiveness. The threat of future erosion of effectiveness due to dhps variant haplotypes requires further monitoring. FUNDING Unitaid.
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Affiliation(s)
- Khalid B Beshir
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Julian Muwanguzi
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Johanna Nader
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK; Department of Genetics and Bioinformatics, Division of Health Data and Digitalization, Norwegian Institute of Public Health, Oslo, Norway
| | - Raoul Mansukhani
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Aliou Traore
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | | | - Sainey Ceesay
- Medical Research Council Laboratories, London School of Hygiene & Tropical Medicine, Fajara, The Gambia
| | - Thomas Bazie
- Institute of Health Science Research, Bobo-Dioulasso, Burkina Faso
| | - Fassou Kolie
- Université Gamal Abdel Nasser de Conakry, Conakry, Guinea
| | | | - Matt Cairns
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Paul Snell
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Susana Scott
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK
| | | | - Corinne S Merle
- Special Programme for Research & Training in Tropical Diseases, WHO, Geneva, Switzerland
| | | | | | - Diego Moroso
- Malaria Consortium, Kampala, Uganda; UK Foreign, Commonwealth, & Development Office, Lagos, Nigeria
| | | | - Issaka Zongo
- Institute of Health Science Research, Bobo-Dioulasso, Burkina Faso
| | - Hamit Kessely
- Centre de Support en Santé Internationale, N'Djamena, Chad
| | | | - Kalifa Bojang
- Medical Research Council Laboratories, London School of Hygiene & Tropical Medicine, Fajara, The Gambia
| | - Serign Ceesay
- Medical Research Council Laboratories, London School of Hygiene & Tropical Medicine, Fajara, The Gambia
| | - Kovana Loua
- Université Gamal Abdel Nasser de Conakry, Conakry, Guinea
| | - Hamma Maiga
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | - Issaka Sagara
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | | | | | - Tony Eloike
- Jedima International Health Consult, Lagos, Nigeria
| | - Paul Milligan
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Colin J Sutherland
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
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15
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Gonçalves BP, Pérez-Caballero R, Barry A, Gaoussou S, Lewin A, Issiaka D, Keita S, Diarra BS, Mahamar A, Attaher O, Narum DL, Kurtis JD, Dicko A, Duffy PE, Fried M. Natural History of Malaria Infections During Early Childhood in Twins. J Infect Dis 2023; 227:171-178. [PMID: 35849702 DOI: 10.1093/infdis/jiac294] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 06/06/2022] [Accepted: 07/15/2022] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND The frequency and clinical presentation of malaria infections show marked heterogeneity in epidemiological studies. However, deeper understanding of this variability is hampered by the difficulty in quantifying all relevant factors. Here, we report the history of malaria infections in twins, who are exposed to the same in utero milieu, share genetic factors, and are similarly exposed to vectors. METHODS Data were obtained from a Malian longitudinal birth cohort. Samples from 25 twin pairs were examined for malaria infection and antibody responses. Bayesian models were developed for the number of infections during follow-up. RESULTS In 16 of 25 pairs, both children were infected and often developed symptoms. In 8 of 25 pairs, only 1 twin was infected, but usually only once or twice. Statistical models suggest that this pattern is not inconsistent with twin siblings having the same underlying infection rate. In a pair with discordant hemoglobin genotype, parasite densities were consistently lower in the child with hemoglobin AS, but antibody levels were similar. CONCLUSIONS By using a novel design, we describe residual variation in malaria phenotypes in naturally matched children and confirm the important role of environmental factors, as suggested by the between-twin pair heterogeneity in malaria history.
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Affiliation(s)
- Bronner P Gonçalves
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Raúl Pérez-Caballero
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Amadou Barry
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Santara Gaoussou
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Alexandra Lewin
- Department of Medical Statistics, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Djibrilla Issiaka
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekouba Keita
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Bacary S Diarra
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Almahamoudou Mahamar
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Oumar Attaher
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - David L Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jonathan D Kurtis
- Center for International Health Research, Rhode Island Hospital, and Department of Pathology and Laboratory Medicine, Brown University Medical School, Providence, Rhode Island, USA
| | - Alassane Dicko
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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Richie TL, Church LWP, Murshedkar T, Billingsley PF, James ER, Chen MC, Abebe Y, KC N, Chakravarty S, Dolberg D, Healy SA, Diawara H, Sissoko MS, Sagara I, Cook DM, Epstein JE, Mordmüller B, Kapulu M, Kreidenweiss A, Franke-Fayard B, Agnandji ST, López Mikue MSA, McCall MBB, Steinhardt L, Oneko M, Olotu A, Vaughan AM, Kublin JG, Murphy SC, Jongo S, Tanner M, Sirima SB, Laurens MB, Daubenberger C, Silva JC, Lyke KE, Janse CJ, Roestenberg M, Sauerwein RW, Abdulla S, Dicko A, Kappe SHI, Lee Sim BK, Duffy PE, Kremsner PG, Hoffman SL. Sporozoite immunization: innovative translational science to support the fight against malaria. Expert Rev Vaccines 2023; 22:964-1007. [PMID: 37571809 PMCID: PMC10949369 DOI: 10.1080/14760584.2023.2245890] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 08/04/2023] [Indexed: 08/13/2023]
Abstract
INTRODUCTION Malaria, a devastating febrile illness caused by protozoan parasites, sickened 247,000,000 people in 2021 and killed 619,000, mostly children and pregnant women in sub-Saharan Africa. A highly effective vaccine is urgently needed, especially for Plasmodium falciparum (Pf), the deadliest human malaria parasite. AREAS COVERED Sporozoites (SPZ), the parasite stage transmitted by Anopheles mosquitoes to humans, are the only vaccine immunogen achieving >90% efficacy against Pf infection. This review describes >30 clinical trials of PfSPZ vaccines in the U.S.A., Europe, Africa, and Asia, based on first-hand knowledge of the trials and PubMed searches of 'sporozoites,' 'malaria,' and 'vaccines.' EXPERT OPINION First generation (radiation-attenuated) PfSPZ vaccines are safe, well tolerated, 80-100% efficacious against homologous controlled human malaria infection (CHMI) and provide 18-19 months protection without boosting in Africa. Second generation chemo-attenuated PfSPZ are more potent, 100% efficacious against stringent heterologous (variant strain) CHMI, but require a co-administered drug, raising safety concerns. Third generation, late liver stage-arresting, replication competent (LARC), genetically-attenuated PfSPZ are expected to be both safe and highly efficacious. Overall, PfSPZ vaccines meet safety, tolerability, and efficacy requirements for protecting pregnant women and travelers exposed to Pf in Africa, with licensure for these populations possible within 5 years. Protecting children and mass vaccination programs to block transmission and eliminate malaria are long-term objectives.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Sara A. Healy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Halimatou Diawara
- Malaria Research and Training Center, Mali-NIAID ICER, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Mahamadou S. Sissoko
- Malaria Research and Training Center, Mali-NIAID ICER, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Issaka Sagara
- Malaria Research and Training Center, Mali-NIAID ICER, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - David M. Cook
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Judith E. Epstein
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Benjamin Mordmüller
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
- Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany
| | - Melissa Kapulu
- Biosciences Department, Kenya Medical Research Institute KEMRI-Wellcome Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Andrea Kreidenweiss
- Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany
| | | | - Selidji T. Agnandji
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | | | - Matthew B. B. McCall
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
- Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
| | - Laura Steinhardt
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Martina Oneko
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | - Ally Olotu
- Bagamoyo Research and Training Center, Ifakara Health Institute, Bagamoyo, Tanzania
| | - Ashley M. Vaughan
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA, USA
- Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - James G. Kublin
- Department of Global Health, University of Washington, Seattle, WA, USA
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Sean C. Murphy
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
- Center for Emerging and Re-emerging Infectious Diseases and Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Said Jongo
- Bagamoyo Research and Training Center, Ifakara Health Institute, Bagamoyo, Tanzania
| | - Marcel Tanner
- Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | - Matthew B. Laurens
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Claudia Daubenberger
- Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Joana C. Silva
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Kirsten E. Lyke
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Chris J. Janse
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Meta Roestenberg
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Robert W. Sauerwein
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Salim Abdulla
- Bagamoyo Research and Training Center, Ifakara Health Institute, Bagamoyo, Tanzania
| | - Alassane Dicko
- Malaria Research and Training Center, Mali-NIAID ICER, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Stefan H. I. Kappe
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA, USA
- Department of Pediatrics, University of Washington, Seattle, WA, USA
| | | | - Patrick E. Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Peter G. Kremsner
- Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany
- German Center for Infection Research (DZIF), partner site Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
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Gaoussou S, Attaher O, Swihart B, Traore M, Diarra S, Soumbounou IH, Ndiaye O, Issiaka D, Morrison R, Mahamar A, Duffy PE, Dicko A, Fried M. Pregnancy outcomes in a malaria-exposed Malian cohort of women of child-bearing age. Front Med (Lausanne) 2022; 9:1061538. [PMID: 36569122 PMCID: PMC9772013 DOI: 10.3389/fmed.2022.1061538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 11/24/2022] [Indexed: 12/12/2022] Open
Abstract
In Sub-Saharan Africa, malaria continues to be associated with adverse pregnancy outcomes including stillbirth, early neonatal death, preterm delivery, and low birth weight. Current preventive measures are insufficient and new interventions are urgently needed. However, before such interventions can be tested in pregnant women, background information on pregnancy outcomes in this target population must be collected. We conducted an observational study in Ouélessébougou, Mali, a malaria-endemic area where first antenatal visit commonly occurs during the second trimester of pregnancy, hindering calculation of miscarriage rate in the population. To accurately determine the rate of miscarriage, 799 non-pregnant women of child-bearing age were enrolled and surveyed via monthly follow up visits that included pregnancy tests. Out of 505 women that completed the study, 364 became pregnant and 358 pregnancies were analyzed: 43 (12%) resulted in miscarriage, 28 (65.1%) occurred during the first trimester of pregnancy. We also determined rates of stillbirth, neonatal death, preterm delivery, and small for gestational age. The results showed high rate of miscarriage during the first trimester and established a basis to evaluate new interventions to prevent pregnancy malaria. This survey design enabled identification of first trimester miscarriages that are often missed by studies conducted in antenatal clinics. Clinical trial registration [https://clinicaltrials.gov/], identifier [NCT0297 4608].
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Affiliation(s)
- Santara Gaoussou
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Oumar Attaher
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Bruce Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Moussa Traore
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Soumaila Diarra
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Ibrahim H. Soumbounou
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Oulematou Ndiaye
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Djibrilla Issiaka
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Robert Morrison
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Almahamoudou Mahamar
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Patrick E. Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Alassane Dicko
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States,*Correspondence: Michal Fried,
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18
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Oulton T, Mahamar A, Sanogo K, Diallo M, Youssouf A, Niambele SM, Samaké S, Keita S, Sinaba Y, Sacko A, Traore SF, Lanke K, Collins KA, Bradley J, Drakeley C, Stone WJR, Dicko A. Persistence of Plasmodium falciparum HRP-2 antigenaemia after artemisinin combination therapy is not associated with gametocytes. Malar J 2022; 21:372. [PMID: 36474274 PMCID: PMC9724264 DOI: 10.1186/s12936-022-04387-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 11/16/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND In some settings, sensitive field diagnostic tools may be needed to achieve elimination of falciparum malaria. To this end, rapid diagnostic tests (RDTs) based on the detection of the Plasmodium falciparum protein HRP-2 are being developed with increasingly lower limits of detection. However, it is currently unclear how parasite stages that are unaffected by standard drug treatments may contribute to HRP-2 detectability and potentially confound RDT results even after clearance of blood stage infection. This study assessed the detectability of HRP-2 in periods of post-treatment residual gametocytaemia. METHODS A cohort of 100 P. falciparum infected, gametocyte positive individuals were treated with or without the gametocytocidal drug primaquine (PQ), alongside standard artemisinin-based combination therapy (ACT), in the context of a randomised clinical trial in Ouelessebougou, Mali. A quantitative ELISA was used to measure levels of HRP-2, and compared time to test negativity using a standard and ultra-sensitive RDT (uRDT) between residual gametocyte positive and negative groups. RESULTS Time to test negativity was longest by uRDT, followed by ELISA and then standard RDT. No significant difference in time to negativity was found between the treatment groups with and without residual gametocytes: uRDT (HR 0.79 [95% CI 0.52-1.21], p = 0.28), RDT (HR 0.77 [95% CI 0.51-1.15], p = 0.20) or ELISA (HR 0.88 [95% CI 0.59-1.32], p = 0.53). Similarly, no difference was observed when adjusting for baseline asexual parasite density. Quantified levels of HRP-2 over time were similar between groups, with differences attributable to asexual parasite densities. Furthermore, no difference in levels of HRP-2 was found between individuals who were or were not infectious to mosquitoes (OR 1.19 [95% CI 0.98-1.46], p = 0.077). CONCLUSIONS Surviving sexual stage parasites after standard ACT treatment do not contribute to the persistence of HRP-2 antigenaemia, and appear to have little impact on RDT results.
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Affiliation(s)
- Tate Oulton
- grid.8991.90000 0004 0425 469XDepartment of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Almahamoudou Mahamar
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Koualy Sanogo
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Makonon Diallo
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Ahamadou Youssouf
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sidi M. Niambele
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Siaka Samaké
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekouba Keita
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Youssouf Sinaba
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Adama Sacko
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekou F. Traore
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Kjerstin Lanke
- grid.10417.330000 0004 0444 9382Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, The Netherlands
| | - Katharine A. Collins
- grid.10417.330000 0004 0444 9382Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, The Netherlands
| | - John Bradley
- grid.8991.90000 0004 0425 469XMRC International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
| | - Chris Drakeley
- grid.8991.90000 0004 0425 469XDepartment of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Will J. R. Stone
- grid.8991.90000 0004 0425 469XDepartment of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Alassane Dicko
- grid.461088.30000 0004 0567 336XMalaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
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Thompson HA, Hogan AB, Walker PGT, Winskill P, Zongo I, Sagara I, Tinto H, Ouedraogo JB, Dicko A, Chandramohan D, Greenwood B, Cairns M, Ghani AC. Seasonal use case for the RTS,S/AS01 malaria vaccine: a mathematical modelling study. Lancet Glob Health 2022; 10:e1782-e1792. [PMID: 36400084 DOI: 10.1016/s2214-109x(22)00416-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 08/03/2022] [Accepted: 09/15/2022] [Indexed: 11/17/2022]
Abstract
BACKGROUND A 2021 clinical trial of seasonal RTS,S/AS01E (RTS,S) vaccination showed that vaccination was non-inferior to seasonal malaria chemoprevention (SMC) in preventing clinical malaria. The combination of these two interventions provided significant additional protection against clinical and severe malaria outcomes. Projections of the effect of this novel approach to RTS,S vaccination in seasonal transmission settings for extended timeframes and across a range of epidemiological settings are needed to inform policy recommendations. METHODS We used a mathematical, individual-based model of malaria transmission that was fitted to data on the relationship between entomological inoculation rate and parasite prevalence, clinical disease, severe disease, and deaths from multiple sites across Africa. The model was validated with results from a phase 3b trial assessing the effect of SV-RTS,S in Mali and Burkina Faso. We developed three intervention efficacy models with varying degrees and durations of protection for our population-level modelling analysis to assess the potential effect of an RTS,S vaccination schedule based on age (doses were delivered to children aged 6 months, 7·5 months, and 9 months for the first three doses, and at 27 months of age for the fourth dose) or season (children aged 5-17 months at the time of first vaccination received the first three doses in the 3 months preceding the transmission season, with any subsequent doses up to five doses delivered annually) in seasonal transmission settings both in the absence and presence of SMC with sulfadoxine-pyrimethamine plus amodiaquine. This is modelled as a full therapeutic course delivered every month for four or five months of the peak in transmission season. Estimates of cases and deaths averted in a population of 100 000 children aged 0-5 years were calculated over a 15-year time period for a range of levels of malaria transmission intensity (Plasmodium falciparum parasite prevalence in children aged 2-10 years between 10% and 65%) and over two west Africa seasonality archetypes. FINDINGS Seasonally targeting RTS,S resulted in greater absolute reductions in malaria cases and deaths compared with an age-based strategy, averting an additional 14 000-47 000 cases per 100 000 children aged 5 years and younger over 15 years, dependent on seasonality and transmission intensity. We predicted that adding seasonally targeted RTS,S to SMC would reduce clinical incidence by up to an additional 42 000-67 000 cases per 100 000 children aged 5 years and younger over 15 years compared with SMC alone. Transmission season duration was a key determinant of intervention effect, with the advantage of adding RTS,S to SMC predicted to be smaller with shorter transmission seasons. INTERPRETATION RTS,S vaccination in seasonal settings could be a valuable additional tool to existing interventions, with seasonal delivery maximising the effect relative to an age-based approach. Decisions surrounding deployment strategies of RTS,S in such settings will need to consider the local and regional variations in seasonality, current rates of other interventions, and potential achievable RTS,S coverage. FUNDING UK Medical Research Council, UK Foreign Commonwealth & Development Office, The Wellcome Trust, and The Royal society.
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Affiliation(s)
- Hayley A Thompson
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London UK
| | - Alexandra B Hogan
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London UK; School of Population Health, University of New South Wales, Sydney, NSW, Australia
| | - Patrick G T Walker
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London UK
| | - Peter Winskill
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London UK
| | - Issaka Zongo
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Issaka Sagara
- Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali
| | - Halidou Tinto
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso; Institut National de Santé Publique - Centre Muraz, Bobo-Dioulasso, Burkina Faso
| | - Jean-Bosco Ouedraogo
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso; Institut Sciences et Techniques, Bobo-Dioulasso, Burkina Faso
| | - Alassane Dicko
- Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali
| | - Daniel Chandramohan
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Brian Greenwood
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Matt Cairns
- International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
| | - Azra C Ghani
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London UK.
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20
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Cairns M, Barry A, Zongo I, Sagara I, Yerbanga SR, Diarra M, Zoungrana C, Issiaka D, Sienou AA, Tapily A, Sanogo K, Kaya M, Traore S, Diarra K, Yalcouye H, Sidibe Y, Haro A, Thera I, Snell P, Grant J, Tinto H, Milligan P, Chandramohan D, Greenwood B, Dicko A, Ouedraogo JB. The duration of protection against clinical malaria provided by the combination of seasonal RTS,S/AS01 E vaccination and seasonal malaria chemoprevention versus either intervention given alone. BMC Med 2022; 20:352. [PMID: 36203149 PMCID: PMC9540742 DOI: 10.1186/s12916-022-02536-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 08/18/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A recent trial of 5920 children in Burkina Faso and Mali showed that the combination of seasonal vaccination with the RTS,S/AS01E malaria vaccine (primary series and two seasonal boosters) and seasonal malaria chemoprevention (four monthly cycles per year) was markedly more effective than either intervention given alone in preventing clinical malaria, severe malaria, and deaths from malaria. METHODS In order to help optimise the timing of these two interventions, trial data were reanalysed to estimate the duration of protection against clinical malaria provided by RTS,S/AS01E when deployed seasonally, by comparing the group who received the combination of SMC and RTS,S/AS01E with the group who received SMC alone. The duration of protection from SMC was also estimated comparing the combined intervention group with the group who received RTS,S/AS01E alone. Three methods were used: Piecewise Cox regression, Flexible parametric survival models and Smoothed Schoenfeld residuals from Cox models, stratifying on the study area and using robust standard errors to control for within-child clustering of multiple episodes. RESULTS The overall protective efficacy from RTS,S/AS01E over 6 months was at least 60% following the primary series and the two seasonal booster doses and remained at a high level over the full malaria transmission season. Beyond 6 months, protective efficacy appeared to wane more rapidly, but the uncertainty around the estimates increases due to the lower number of cases during this period (coinciding with the onset of the dry season). Protection from SMC exceeded 90% in the first 2-3 weeks post-administration after several cycles, but was not 100%, even immediately post-administration. Efficacy begins to decline from approximately day 21 and then declines more sharply after day 28, indicating the importance of preserving the delivery interval for SMC cycles at a maximum of four weeks. CONCLUSIONS The efficacy of both interventions was highest immediately post-administration. Understanding differences between these interventions in their peak efficacy and how rapidly efficacy declines over time will help to optimise the scheduling of SMC, malaria vaccination and the combination in areas of seasonal transmission with differing epidemiology, and using different vaccine delivery systems. TRIAL REGISTRATION The RTS,S-SMC trial in which these data were collected was registered at clinicaltrials.gov: NCT03143218.
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Affiliation(s)
- Matthew Cairns
- International Statistics and Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.
| | - Amadou Barry
- Malaria Research and Training Centre, Bamako, Mali
| | - Issaka Zongo
- Institut de Recherche en Sciences de la Santé, Bobo Dioulasso, Burkina Faso
| | | | - Serge R Yerbanga
- Institut de Recherche en Sciences de la Santé, Bobo Dioulasso, Burkina Faso
| | | | - Charles Zoungrana
- Institut de Recherche en Sciences de la Santé, Bobo Dioulasso, Burkina Faso
| | | | - Abdoul Aziz Sienou
- Institut de Recherche en Sciences de la Santé, Bobo Dioulasso, Burkina Faso
| | | | | | | | | | | | | | | | - Alassane Haro
- Institut de Recherche en Sciences de la Santé, Bobo Dioulasso, Burkina Faso
| | | | - Paul Snell
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK
| | - Jane Grant
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Halidou Tinto
- Institut de Recherche en Sciences de la Santé, Bobo Dioulasso, Burkina Faso
| | - Paul Milligan
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK
| | - Daniel Chandramohan
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Brian Greenwood
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
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21
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Sagara I, Zongo I, Cairns M, Yerbanga RS, Mahamar A, Nikièma F, Tapily A, Sompougdou F, Diarra M, Zoungrana C, Issiaka D, Haro A, Sanogo K, Aziz Sienou A, Kaya M, Traore S, Thera I, Diarra K, Dolo A, Kuepfer I, Snell P, Milligan P, Ockenhouse C, Ofori-Anyinam O, Tinto H, Djimde A, Ouedraogo JB, Dicko A, Chandramohan D, Greenwood B. The Anti-Circumsporozoite Antibody Response of Children to Seasonal Vaccination With the RTS,S/AS01E Malaria Vaccine. Clin Infect Dis 2022; 75:613-622. [PMID: 34894221 PMCID: PMC9464075 DOI: 10.1093/cid/ciab1017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND A trial in African children showed that combining seasonal vaccination with the RTS,S/AS01E vaccine with seasonal malaria chemoprevention reduced the incidence of uncomplicated and severe malaria compared with either intervention given alone. Here, we report on the anti-circumsporozoite antibody response to seasonal RTS,S/AS01E vaccination in children in this trial. METHODS Sera from a randomly selected subset of children collected before and 1 month after 3 priming doses of RTS,S/AS01E and before and 1 month after 2 seasonal booster doses were tested for anti-circumsporozoite antibodies using enzyme-linked immunosorbent assay. The association between post-vaccination antibody titer and incidence of malaria was explored. RESULTS A strong anti-circumsporozoite antibody response to 3 priming doses of RTS,S/AS01E was seen (geometric mean titer, 368.9 enzyme-linked immunosorbent assay units/mL), but titers fell prior to the first booster dose. A strong antibody response to an annual, pre-malaria transmission season booster dose was observed, but this was lower than after the primary vaccination series and lower after the second than after the first booster dose (ratio of geometric mean rise, 0.66; 95% confidence interval [CI], .57-.77). Children whose antibody response was in the upper tercile post-vaccination had a lower incidence of malaria during the following year than children in the lowest tercile (hazard ratio, 0.43; 95% CI, .28-.66). CONCLUSIONS Seasonal vaccination with RTS,S/AS01E induced a strong booster antibody response that was lower after the second than after the first booster dose. The diminished antibody response to the second booster dose was not associated with diminished efficacy. CLINICAL TRIALS REGISTRATION NCT03143218.
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Affiliation(s)
| | | | - Matthew Cairns
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - Almahamoudou Mahamar
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Frédéric Nikièma
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Amadou Tapily
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | | | - Modibo Diarra
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Charles Zoungrana
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Djibrilla Issiaka
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Alassane Haro
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Koualy Sanogo
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Abdoul Aziz Sienou
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Mahamadou Kaya
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Seydou Traore
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Ismaila Thera
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Kalifa Diarra
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Amagana Dolo
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | - Irene Kuepfer
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Paul Snell
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Paul Milligan
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | - Halidou Tinto
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Abdoulaye Djimde
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | | | - Alassane Dicko
- The Malaria Research and Training Center, University of Sciences, Techniques and Technologies, Bamako, Mali
| | | | - Brian Greenwood
- Correspondence: B. Greenwood, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel St., London WC1E 7HT, UK ()
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Sharma A, Jenkins B, Akue A, Lambert LE, Orr-Gonzalez S, Thomas ML, Mahamar A, Diarra BS, Dicko A, Fried M, Duffy PE. Plasmodium falciparum in Aotus nancymaae: A New Model for Placental Malaria. J Infect Dis 2022; 226:521-527. [PMID: 35290467 PMCID: PMC9417121 DOI: 10.1093/infdis/jiac096] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/11/2022] [Indexed: 11/08/2023] Open
Abstract
Plasmodium falciparum-infected erythrocytes that display the variant surface antigen VAR2CSA bind chondroitin sulfate A (CSA) to sequester in placental intervillous spaces, causing severe sequelae for mother and offspring. Here, we establish a placental malaria (PM) monkey model. Pregnant Aotus infected with CSA-binding P. falciparum CS2 parasites during the third trimester developed pronounced sequestration of late-stage parasites in placental intervillous spaces that express VAR2CSA and bind specifically to CSA. Similar to immune multigravid women, a monkey infected with P. falciparum CS2 parasites over successive pregnancies acquired antibodies against VAR2CSA, with potent functional activity that was boosted upon subsequent pregnancy infections. Aotus also developed functional antibodies after multiple acute PM episodes and subsequent VAR2CSA immunization. In summary, P. falciparum infections in pregnant Aotus monkeys recapitulate all the prominent features of human PM infection and immunity, and this model can be useful for basic mechanistic studies and preclinical studies to qualify candidate PM vaccines. Clinical Trials Registration: NCT02471378.
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Affiliation(s)
- Ankur Sharma
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Bethany Jenkins
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Adovi Akue
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Lynn E Lambert
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Sachy Orr-Gonzalez
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Marvin L Thomas
- Division of Veterinary Resources, Office of Research Services, National Institutes of Health, Bethesda, Maryland, USA
| | - Almahamoudou Mahamar
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Bacary S Diarra
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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23
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Woodford J, Sagara I, Diawara H, Assadou MH, Katile A, Attaher O, Issiaka D, Santara G, Soumbounou IH, Traore S, Traore M, Dicko OM, Niambele SM, Mahamar A, Kamate B, Haidara B, Sissoko K, Sankare S, Diarra SDK, Zeguime A, Doritchamou JYA, Zaidi I, Dicko A, Duffy PE. Recent malaria does not substantially impact COVID-19 antibody response or rates of symptomatic illness in communities with high malaria and COVID-19 transmission in Mali, West Africa. Front Immunol 2022; 13:959697. [PMID: 35990648 PMCID: PMC9382593 DOI: 10.3389/fimmu.2022.959697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 06/29/2022] [Indexed: 11/13/2022] Open
Abstract
Malaria has been hypothesized as a factor that may have reduced the severity of the COVID-19 pandemic in sub-Saharan Africa. To evaluate the effect of recent malaria on COVID-19 we assessed a subgroup of individuals participating in a longitudinal cohort COVID-19 serosurvey that were also undergoing intensive malaria monitoring as part of antimalarial vaccine trials during the 2020 transmission season in Mali. These communities experienced a high incidence of primarily asymptomatic or mild COVID-19 during 2020 and 2021. In 1314 individuals, 711 were parasitemic during the 2020 malaria transmission season; 442 were symptomatic with clinical malaria and 269 had asymptomatic infection. Presence of parasitemia was not associated with new COVID-19 seroconversion (29.7% (211/711) vs. 30.0% (181/603), p=0.9038) or with rates of reported symptomatic seroconversion during the malaria transmission season. In the subsequent dry season, prior parasitemia was not associated with new COVID-19 seroconversion (30.2% (133/441) vs. 31.2% (108/346), p=0.7499), with symptomatic seroconversion, or with reversion from seropositive to seronegative (prior parasitemia: 36.2% (64/177) vs. no parasitemia: 30.1% (37/119), p=0.3842). After excluding participants with asymptomatic infection, clinical malaria was also not associated with COVID-19 serostatus or symptomatic seroconversion when compared to participants with no parasitemia during the monitoring period. In communities with intense seasonal malaria and a high incidence of asymptomatic or mild COVID-19, we did not demonstrate a relationship between recent malaria and subsequent response to COVID-19. Lifetime exposure, rather than recent infection, may be responsible for any effect of malaria on COVID-19 severity.
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Affiliation(s)
- John Woodford
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, Bethesda, MD, United States
| | - Issaka Sagara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Halimatou Diawara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Mahamadoun Hamady Assadou
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Abdoulaye Katile
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Oumar Attaher
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Djibrilla Issiaka
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Gaoussou Santara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Ibrahim H Soumbounou
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Seydou Traore
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Moussa Traore
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Oumar M Dicko
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Sidi Mohamed Niambele
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Almahamoudou Mahamar
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Bourama Kamate
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Bayaya Haidara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Kourane Sissoko
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Seydou Sankare
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Sadio Dite Koni Diarra
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Amatigue Zeguime
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Justin Y A Doritchamou
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, Bethesda, MD, United States
| | - Irfan Zaidi
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, Bethesda, MD, United States
| | - Alassane Dicko
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, Bethesda, MD, United States
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Woodford J, Sagara I, Dicko A, Duffy PE. Adapting malaria clinical trials infrastructure to implement COVID-19 epidemiology studies: Response to a public health emergency amid safe continuation of a research enterprise. Front Public Health 2022; 10:959678. [PMID: 35958840 PMCID: PMC9358281 DOI: 10.3389/fpubh.2022.959678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 07/06/2022] [Indexed: 12/01/2022] Open
Affiliation(s)
- John Woodford
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, Bethesda, MD, United States
- *Correspondence: John Woodford
| | - Issaka Sagara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Patrick E. Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, Bethesda, MD, United States
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25
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Ramjith J, Alkema M, Bradley J, Dicko A, Drakeley C, Stone W, Bousema T. Quantifying Reductions in Plasmodium falciparum Infectivity to Mosquitos: A Sample Size Calculator to Inform Clinical Trials on Transmission-Reducing Interventions. Front Immunol 2022; 13:899615. [PMID: 35720362 PMCID: PMC9205189 DOI: 10.3389/fimmu.2022.899615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 05/10/2022] [Indexed: 11/13/2022] Open
Abstract
Malaria transmission depends on the presence of mature Plasmodium transmission stages (gametocytes) that may render blood-feeding Anopheles mosquitos infectious. Transmission-blocking antimalarial drugs and vaccines can prevent transmission by reducing gametocyte densities or infectivity to mosquitos. Mosquito infection outcomes are thereby informative biological endpoints of clinical trials with transmission blocking interventions. Nevertheless, trials are often primarily designed to determine intervention safety; transmission blocking efficacy is difficult to incorporate in sample size considerations due to variation in infection outcomes and considerable inter-study variation. Here, we use clinical trial data from studies in malaria naive and naturally exposed study participants to present an online sample size calculator tool. This sample size calculator allows studies to be powered to detect reductions in the proportion of infected mosquitos or infection burden (oocyst density) in mosquitos. The utility of this online tool is illustrated using trial data with transmission blocking malaria drugs.
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Affiliation(s)
- Jordache Ramjith
- Radboud Institute for Molecular Life Sciences, Department of Medical Microbiology, Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands.,Department for Health Evidence, Biostatistics Research Group, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - Manon Alkema
- Radboud Institute for Molecular Life Sciences, Department of Medical Microbiology, Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
| | - John Bradley
- Medical Research Council (MRC) International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Alassane Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Chris Drakeley
- Medical Research Council (MRC) International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Will Stone
- Medical Research Council (MRC) International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Teun Bousema
- Radboud Institute for Molecular Life Sciences, Department of Medical Microbiology, Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
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26
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Stone W, Mahamar A, Smit MJ, Sanogo K, Sinaba Y, Niambele SM, Sacko A, Keita S, Dicko OM, Diallo M, Maguiraga SO, Samake S, Attaher O, Lanke K, Ter Heine R, Bradley J, McCall MBB, Issiaka D, Traore SF, Bousema T, Drakeley C, Dicko A. Single low-dose tafenoquine combined with dihydroartemisinin-piperaquine to reduce Plasmodium falciparum transmission in Ouelessebougou, Mali: a phase 2, single-blind, randomised clinical trial. Lancet Microbe 2022; 3:e336-e347. [PMID: 35544095 PMCID: PMC9042793 DOI: 10.1016/s2666-5247(21)00356-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 12/07/2021] [Accepted: 12/15/2021] [Indexed: 11/20/2022]
Abstract
BACKGROUND Tafenoquine was recently approved as a prophylaxis and radical cure for Plasmodium vivax infection, but its Plasmodium falciparum transmission-blocking efficacy is unclear. We aimed to establish the efficacy and safety of three single low doses of tafenoquine in combination with dihydroartemisinin-piperaquine for reducing gametocyte density and transmission to mosquitoes. METHODS In this four-arm, single-blind, phase 2, randomised controlled trial, participants were recruited at the Clinical Research Unit of the Malaria Research and Training Centre of the University of Bamako in Mali. Eligible participants were aged 12-50 years, with asymptomatic P falciparum microscopy-detected gametocyte carriage, had a bodyweight of 80 kg or less, and had no clinical signs of malaria defined by fever. Participants were randomly assigned (1:1:1:1) to standard treatment with dihydroartemisinin-piperaquine, or dihydroartemisinin-piperaquine plus a single dose of tafenoquine (in solution) at a final dosage of 0·42 mg/kg, 0·83 mg/kg, or 1·66 mg/kg. Randomisation was done with a computer-generated randomisation list and concealed with sealed, opaque envelopes. Dihydroartemisinin-piperaquine was administered as oral tablets over 3 days (day 0, 1, and 2), as per manufacturer instructions. A single dose of tafenoquine was administered as oral solution on day 0 in parallel with the first dose of dihydroartemisinin-piperaquine. Tafenoquine dosing was based on bodyweight to standardise efficacy and risk variance. The primary endpoint, assessed in the per-protocol population, was median percentage change in mosquito infection rate 7 days after treatment compared with baseline. Safety endpoints included frequency and incidence of adverse events. The final follow-up visit was on Dec 23, 2021; the trial is registered with ClinicalTrials.gov, NCT04609098. FINDINGS From Oct 29 to Nov 25, 2020, 1091 individuals were screened for eligibility, 80 of whom were enrolled and randomly assigned (20 per treatment group). Before treatment, 53 (66%) individuals were infectious to mosquitoes, infecting median 12·50% of mosquitoes (IQR 3·64-35·00). Within-group reduction in mosquito infection rate on day 7 was 79·95% (IQR 57·15-100; p=0·0005 for difference from baseline) following dihydroartemisinin-piperaquine only, 100% (98·36-100; p=0·0005) following dihydroartemisinin-piperaquine plus tafenoquine 0·42 mg/kg, 100% (100-100; p=0·0001) following dihydroartemisinin-piperaquine plus tafenoquine 0·83 mg/kg, and 100% (100-100; p=0·0001) following dihydroartemisinin-piperaquine plus tafenoquine 1·66 mg/kg. 55 (69%) of 80 participants had a total of 94 adverse events over the course of the trial; 86 (92%) adverse events were categorised as mild, seven (7%) as moderate, and one (1%) as severe. The most common treatment-related adverse event was mild or moderate headache, which occurred in 15 (19%) participants (dihydroartemisinin-piperaquine n=2; dihydroartemisinin-piperaquine plus tafenoquine 0·42 mg/kg n=6; dihydroartemisinin-piperaquine plus tafenoquine 0·83 mg/kg n=3; and dihydroartemisinin-piperaquine plus tafenoquine 1·66 mg/kg n=4). No serious adverse events occurred. No significant differences in the incidence of all adverse events (p=0·73) or treatment-related adverse events (p=0·62) were observed between treatment groups. INTERPRETATION Tafenoquine was well tolerated at all doses and accelerated P falciparum gametocyte clearance. All tafenoquine doses showed improved transmission reduction at day 7 compared with dihydroartemisinin-piperaquine alone. These data support the case for further research on tafenoquine as a transmission-blocking supplement to standard antimalarials. FUNDING Bill & Melinda Gates Foundation. TRANSLATIONS For the French, Portuguese, Spanish and Swahili translations of the abstract see Supplementary Materials section.
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Affiliation(s)
- Will Stone
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK.
| | - Almahamoudou Mahamar
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Merel J Smit
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, Netherlands
| | - Koualy Sanogo
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Youssouf Sinaba
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sidi M Niambele
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Adama Sacko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekouba Keita
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Oumar M Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Makonon Diallo
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Seydina O Maguiraga
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Siaka Samake
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Oumar Attaher
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Kjerstin Lanke
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, Netherlands
| | - Rob Ter Heine
- Department of Pharmacy and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, Netherlands
| | - John Bradley
- MRC International Statistics and Epidemiology Group, London School of Hygiene & Tropical Medicine, London, UK
| | - Matthew B B McCall
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, Netherlands
| | - Djibrilla Issiaka
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekou F Traore
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Teun Bousema
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, Netherlands
| | - Chris Drakeley
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Alassane Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
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Renn JP, Doritchamou JYA, Tentokam BCN, Morrison RD, Cowles MV, Burkhardt M, Ma R, Mahamar A, Attaher O, Diarra BS, Traore M, Dicko A, Tolia NH, Fried M, Duffy PE. Author Correction: Allelic variants of full-length VAR2CSA, the placental malaria vaccine candidate, differ in antigenicity and receptor binding affinity. Commun Biol 2022; 5:404. [PMID: 35474125 PMCID: PMC9042814 DOI: 10.1038/s42003-022-03337-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Jonathan P Renn
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Justin Y A Doritchamou
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Bergeline C Nguemwo Tentokam
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Robert D Morrison
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Matthew V Cowles
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Martin Burkhardt
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Rui Ma
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Almahamoudou Mahamar
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Oumar Attaher
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Bacary S Diarra
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Moussa Traore
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Niraj H Tolia
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
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Mahamar A, Gonzales Hurtado PA, Morrison R, Boone R, Attaher O, Diarra BS, Gaoussou S, Issiaka D, Dicko A, Duffy PE, Fried M. Plasma biomarkers of hemoglobin loss in Plasmodium falciparum-infected children identified by quantitative proteomics. Blood 2022; 139:2361-2376. [PMID: 34871370 PMCID: PMC9012130 DOI: 10.1182/blood.2021014045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/23/2021] [Indexed: 11/20/2022] Open
Abstract
Anemia is common among young children infected with Plasmodium falciparum and severe malarial anemia (SMA) is a major cause of their mortality. Two major mechanisms cause malarial anemia: hemolysis of uninfected as well as infected erythrocytes and insufficient erythropoiesis. In a longitudinal birth cohort in Mali, we commonly observed marked hemoglobin reductions during P falciparum infections with a small proportion that progressed to SMA. We sought biomarkers of these processes using quantitative proteomic analysis on plasma samples from 9 P falciparum-infected children, comparing those with reduced hemoglobin (with or without SMA) vs those with stable hemoglobin. We identified higher plasma levels of circulating 20S proteasome and lower insulin-like growth factor-1 (IGF-1) levels in children with reduced hemoglobin. We confirmed these findings in independent enzyme-linked immunosorbent assay-based validation studies of subsets of children from the same cohort (20S proteasome, N = 71; IGF-1, N = 78). We speculate that circulating 20S proteasome plays a role in digesting erythrocyte membrane proteins modified by oxidative stress, resulting in hemolysis, whereas decreased IGF-1, a critical factor for erythroid maturation, might contribute to insufficient erythropoiesis. Quantitative plasma proteomics identified soluble mediators that may contribute to the major mechanisms underlying malarial anemia. This study was registered at www.clinicaltrials.gov as #NCT01168271.
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Affiliation(s)
- Almahamoudou Mahamar
- Malaria Research and Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali; and
| | | | - Robert Morrison
- Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Rachel Boone
- Molecular Pathogenesis and Biomarkers Section and
| | - Oumar Attaher
- Malaria Research and Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali; and
| | - Bacary S Diarra
- Malaria Research and Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali; and
| | - Santara Gaoussou
- Malaria Research and Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali; and
| | - Djibrilla Issiaka
- Malaria Research and Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali; and
| | - Alassane Dicko
- Malaria Research and Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali; and
| | - Patrick E Duffy
- Pathogenesis and Immunity Section, Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Michal Fried
- Molecular Pathogenesis and Biomarkers Section and
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Van Hulle S, Sagara I, Mbodji M, Nana GI, Coulibaly M, Dicko A, Kone M, Thera I, Sylla D, Traore MD, Liu F, Grieco JP, Achee NL. Evaluation of the protective efficacy of a spatial repellent to reduce malaria incidence in children in Mali compared to placebo: study protocol for a cluster-randomized double-blinded control trial (the AEGIS program). Trials 2022; 23:259. [PMID: 35382856 PMCID: PMC8980511 DOI: 10.1186/s13063-022-06197-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 03/24/2022] [Indexed: 11/15/2022] Open
Abstract
Background Spatial repellents have been widely used for the prevention of mosquito bites but their efficacy in reducing mosquito-borne diseases has never been evaluated in Africa. Additionally, spatial repellents have the potential of being critical tools in the prevention of mosquito-borne diseases in contexts where typical vectors control efforts such as insecticide-treated nets (ITNs) and indoor residual spray (IRS) are inaccessible or underutilized such as among displaced populations or in emergency relief settings. To address this knowledge gap, Kolondieba District, Sikasso Region, Mali was selected as a site to estimate the impact of the Mosquito Shield™, a spatial repellent that incorporates transfluthrin on a plastic sheet, on malaria-related outcomes. Over the past decade, the Region of Sikasso, Health districts of Kadiolo, Yorosso, and Kolondieba have remained among the most afflicted, characterized by an annual parasite incidence of more than 116 cases per 1000 population [1] and a Plasmodium falciparum prevalence rate of 29.7% [2]. Methods Cluster-randomized, placebo-controlled, double-blinded clinical trial, whereby children ≥ 6 months to < 10 years old will be enrolled and followed to determine the time to malaria infection with monthly blood samples for microscopic diagnosis. A total of 1920 subjects (HHs) will be enrolled in 60 clusters (30 spatial repellent, 30 placebo). Malaria incidence will be estimated and compared to demonstrate and quantify the protective efficacy (PE) of a spatial repellent, in reducing malaria infection. Monthly mosquito collections using CDC light traps will be conducted to determine if there are entomological correlates of spatial repellent efficacy that may be useful for the evaluation of new spatial repellents. Quarterly human landing catches (HLC) will assess the behavioral effects of the intervention. Discussion Findings will serve as an efficacy trial of spatial repellent products for sub-Saharan Africa. Findings will be submitted to the World Health Organization Vector Control Advisory Group (WHO VCAG) for assessment of whether spatial repellents have “public health value.” Entomological outcomes will also be measured as proxies of malaria transmission to help develop guidelines for the evaluation of future spatial repellent products. Trial registration ClinicalTrials.govNCT04795648. Registered on March 12, 2021. Supplementary Information The online version contains supplementary material available at 10.1186/s13063-022-06197-w.
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Affiliation(s)
| | - Issaka Sagara
- Malaria Research and Training Center (MRTC), Faculty of Medicine, Dentistry and Pharmacy at the University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | | | | | - Mamadou Coulibaly
- Malaria Research and Training Center (MRTC), Faculty of Medicine, Dentistry and Pharmacy at the University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Center (MRTC), Faculty of Medicine, Dentistry and Pharmacy at the University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | - Mamady Kone
- Malaria Research and Training Center (MRTC), Faculty of Medicine, Dentistry and Pharmacy at the University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | - Ismaila Thera
- Malaria Research and Training Center (MRTC), Faculty of Medicine, Dentistry and Pharmacy at the University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | - Daman Sylla
- Malaria Research and Training Center (MRTC), Faculty of Medicine, Dentistry and Pharmacy at the University of Sciences, Techniques and Technologies of Bamako (USTTB), Bamako, Mali
| | | | - Fang Liu
- Department of Applied and Computational Mathematics and Statistics, University of Notre Dame, Notre Dame, IN, USA
| | - John P Grieco
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, USA.
| | - Nicole L Achee
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, USA
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Sagara I, Woodford J, Kone M, Assadou MH, Katile A, Attaher O, Zeguime A, Doucoure M, Higbee E, Lane J, Mohan R, Doritchamou J, Zaidi I, Esposito D, Kwan J, Sadtler K, Dicko A, Duffy PE. Rapidly Increasing Severe Acute Respiratory Syndrome Coronavirus 2 Seroprevalence and Limited Clinical Disease in 3 Malian Communities: A Prospective Cohort Study. Clin Infect Dis 2022; 74:1030-1038. [PMID: 34185847 PMCID: PMC8394825 DOI: 10.1093/cid/ciab589] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND The extent of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposure and transmission in Mali and the surrounding region is not well understood. We aimed to estimate the cumulative incidence of SARS-CoV-2 in 3 communities and understand factors associated with infection. METHODS Between July 2020 and January 2021, we collected blood samples and demographic, social, medical, and self-reported symptoms information from residents aged 6 months and older over 2 study visits. SARS-CoV-2 antibodies were measured using a highly specific 2-antigen enzyme-linked immunosorbent assay optimized for use in Mali. We calculated cumulative adjusted seroprevalence for each community and evaluated factors associated with serostatus at each visit by univariate and multivariate analysis. RESULTS Overall, 94.8% (2533/2672) of participants completed both study visits. A total of 31.3% (837/2672) were aged <10 years, 27.6% (737/2672) were aged 10-17 years, and 41.1% (1098/2572) were aged ≥18 years. The cumulative SARS-CoV-2 exposure rate was 58.5% (95% confidence interval, 47.5-69.4). This varied between sites and was 73.4% in the urban community of Sotuba, 53.2% in the rural town of Bancoumana, and 37.1% in the rural village of Donéguébougou. Study site and increased age were associated with serostatus at both study visits. There was minimal difference in reported symptoms based on serostatus. CONCLUSIONS The true extent of SARS-CoV-2 exposure in Mali is greater than previously reported and may now approach hypothetical "herd immunity" in urban areas. The epidemiology of the pandemic in the region may be primarily subclinical and within background illness rates.
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Affiliation(s)
- Issaka Sagara
- Malaria Research and Training Center/University of Sciences, Techniques and Techniques of Bamako, Bamako, Mali
| | - John Woodford
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Maryland, Bethesda, USA
| | - Mamady Kone
- Malaria Research and Training Center/University of Sciences, Techniques and Techniques of Bamako, Bamako, Mali
| | - Mahamadoun Hamady Assadou
- Malaria Research and Training Center/University of Sciences, Techniques and Techniques of Bamako, Bamako, Mali
| | - Abdoulaye Katile
- Malaria Research and Training Center/University of Sciences, Techniques and Techniques of Bamako, Bamako, Mali
| | - Oumar Attaher
- Malaria Research and Training Center/University of Sciences, Techniques and Techniques of Bamako, Bamako, Mali
| | - Amatigue Zeguime
- Malaria Research and Training Center/University of Sciences, Techniques and Techniques of Bamako, Bamako, Mali
| | - M’Bouye Doucoure
- Malaria Research and Training Center/University of Sciences, Techniques and Techniques of Bamako, Bamako, Mali
| | - Emily Higbee
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Maryland, Bethesda, USA
| | - Jacquelyn Lane
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Maryland, Bethesda, USA
| | - Rathy Mohan
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Maryland, Bethesda, USA
| | - Justin Doritchamou
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Maryland, Bethesda, USA
| | - Irfan Zaidi
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Maryland, Bethesda, USA
| | - Dominic Esposito
- Frederick National Laboratory for Cancer Research, National Institutes of Health, Maryland, Frederick, USA
| | - Jennifer Kwan
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Maryland, Bethesda, USA
| | - Kaitlyn Sadtler
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Maryland, Bethesda, USA
| | - Alassane Dicko
- Malaria Research and Training Center/University of Sciences, Techniques and Techniques of Bamako, Bamako, Mali
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Maryland, Bethesda, USA
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Abstract
The populations of moderate or highly malaria endemic areas gradually acquire some immunity to malaria as a result of repeated exposure to the infection. When this exposure is reduced as a result of effective malaria control measures, subjects who benefitted from the intervention may consequently be at increased risk of malaria if the intervention is withdrawn, especially if this is done abruptly, and an effective malaria vector remains. There have been many examples of this occurring in the past, a phenomenon often termed ‘rebound malaria’, with the incidence of malaria rebounding to the level present before the intervention was introduced. Because the main clinical burden of malaria in areas with a high level of malaria transmission is in young children, malaria control efforts have, in recent decades, focussed on this group, with substantial success being obtained with interventions such as insecticide treated mosquito nets, chemoprevention and, most recently, malaria vaccines. These are interventions whose administration may not be sustained. This has led to concerns that in these circumstances, the overall burden of malaria in children may not be reduced but just delayed, with the main period of risk being in the period shortly after the intervention is no longer given. Although dependent on the same underlying process as classical ‘resurgent’ malaria, it may be helpful to differentiate the two conditions, describing the later as ‘delayed malaria’. In this paper, some of the evidence that delayed malaria occurs is discussed and potential measures for reducing its impact are suggested.
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Affiliation(s)
- Brian Greenwood
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London, WC1E 7HT, UK.
| | - Issaka Zongo
- Institut de Recherche en Science de La Santé, Bobo-Dioulasso, Burkina Faso
| | - Alassane Dicko
- Malaria Research and Training Centre, University of Sciences Techniques and Technologies, Bamako, Mali
| | - Daniel Chandramohan
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London, WC1E 7HT, UK
| | - Robert W Snow
- Kenya Medical Research Institute-Wellcome Trust Collaborative Programme, Nairobi, Kenya.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
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Grant J, Sagara I, Zongo I, Cairns M, Yerbanga RS, Diarra M, Zoungrana C, Issiaka D, Nikièma F, Sompougdou F, Tapily A, Kaya M, Haro A, Sanogo K, Sienou AA, Traore S, Thera I, Yalcouye H, Kuepfer I, Snell P, Milligan P, Ockenhouse C, Ofori-Anyinam O, Tinto H, Djimde A, Chandramohan D, Greenwood B, Dicko A, Ouédraogo JB. Impact of seasonal RTS,S/AS01 E vaccination plus seasonal malaria chemoprevention on the nutritional status of children in Burkina Faso and Mali. Malar J 2022; 21:59. [PMID: 35193608 PMCID: PMC8864823 DOI: 10.1186/s12936-022-04077-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/06/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A recent trial in Burkina Faso and Mali showed that combining seasonal RTS,S/AS01E malaria vaccination with seasonal malaria chemoprevention (SMC) substantially reduced the incidence of uncomplicated and severe malaria in young children compared to either intervention alone. Given the possible negative effect of malaria on nutrition, the study investigated whether these children also experienced lower prevalence of acute and chronic malnutrition. METHODS In Burkina Faso and Mali 5920 children were randomized to receive either SMC alone, RTS,S/AS01E alone, or SMC combined with RTS,S/AS01E for three malaria transmission seasons (2017-2019). After each transmission season, anthropometric measurements were collected from all study children at a cross-sectional survey and used to derive nutritional status indicators, including the binary variables wasted and stunted (weight-for-height and height-for-age z-scores below - 2, respectively). Binary and continuous outcomes between treatment groups were compared by Poisson and linear regression. RESULTS In 2017, compared to SMC alone, the combined intervention reduced the prevalence of wasting by approximately 12% [prevalence ratio (PR) = 0.88 (95% CI 0.75, 1.03)], and approximately 21% in 2018 [PR = 0.79 (95% CI 0.62, 1.01)]. Point estimates were similar for comparisons with RTS,S/AS01E, but there was stronger evidence of a difference. There was at least a 30% reduction in the point estimates for the prevalence of severe wasting in the combined group compared to the other two groups in 2017 and 2018. There was no difference in the prevalence of moderate or severe wasting between the groups in 2019. The prevalence of stunting, low-MUAC-for-age or being underweight did not differ between groups for any of the three years. The prevalence of severe stunting was higher in the combined group compared to both other groups in 2018, and compared to RTS,S/AS01E alone in 2017; this observation does not have an obvious explanation and may be a chance finding. Overall, malnutrition was very common in this cohort, but declined over the study as the children became older. CONCLUSIONS Despite a high burden of malnutrition and malaria in the study populations, and a major reduction in the incidence of malaria in children receiving both interventions, this had only a modest impact on nutritional status. Therefore, other interventions are needed to reduce the high burden of malnutrition in these areas. TRIAL REGISTRATION https://www.clinicaltrials.gov/ct2/show/NCT03143218 , registered 8th May 2017.
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Affiliation(s)
- Jane Grant
- London School of Hygiene and Tropical Medicine, Keppel St., London, WC1E 7HT, UK.
| | - Issaka Sagara
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Issaka Zongo
- Institut de Recherche en Sciences de La Santé, Bobo-Dioulasso, Burkina Faso
| | - Matthew Cairns
- London School of Hygiene and Tropical Medicine, Keppel St., London, WC1E 7HT, UK
| | | | - Modibo Diarra
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Charles Zoungrana
- Institut de Recherche en Sciences de La Santé, Bobo-Dioulasso, Burkina Faso
| | - Djibrilla Issiaka
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Frédéric Nikièma
- Institut de Recherche en Sciences de La Santé, Bobo-Dioulasso, Burkina Faso
| | | | - Amadou Tapily
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Mahamadou Kaya
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Alassane Haro
- Institut de Recherche en Sciences de La Santé, Bobo-Dioulasso, Burkina Faso
| | - Koualy Sanogo
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Abdoul Aziz Sienou
- Institut de Recherche en Sciences de La Santé, Bobo-Dioulasso, Burkina Faso
| | - Seydou Traore
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Ismaila Thera
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Hama Yalcouye
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Irene Kuepfer
- London School of Hygiene and Tropical Medicine, Keppel St., London, WC1E 7HT, UK
| | - Paul Snell
- London School of Hygiene and Tropical Medicine, Keppel St., London, WC1E 7HT, UK
| | - Paul Milligan
- London School of Hygiene and Tropical Medicine, Keppel St., London, WC1E 7HT, UK
| | | | | | - Halidou Tinto
- Institut de Recherche en Sciences de La Santé, Bobo-Dioulasso, Burkina Faso
| | - Abdoulaye Djimde
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Daniel Chandramohan
- London School of Hygiene and Tropical Medicine, Keppel St., London, WC1E 7HT, UK
| | - Brian Greenwood
- London School of Hygiene and Tropical Medicine, Keppel St., London, WC1E 7HT, UK
| | - Alassane Dicko
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
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Mahamar A, Sumner KM, Levitt B, Freedman B, Traore A, Barry A, Issiaka D, Dembele AB, Kanoute MB, Attaher O, Diarra BN, Sagara I, Djimde A, Duffy PE, Fried M, Taylor SM, Dicko A. Effect of three years' seasonal malaria chemoprevention on molecular markers of resistance of Plasmodium falciparum to sulfadoxine-pyrimethamine and amodiaquine in Ouelessebougou, Mali. Malar J 2022; 21:39. [PMID: 35135546 PMCID: PMC8822718 DOI: 10.1186/s12936-022-04059-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 01/21/2022] [Indexed: 11/11/2022] Open
Abstract
Background In 2012, seasonal malaria chemoprevention (SMC) was recommended as policy for malaria control by the World Health Organization (WHO) in areas of highly seasonal malaria transmission across the Sahel sub-region in Africa along with monitoring of drug resistance. We assessed the long-term impact of SMC on Plasmodium falciparum resistance to sulfadoxine-pyrimethamine (SP) and amodiaquine (AQ) over a 3-year period of SMC implementation in the health district of Ouelessebougou, Mali. Methods In 8 randomly selected sub-districts of Ouelessebougou, Mali, children aged 0–5 years were randomly selected during cross-sectional surveys at baseline (August 2014) and 1, 2 and 3 years post-SMC, at the beginning and end of the malaria transmission season. Blood smears and blood spots on filter paper were obtained and frequencies of mutation in P. falciparum genes related to resistance to SP and AQ (Pfdhfr, Pfdhps, Pfmdr1, and Pfcrt) were assessed by PCR amplification on individual samples and PCR amplification followed by deep sequencing on pooled (by site and year) samples. Results At each survey, approximately 50–100 individual samples were analysed by PCR amplification and a total of 1,164 samples were analysed by deep sequencing with an average read depth of 18,018–36,918 after pooling by site and year. Most molecular markers of resistance did not increase in frequency over the period of study (2014–2016). After 3 years of SMC, the frequencies of Pfdhps 540E, Pfdhps 437G and Pfcrt K76T remained similar compared to baseline (4.0 vs 1.4%, p = 0.41; 74.5 vs 64.6%, p = 0.22; 71.3 vs 67.4%, p = 0.69). Nearly all samples tested carried Pfdhfr 59R, and this proportion remained similar 3 years after SMC implementation (98.8 vs 100%, p = 1). The frequency of Pfmdr1 N86Y increased significantly over time from 5.6% at baseline to 18.6% after 3 years of SMC (p = 0.016). Results of pooled analysis using deep sequencing were consistent with those by individual analysis with standard PCR, but also indicated for the first time the presence of mutations at the Pfdhps A581G allele at a frequency of 11.7% after 2 years of SMC, as well as the Pfdhps I431V allele at frequencies of 1.6–9.3% following 1 and 2 years of SMC, respectively. Conclusion Two and 3 years of SMC implementation were associated with increased frequency of the Pfmdr1 N86Y mutation but not Pfdhps 540E, Pfdhps 437G and Pfcrt K76T. The first-time detection of the Pfdhps haplotype bearing the I431V and A581G mutations in Mali, even at low frequency, warrants further long-term surveillance.
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Affiliation(s)
- Almahamoudou Mahamar
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Science, Techniques and Technologies (USTT), Bamako, Mali.
| | - Kelsey M Sumner
- Division of Infectious Diseases, Duke University Medical Center, Durham, NC, USA.,Department of Epidemiology, UNC Gillings School of Global Public Health, Chapel Hill, NC, USA
| | - Brandt Levitt
- Division of Infectious Diseases, Duke University Medical Center, Durham, NC, USA
| | - Betsy Freedman
- Division of Infectious Diseases, Duke University Medical Center, Durham, NC, USA
| | - Aliou Traore
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Science, Techniques and Technologies (USTT), Bamako, Mali
| | - Amadou Barry
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Science, Techniques and Technologies (USTT), Bamako, Mali
| | - Djibrilla Issiaka
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Science, Techniques and Technologies (USTT), Bamako, Mali
| | - Adama B Dembele
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Science, Techniques and Technologies (USTT), Bamako, Mali
| | - Moussa B Kanoute
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Science, Techniques and Technologies (USTT), Bamako, Mali
| | - Oumar Attaher
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Science, Techniques and Technologies (USTT), Bamako, Mali
| | | | - Issaka Sagara
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Science, Techniques and Technologies (USTT), Bamako, Mali
| | - Abdoulaye Djimde
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Science, Techniques and Technologies (USTT), Bamako, Mali
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology (LMIV), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology (LMIV), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Steve M Taylor
- Division of Infectious Diseases, Duke University Medical Center, Durham, NC, USA.,Duke Global Health Institute, Duke University, Durham, NC, USA
| | - Alassane Dicko
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Science, Techniques and Technologies (USTT), Bamako, Mali
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Stone W, Mahamar A, Sanogo K, Sinaba Y, Niambele SM, Sacko A, Keita S, Youssouf A, Diallo M, Soumare HM, Kaur H, Lanke K, ter Heine R, Bradley J, Issiaka D, Diawara H, Traore SF, Bousema T, Drakeley C, Dicko A. Pyronaridine–artesunate or dihydroartemisinin–piperaquine combined with single low-dose primaquine to prevent Plasmodium falciparum malaria transmission in Ouélessébougou, Mali: a four-arm, single-blind, phase 2/3, randomised trial. The Lancet Microbe 2022; 3:e41-e51. [PMID: 35028628 PMCID: PMC8721154 DOI: 10.1016/s2666-5247(21)00192-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- William Stone
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
- Correspondence to: Dr William Stone, Department of Infection Biology, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
| | - Almahamoudou Mahamar
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Koualy Sanogo
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Youssouf Sinaba
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sidi M Niambele
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Adama Sacko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekouba Keita
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Ahamadou Youssouf
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Makonon Diallo
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Harouna M Soumare
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Harparkash Kaur
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Kjerstin Lanke
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, Netherlands
| | - Rob ter Heine
- Department of Pharmacy and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, Netherlands
| | - John Bradley
- MRC International Statistics and Epidemiology Group, London School of Hygiene & Tropical Medicine, London, UK
| | - Djibrilla Issiaka
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Halimatou Diawara
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Sekou F Traore
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
| | - Teun Bousema
- Department of Medical Microbiology and Radboud Center for Infectious Diseases, Radboud University Medical Center, University of Nijmegen, Nijmegen, Netherlands
| | - Chris Drakeley
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, UK
| | - Alassane Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, Bamako, Mali
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35
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Woodford J, Sagara I, Dicko A, Zeguime A, Doucoure M, Kwan J, Zaidi I, Doritchamou J, Snow-Smith M, Alani N, Renn J, Kosik I, Holly J, Yewdell J, Esposito D, Sadtler K, Duffy P. Severe Acute Respiratory Syndrome Coronavirus 2 Seroassay Performance and Optimization in a Population With High Background Reactivity in Mali. J Infect Dis 2021; 224:2001-2009. [PMID: 34612499 PMCID: PMC8522418 DOI: 10.1093/infdis/jiab498] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 10/04/2021] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND False positivity may hinder the utility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests in sub-Saharan Africa. METHODS From 312 Malian samples collected before 2020, we measured antibodies to the commonly tested SARS-CoV-2 antigens and 4 other betacoronaviruses by enzyme-linked immunosorbent assay (ELISA). In a subset of samples, we assessed antibodies to a panel of Plasmodium falciparum antigens by suspension bead array and functional antiviral activity by SARS-CoV-2 pseudovirus neutralization assay. We then evaluated the performance of an ELISA using SARS-CoV-2 spike protein and receptor-binding domain developed in the United States using Malian positive and negative control samples. To optimize test performance, we compared single- and 2-antigen approaches using existing assay cutoffs and population-specific cutoffs. RESULTS Background reactivity to SARS-CoV-2 antigens was common in prepandemic Malian samples. The SARS-CoV-2 reactivity varied between communities, increased with age, and correlated negligibly/weakly with other betacoronavirus and P falciparum antibodies. No prepandemic samples demonstrated functional activity. Regardless of the cutoffs applied, test specificity improved using a 2-antigen approach. Test performance was optimal using a 2-antigen assay with population-specific cutoffs (sensitivity, 73.9% [95% confidence interval {CI}, 51.6-89.8]; specificity, 99.4% [95% CI, 97.7-99.9]). CONCLUSIONS We have addressed the problem of SARS-CoV-2 seroassay performance in Africa by using a 2-antigen assay with cutoffs defined by performance in the target population.
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Affiliation(s)
- John Woodford
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Issaka Sagara
- Malaria Research and Training Center/University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Center/University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Amatigue Zeguime
- Malaria Research and Training Center/University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - M’Bouye Doucoure
- Malaria Research and Training Center/University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Jennifer Kwan
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Irfan Zaidi
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Justin Doritchamou
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Maryonne Snow-Smith
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Nada Alani
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jonathan Renn
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Ivan Kosik
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jaroslav Holly
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jonathan Yewdell
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Dominic Esposito
- Frederick National Laboratory for Cancer Research, National Institutes of Health, Frederick, Maryland, USA
| | - Kaitlyn Sadtler
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
| | - Patrick Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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36
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Woodford J, Sagara I, Dicko A, Zeguime A, Doucoure M, Kwan J, Zaidi I, Doritchamou J, Snow-Smith M, Alani N, Renn J, Kosik I, Holly J, Yewdell J, Esposito D, Sadtler K, Duffy P. Severe Acute Respiratory Syndrome Coronavirus 2 Seroassay Performance and Optimization in a Population With High Background Reactivity in Mali. J Infect Dis 2021. [PMID: 34612499 DOI: 10.1101/2021.03.08.21252784v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023] Open
Abstract
BACKGROUND False positivity may hinder the utility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests in sub-Saharan Africa. METHODS From 312 Malian samples collected before 2020, we measured antibodies to the commonly tested SARS-CoV-2 antigens and 4 other betacoronaviruses by enzyme-linked immunosorbent assay (ELISA). In a subset of samples, we assessed antibodies to a panel of Plasmodium falciparum antigens by suspension bead array and functional antiviral activity by SARS-CoV-2 pseudovirus neutralization assay. We then evaluated the performance of an ELISA using SARS-CoV-2 spike protein and receptor-binding domain developed in the United States using Malian positive and negative control samples. To optimize test performance, we compared single- and 2-antigen approaches using existing assay cutoffs and population-specific cutoffs. RESULTS Background reactivity to SARS-CoV-2 antigens was common in prepandemic Malian samples. The SARS-CoV-2 reactivity varied between communities, increased with age, and correlated negligibly/weakly with other betacoronavirus and P falciparum antibodies. No prepandemic samples demonstrated functional activity. Regardless of the cutoffs applied, test specificity improved using a 2-antigen approach. Test performance was optimal using a 2-antigen assay with population-specific cutoffs (sensitivity, 73.9% [95% confidence interval {CI}, 51.6-89.8]; specificity, 99.4% [95% CI, 97.7-99.9]). CONCLUSIONS We have addressed the problem of SARS-CoV-2 seroassay performance in Africa by using a 2-antigen assay with cutoffs defined by performance in the target population.
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Affiliation(s)
- John Woodford
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Issaka Sagara
- Malaria Research and Training Center/University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Center/University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Amatigue Zeguime
- Malaria Research and Training Center/University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - M'Bouye Doucoure
- Malaria Research and Training Center/University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Jennifer Kwan
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Irfan Zaidi
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Justin Doritchamou
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Maryonne Snow-Smith
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Nada Alani
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jonathan Renn
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Ivan Kosik
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jaroslav Holly
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jonathan Yewdell
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Dominic Esposito
- Frederick National Laboratory for Cancer Research, National Institutes of Health, Frederick, Maryland, USA
| | - Kaitlyn Sadtler
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, USA
| | - Patrick Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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Chotsiri P, Mahamar A, Hoglund RM, Koita F, Sanogo K, Diawara H, Dicko A, Simpson JA, Bousema T, White NJ, Brown JM, Gosling R, Chen I, Tarning J. Mechanistic Modelling of Primaquine Pharmacokinetics, Gametocytocidal Activity, and Mosquito Infectivity. Clin Pharmacol Ther 2021; 111:676-685. [PMID: 34905220 PMCID: PMC9302630 DOI: 10.1002/cpt.2512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 12/08/2021] [Indexed: 11/06/2022]
Abstract
Clinical studies have shown that adding a single 0.25mg base/kg dose of primaquine to standard antimalarial regimens rapidly sterilises Plasmodium falciparum gametocytes. However, the mechanism of action and overall impact on malaria transmission is still unknown. Using data from 81 adult Malians with P. falciparum gametocytaemia who received the standard dihydroartemisinin-piperaquine treatment course and were randomised to receive either a single dose of primaquine between 0.0625 and 0.5 mg base/kg or placebo. We characterised the pharmacokinetic-pharmacodynamic relationships for transmission blocking activity. Both gametocyte clearance and mosquito infectivity were assessed. A mechanistically-linked pharmacokinetic-pharmacodynamic model adequately described primaquine and carboxy-primaquine pharmacokinetics, gametocyte dynamics, and mosquito infectivity at different clinical doses of primaquine. Primaquine showed a dose-dependent gametocytocidal effect that precedes clearance. A single low dose of primaquine (0.25 mg/kg) rapidly prevented P. falciparum transmissibility.
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Affiliation(s)
- Palang Chotsiri
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Almahamoudou Mahamar
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Science, Techniques and Technologies of Namako, Bamako, Mali
| | - Richard M Hoglund
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, UK
| | - Fanta Koita
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Science, Techniques and Technologies of Namako, Bamako, Mali
| | - Koualy Sanogo
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Science, Techniques and Technologies of Namako, Bamako, Mali
| | - Halimatou Diawara
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Science, Techniques and Technologies of Namako, Bamako, Mali
| | - Alassane Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Science, Techniques and Technologies of Namako, Bamako, Mali
| | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia
| | - Teun Bousema
- Radboud Institute of Health Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - Nicholas J White
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, UK
| | - Joelle M Brown
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA
| | - Roly Gosling
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA.,Global Health Group, Malaria Elimination Initiative, University of California, San Francisco, CA, USA
| | - Ingrid Chen
- Global Health Group, Malaria Elimination Initiative, University of California, San Francisco, CA, USA
| | - Joel Tarning
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, UK
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38
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Woodford J, Sagara I, Kwan J, Zaidi I, Dicko A, Duffy PE. Assessing and Minimizing the Effect of Malaria on SARS-CoV-2 Serodiagnostics. Front Trop Dis 2021. [DOI: 10.3389/fitd.2021.781586] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Malaria may affect the reliability of SARS-CoV-2 seroassay performance and limit understanding of SARS-CoV-2 epidemiology in malaria-endemic regions. We present our experience conducting SARS-CoV-2 serosurveillance in seasonal malaria-affected communities in Mali and discuss relevant literature regarding the effect of malaria on the performance of SARS-CoV-2 serodiagnostics, including approaches to minimize the effect of malaria-associated assay interference.
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39
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Phiri MD, Cairns M, Zongo I, Nikiema F, Diarra M, Yerbanga RS, Barry A, Tapily A, Coumare S, Thera I, Kuepfer I, Milligan P, Tinto H, Dicko A, Ouédraogo JB, Greenwood B, Chandramohan D, Sagara I. The Duration of Protection from Azithromycin Against Malaria, Acute Respiratory, Gastrointestinal, and Skin Infections When Given Alongside Seasonal Malaria Chemoprevention: Secondary Analyses of Data from a Clinical Trial in Houndé, Burkina Faso, and Bougouni, Mali. Clin Infect Dis 2021; 73:e2379-e2386. [PMID: 33417683 PMCID: PMC8492219 DOI: 10.1093/cid/ciaa1905] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Mass drug administration (MDA) with azithromycin (AZ) is being considered as a strategy to promote child survival in sub-Saharan Africa, but the mechanism by which AZ reduces mortality is unclear. To better understand the nature and extent of protection provided by AZ, we explored the profile of protection by time since administration, using data from a household-randomized, placebo-controlled trial in Burkina Faso and Mali. METHODS Between 2014 and 2016, 30 977 children aged 3-59 months received seasonal malaria chemoprevention (SMC) with sulfadoxine-pyrimethamine plus amodiaquine and either AZ or placebo monthly, on 4 occasions each year. Poisson regression with gamma-distributed random effects, accounting for the household randomization and within-individual clustering of illness episodes, was used to compare incidence of prespecified outcomes between SMC+AZ versus SMC+placebo groups in fixed time strata post-treatment. The likelihood ratio test was used to assess evidence for a time-treatment group interaction. RESULTS Relative to SMC+placebo, there was no evidence of protection from SMC+AZ against hospital admissions and deaths. Additional protection from SMC+AZ against malaria was confined to the first 2 weeks post-administration (protective efficacy (PE): 24.2% [95% CI: 17.8%, 30.1%]). Gastroenteritis and pneumonia were reduced by 29.9% [21.7; 37.3%], and 34.3% [14.9; 49.3%], respectively, in the first 2 weeks postadministration. Protection against nonmalaria fevers with a skin condition persisted up to 28 days: PE: 46.3% [35.1; 55.6%]. CONCLUSIONS The benefits of AZ-MDA are broad-ranging but short-lived. To maximize impact, timing of AZ-MDA must address the challenge of targeting asynchronous morbidity and mortality peaks from different causes.
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Affiliation(s)
- Mphatso Dennis Phiri
- Malaria Epidemiology Group, Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Matthew Cairns
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Issaka Zongo
- Le Département Biomédical et de Santé Publique, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Frederic Nikiema
- Le Département Biomédical et de Santé Publique, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Modibo Diarra
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Rakiswendé Serge Yerbanga
- Le Département Biomédical et de Santé Publique, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Amadou Barry
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Amadou Tapily
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Samba Coumare
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Ismaila Thera
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Irene Kuepfer
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Paul Milligan
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Halidou Tinto
- Le Département Biomédical et de Santé Publique, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Alassane Dicko
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Jean Bosco Ouédraogo
- Le Département Biomédical et de Santé Publique, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Brian Greenwood
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Daniel Chandramohan
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Issaka Sagara
- Malaria Research and Training Center, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
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Chandramohan D, Zongo I, Sagara I, Cairns M, Yerbanga RS, Diarra M, Nikièma F, Tapily A, Sompougdou F, Issiaka D, Zoungrana C, Sanogo K, Haro A, Kaya M, Sienou AA, Traore S, Mahamar A, Thera I, Diarra K, Dolo A, Kuepfer I, Snell P, Milligan P, Ockenhouse C, Ofori-Anyinam O, Tinto H, Djimde A, Ouédraogo JB, Dicko A, Greenwood B. Seasonal Malaria Vaccination with or without Seasonal Malaria Chemoprevention. N Engl J Med 2021; 385:1005-1017. [PMID: 34432975 DOI: 10.1056/nejmoa2026330] [Citation(s) in RCA: 95] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Malaria control remains a challenge in many parts of the Sahel and sub-Sahel regions of Africa. METHODS We conducted an individually randomized, controlled trial to assess whether seasonal vaccination with RTS,S/AS01E was noninferior to chemoprevention in preventing uncomplicated malaria and whether the two interventions combined were superior to either one alone in preventing uncomplicated malaria and severe malaria-related outcomes. RESULTS We randomly assigned 6861 children 5 to 17 months of age to receive sulfadoxine-pyrimethamine and amodiaquine (2287 children [chemoprevention-alone group]), RTS,S/AS01E (2288 children [vaccine-alone group]), or chemoprevention and RTS,S/AS01E (2286 children [combination group]). Of these, 1965, 1988, and 1967 children in the three groups, respectively, received the first dose of the assigned intervention and were followed for 3 years. Febrile seizure developed in 5 children the day after receipt of the vaccine, but the children recovered and had no sequelae. There were 305 events of uncomplicated clinical malaria per 1000 person-years at risk in the chemoprevention-alone group, 278 events per 1000 person-years in the vaccine-alone group, and 113 events per 1000 person-years in the combination group. The hazard ratio for the protective efficacy of RTS,S/AS01E as compared with chemoprevention was 0.92 (95% confidence interval [CI], 0.84 to 1.01), which excluded the prespecified noninferiority margin of 1.20. The protective efficacy of the combination as compared with chemoprevention alone was 62.8% (95% CI, 58.4 to 66.8) against clinical malaria, 70.5% (95% CI, 41.9 to 85.0) against hospital admission with severe malaria according to the World Health Organization definition, and 72.9% (95% CI, 2.9 to 92.4) against death from malaria. The protective efficacy of the combination as compared with the vaccine alone against these outcomes was 59.6% (95% CI, 54.7 to 64.0), 70.6% (95% CI, 42.3 to 85.0), and 75.3% (95% CI, 12.5 to 93.0), respectively. CONCLUSIONS Administration of RTS,S/AS01E was noninferior to chemoprevention in preventing uncomplicated malaria. The combination of these interventions resulted in a substantially lower incidence of uncomplicated malaria, severe malaria, and death from malaria than either intervention alone. (Funded by the Joint Global Health Trials and PATH; ClinicalTrials.gov number, NCT03143218.).
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Affiliation(s)
- Daniel Chandramohan
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Issaka Zongo
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Issaka Sagara
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Matthew Cairns
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Rakiswendé-Serge Yerbanga
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Modibo Diarra
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Frédéric Nikièma
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Amadou Tapily
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Frédéric Sompougdou
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Djibrilla Issiaka
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Charles Zoungrana
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Koualy Sanogo
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Alassane Haro
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Mahamadou Kaya
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Abdoul-Aziz Sienou
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Seydou Traore
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Almahamoudou Mahamar
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Ismaila Thera
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Kalifa Diarra
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Amagana Dolo
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Irene Kuepfer
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Paul Snell
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Paul Milligan
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Christian Ockenhouse
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Opokua Ofori-Anyinam
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Halidou Tinto
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Abdoulaye Djimde
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Jean-Bosco Ouédraogo
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Alassane Dicko
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
| | - Brian Greenwood
- From the London School of Hygiene and Tropical Medicine, London (D.C., M.C., I.K., P.S., P.M., B.G.); Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso (I.Z., R.-S.Y., F.N., F.S., C.Z., A.H., A.-A.S., H.T., J.-B.O.); the Malaria Research and Training Center, University of Sciences, Technologies, and Techniques of Bamako, Bamako, Mali (I.S., M.D., A.T., D.I., K.S., M.K., S.T., A.M., I.T., K.D., A. Dolo, A. Djimde, A. Dicko); PATH, Seattle (C.O.); and GlaxoSmithKline Vaccines, Rixensart, Belgium (O.O.-A.)
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Greenwood B, Cairns M, Chaponda M, Chico RM, Dicko A, Ouedraogo JB, Phiri KS, Ter Kuile FO, Chandramohan D. Combining malaria vaccination with chemoprevention: a promising new approach to malaria control. Malar J 2021; 20:361. [PMID: 34488784 PMCID: PMC8419817 DOI: 10.1186/s12936-021-03888-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 08/20/2021] [Indexed: 11/13/2022] Open
Abstract
Malaria control has stalled in a number of African countries and novel approaches to malaria control are needed for these areas. The encouraging results of a recent trial conducted in young children in Burkina Faso and Mali in which a combination of the RTS,S/AS01E malaria vaccine and seasonal malaria chemoprevention led to a substantial reduction in clinical cases of malaria, severe malaria, and malaria deaths compared with the administration of either intervention given alone suggests that there may be other epidemiological/clinical situations in which a combination of malaria vaccination and chemoprevention could be beneficial. Some of these potential opportunities are considered in this paper. These include combining vaccination with intermittent preventive treatment of malaria in infants, with intermittent preventive treatment of malaria in pregnancy (through vaccination of women of child-bearing age before or during pregnancy), or with post-discharge malaria chemoprevention in the management of children recently admitted to hospital with severe anaemia. Other potential uses of the combination are prevention of malaria in children at particular risk from the adverse effects of clinical malaria, such as those with sickle cell disease, and during the final stages of a malaria elimination programme when vaccination could be combined with repeated rounds of mass drug administration. The combination of a pre-erythrocytic stage malaria vaccine with an effective chemopreventive regimen could make a valuable contribution to malaria control and elimination in a variety of clinical or epidemiological situations, and the potential of this approach to malaria control needs to be explored.
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Affiliation(s)
| | - Matthew Cairns
- London School of Hygiene and Tropical Medicine, London, UK
| | | | | | - Alassane Dicko
- Malaria Research and Training Centre, University of Science, Techniques and Technology of Bamako, Bamako, Mali
| | | | - Kamija S Phiri
- School of Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
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Cairns M, Ceesay SJ, Sagara I, Zongo I, Kessely H, Gamougam K, Diallo A, Ogboi JS, Moroso D, Van Hulle S, Eloike T, Snell P, Scott S, Merle C, Bojang K, Ouedraogo JB, Dicko A, Ndiaye JL, Milligan P. Effectiveness of seasonal malaria chemoprevention (SMC) treatments when SMC is implemented at scale: Case-control studies in 5 countries. PLoS Med 2021; 18:e1003727. [PMID: 34495978 PMCID: PMC8457484 DOI: 10.1371/journal.pmed.1003727] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 09/22/2021] [Accepted: 07/12/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Seasonal malaria chemoprevention (SMC) has shown high protective efficacy against clinical malaria and severe malaria in a series of clinical trials. We evaluated the effectiveness of SMC treatments against clinical malaria when delivered at scale through national malaria control programmes in 2015 and 2016. METHODS AND FINDINGS Case-control studies were carried out in Mali and The Gambia in 2015, and in Burkina Faso, Chad, Mali, Nigeria, and The Gambia in 2016. Children aged 3-59 months presenting at selected health facilities with microscopically confirmed clinical malaria were recruited as cases. Two controls per case were recruited concurrently (on or shortly after the day the case was detected) from the neighbourhood in which the case lived. The primary exposure was the time since the most recent course of SMC treatment, determined from SMC recipient cards, caregiver recall, and administrative records. Conditional logistic regression was used to estimate the odds ratio (OR) associated with receipt of SMC within the previous 28 days, and SMC 29 to 42 days ago, compared with no SMC in the past 42 days. These ORs, which are equivalent to incidence rate ratios, were used to calculate the percentage reduction in clinical malaria incidence in the corresponding time periods. Results from individual countries were pooled in a random-effects meta-analysis. In total, 2,126 cases and 4,252 controls were included in the analysis. Across the 7 studies, the mean age ranged from 1.7 to 2.4 years and from 2.1 to 2.8 years among controls and cases, respectively; 42.2%-50.9% and 38.9%-46.9% of controls and cases, respectively, were male. In all 7 individual case-control studies, a high degree of personal protection from SMC against clinical malaria was observed, ranging from 73% in Mali in 2016 to 98% in Mali in 2015. The overall OR for SMC within 28 days was 0.12 (95% CI: 0.06, 0.21; p < 0.001), indicating a protective effectiveness of 88% (95% CI: 79%, 94%). Effectiveness against clinical malaria for SMC 29-42 days ago was 61% (95% CI: 47%, 72%). Similar results were obtained when the analysis was restricted to cases with parasite density in excess of 5,000 parasites per microlitre: Protective effectiveness 90% (95% CI: 79%, 96%; P<0.001), and 59% (95% CI: 34%, 74%; P<0.001) for SMC 0-28 days and 29-42 days ago, respectively. Potential limitations include the possibility of residual confounding due to an association between exposure to malaria and access to SMC, or differences in access to SMC between patients attending a clinic and community controls; however, neighbourhood matching of cases and controls, and covariate adjustment, attempted to control for these aspects, and the observed decline in protection over time, consistent with expected trends, argues against a major bias from these sources. CONCLUSIONS SMC administered as part of routine national malaria control activities provided a very high level of personal protection against clinical malaria over 28 days post-treatment, similar to the efficacy observed in clinical trials. The case-control design used in this study can be used at intervals to ensure SMC treatments remain effective.
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Affiliation(s)
- Matthew Cairns
- International Statistics and Epidemiology Group, London School of Hygiene & Tropical Medicine, London, United Kingdom
- * E-mail:
| | - Serign Jawo Ceesay
- Medical Research Council Unit The Gambia, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - Issaka Zongo
- Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Hamit Kessely
- Centre de Support en Santé Internationale, N’Djamena, Chad
| | | | | | | | | | | | - Tony Eloike
- Jedima International Health Consult, Lagos, Nigeria
| | - Paul Snell
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Susana Scott
- International Statistics and Epidemiology Group, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Corinne Merle
- Special Programme for Research and Training in Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Kalifa Bojang
- Medical Research Council Unit The Gambia, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | - Jean-Louis Ndiaye
- Universite Cheikh Anta Diop, Dakar, Senegal
- University of Thies, Thies, Senegal
| | - Paul Milligan
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
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Dahourou LD, Konaté A, Tapsoba ASR, Dicko A, Sanou M, Tamboura HH, Bayala B, Salissou I, Traoré A, Logan LL, Tembely S. Epidemiology and spatio-temporal distribution of gastrointestinal parasites infection and accuracy of FAMACHA test in sheep in traditional farming systems in Burkina Faso. Trop Anim Health Prod 2021; 53:392. [PMID: 34231076 DOI: 10.1007/s11250-021-02810-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 04/19/2021] [Indexed: 11/26/2022]
Abstract
Blood and faecal samples from 2086 Sahelian and Djallonke sheep have been collected to assess the epidemiology and spatio-temporal distribution of gastrointestinal parasites. A survey with a questionnaire allowed collecting data on individual animal and farms. Faecal samples were analysed using the McMaster technique, while anaemia was assessed using FAMACHA score test and packed cell volume. The overall prevalence of gastrointestinal parasites was 91%, and strongyles (70.7%), Eimeria sp. (60.4%), Moniezia sp. (5.7%), Stronyloides sp. (0.9%) were identified. There was no significant association between the region and strongyles infection (P ˃ 0.05). Animals sampled during the rainy season (n = 565; P = 82.2%, mean EPG = 154.8 ± 12.02) were mostly and heavily infected than those from the hot dry (n = 518; P = 74.2%; mean EPG = 97.7 ± 17.4) and the cold dry season (n = 392; P = 55.5%; mean EPG = 24.5 ± 19.5) (P ˂ 0.05). Females (n = 1027; P = 72.1%; mean EPG = 77.6 ± 17) were most infected than males (n = 448; P = 67.7%; mean EPG = 61.6 ± 19.5) (P ˂ 0.05). Animals that were treated, at most 3 months before sampling (n = 166; P = 61.5%; mean EPG = 41.7 ± 21.4), were less infected than those, which received this treatment after three months before sampling (n = 199; P = 74.8%; mean EPG = 89.1 ± 15.8) (P ˂ 0.05). Data from blood samples indicate that 6.5% of sheep was anaemic (PCV ≤ 19%), while 59.7% was noted anaemic regarding FAMACHA scores. PCV values varied significantly for FAMACHA scores, and the highest mean value was noted for score 1 (27.6) (P ˂ 0.05). The Cohen's kappa score between FAMACHA and PCV was 0.02. These findings suggest that strongyles infections are significantly associated with season, and heavier infections were noted during rainy season.
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Affiliation(s)
- L D Dahourou
- Institut des Sciences de l'Environnement et du Développement Rural (ISEDR), Université de Dédougou, Dédougou, BP 176, Burkina Faso.
- Laboratoire de Biologie et Santé animales (LaBioSA), Institut de l'Environnement et de Recherches Agricoles (INERA), 04 BP 8645, Ouagadougou, 04, Burkina Faso.
| | - A Konaté
- Laboratoire de Biologie et Santé animales (LaBioSA), Institut de l'Environnement et de Recherches Agricoles (INERA), 04 BP 8645, Ouagadougou, 04, Burkina Faso
| | - A S R Tapsoba
- Laboratoire de Biologie et Santé animales (LaBioSA), Institut de l'Environnement et de Recherches Agricoles (INERA), 04 BP 8645, Ouagadougou, 04, Burkina Faso
| | - A Dicko
- Laboratoire de Biologie et Santé animales (LaBioSA), Institut de l'Environnement et de Recherches Agricoles (INERA), 04 BP 8645, Ouagadougou, 04, Burkina Faso
| | - M Sanou
- Laboratoire de Biologie et Santé animales (LaBioSA), Institut de l'Environnement et de Recherches Agricoles (INERA), 04 BP 8645, Ouagadougou, 04, Burkina Faso
| | - H H Tamboura
- Laboratoire de Biologie et Santé animales (LaBioSA), Institut de l'Environnement et de Recherches Agricoles (INERA), 04 BP 8645, Ouagadougou, 04, Burkina Faso
| | - B Bayala
- Unité de Formation et de Recherches/Science de la Vie et de la Terre, Université de Ouagadougou, 03 BP 7021, Ouagadougou, 03, Burkina Faso
| | - I Salissou
- Institut National de Recherche Agronomique, BP 429, Niamey, Niger
| | - A Traoré
- Laboratoire de Biologie et Santé animales (LaBioSA), Institut de l'Environnement et de Recherches Agricoles (INERA), 04 BP 8645, Ouagadougou, 04, Burkina Faso
| | - L L Logan
- College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, 660 Raymond Stotzer Pkwy, College Station, TX, 77843, USA
| | - S Tembely
- Académie des Sciences du Mali, Baco-Djicoroni ACI Ouest, Rue 619 Porte, 104, Bamako, Mali
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de Wit M, Cairns M, Compaoré YD, Sagara I, Kuepfer I, Zongo I, Barry A, Diarra M, Tapily A, Coumare S, Thera I, Nikiema F, Yerbanga RS, Guissou RM, Tinto H, Dicko A, Chandramohan D, Greenwood B, Ouedraogo JB. Nutritional status in young children prior to the malaria transmission season in Burkina Faso and Mali, and its impact on the incidence of clinical malaria. Malar J 2021; 20:274. [PMID: 34158054 PMCID: PMC8220741 DOI: 10.1186/s12936-021-03802-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 06/07/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria and malnutrition remain major problems in Sahel countries, especially in young children. The direct effect of malnutrition on malaria remains poorly understood, and may have important implications for malaria control. In this study, nutritional status and the association between malnutrition and subsequent incidence of symptomatic malaria were examined in children in Burkina Faso and Mali who received either azithromycin or placebo, alongside seasonal malaria chemoprevention. METHODS Mid-upper arm circumference (MUAC) was measured in all 20,185 children who attended a screening visit prior to the malaria transmission season in 2015. Prior to the 2016 malaria season, weight, height and MUAC were measured among 4149 randomly selected children. Height-for-age, weight-for-age, weight-for-height, and MUAC-for-age were calculated as indicators of nutritional status. Malaria incidence was measured during the following rainy seasons. Multivariable random effects Poisson models were created for each nutritional indicator to study the effect of malnutrition on clinical malaria incidence for each country. RESULTS In both 2015 and 2016, nutritional status prior to the malaria season was poor. The most prevalent form of malnutrition in Burkina Faso was being underweight (30.5%; 95% CI 28.6-32.6), whereas in Mali stunting was most prevalent (27.5%; 95% CI 25.6-29.5). In 2016, clinical malaria incidence was 675 per 1000 person-years (95% CI 613-744) in Burkina Faso, and 1245 per 1000 person-years (95% CI 1152-1347) in Mali. There was some evidence that severe stunting was associated with lower incidence of malaria in Mali (RR 0.81; 95% CI 0.64-1.02; p = 0.08), but this association was not seen in Burkina Faso. Being moderately underweight tended to be associated with higher incidence of clinical malaria in Burkina Faso (RR 1.27; 95% CI 0.98-1.64; p = 0.07), while this was the case in Mali for moderate wasting (RR 1.27; 95% CI 0.98-1.64; p = 0.07). However, these associations were not observed in severely affected children, nor consistent between countries. MUAC-for-age was not associated with malaria risk. CONCLUSIONS Both malnutrition and malaria were common in the study areas, high despite high coverage of seasonal malaria chemoprevention and long-lasting insecticidal nets. However, no strong or consistent evidence was found for an association between any of the nutritional indicators and the subsequent incidence of clinical malaria.
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Affiliation(s)
- Mariken de Wit
- London School of Hygiene and Tropical Medicine, London, UK.
| | - Matthew Cairns
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - Issaka Sagara
- Malaria Research and Training Centre, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Irene Kuepfer
- London School of Hygiene and Tropical Medicine, London, UK
| | - Issaka Zongo
- Institut de Recherche en Sciences de La Santé, Bobo-Dioulasso, Burkina Faso
| | - Amadou Barry
- Malaria Research and Training Centre, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Modibo Diarra
- Malaria Research and Training Centre, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Amadou Tapily
- Malaria Research and Training Centre, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Samba Coumare
- Malaria Research and Training Centre, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Ismaila Thera
- Malaria Research and Training Centre, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Frederic Nikiema
- Institut de Recherche en Sciences de La Santé, Bobo-Dioulasso, Burkina Faso
| | - R Serge Yerbanga
- Institut de Recherche en Sciences de La Santé, Bobo-Dioulasso, Burkina Faso
| | | | - Halidou Tinto
- Institut de Recherche en Sciences de La Santé, Bobo-Dioulasso, Burkina Faso
| | - Alassane Dicko
- Malaria Research and Training Centre, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
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Sagara I, Woodford J, Kone M, Assadou MH, Katile A, Attaher O, Zeguime A, Doucoure M, Higbee E, Lane J, Doritchamou J, Zaidi I, Esposito D, Kwan J, Sadtler K, Dicko A, Duffy P. Rapidly increasing SARS-CoV-2 seroprevalence and limited clinical disease in three Malian communities: a prospective cohort study. medRxiv 2021:2021.04.26.21256016. [PMID: 33948607 PMCID: PMC8095226 DOI: 10.1101/2021.04.26.21256016] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Background The extent of SARS-CoV-2 exposure and transmission in Mali and the surrounding region is not well understood, although infection has been confirmed in nearly 14,000 symptomatic individuals and their contacts since the first case in March 2020. We aimed to estimate the cumulative incidence of SARS-CoV-2 in three Malian communities, and understand factors associated with infection. Methods Between 27 July 2020 and 29 January 2021, we collected blood samples along with demographic, social, medical and self-reported symptoms information from residents aged 6 months and older in three study communities at two study visits. SARS-CoV-2 antibodies were measured using a highly specific two-antigen ELISA optimized for use in Mali. We calculated cumulative adjusted seroprevalence for each site and evaluated factors associated with serostatus at each visit by univariate and multivariate analysis. Findings Overall, 94.8% (2533/2672) of participants completed both study visits. A total of 50.3% (1343/2672) of participants were male, and 31.3% (837/2672) were aged <10 years, 27.6% (737/2672) were aged 10-17 years, and 41.1% (1098/2572) were aged ≥18 years. The cumulative SARS-CoV-2 exposure rate was 58.5% (95% CI: 47.5 to 69.4). This varied between sites and was 73.4% (95% CI: 59.2 to 87.5) in the urban community of Sotuba, 53.2% (95% CI: 42.8 to 63.6) in the rural town of Bancoumana, and 37.1% (95% CI: 29.6 to 44.5) in the rural village of Donéguébougou. This equates to an infection rate of approximately 1% of the population every three days in the study communities between visits. Increased age and study site were associated with serostatus at both study visits. There was minimal difference in reported symptoms based on serostatus. Interpretation The true extent of SARS-CoV-2 exposure in Mali is greater than previously reported and now approaches hypothetical herd immunity in urban areas. The epidemiology of the pandemic in the region may be primarily subclinical and within background illness rates. In this setting, ongoing surveillance and augmentation of diagnostics to characterize locally circulating variants will be critical to implement effective mitigation strategies like vaccines. Funding This project was funded by the Intramural Research Program of the National Institute of Allergy and Infectious Diseases, National Institute of Biomedical Imaging and Bioengineering, and National Cancer Institute.
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Affiliation(s)
- Issaka Sagara
- Malaria Research and Teaching Center, University of Sciences, Techniques, and Technology of Bamako, Mali
| | - John Woodford
- Laboratory of Malaria Immunology and Vaccinology, National Institutes of Health, USA
| | - Mamady Kone
- Malaria Research and Teaching Center, University of Sciences, Techniques, and Technology of Bamako, Mali
| | - Mahamadoun Hamady Assadou
- Malaria Research and Teaching Center, University of Sciences, Techniques, and Technology of Bamako, Mali
| | - Abdoulaye Katile
- Malaria Research and Teaching Center, University of Sciences, Techniques, and Technology of Bamako, Mali
| | - Oumar Attaher
- Malaria Research and Teaching Center, University of Sciences, Techniques, and Technology of Bamako, Mali
| | - Amatigue Zeguime
- Malaria Research and Teaching Center, University of Sciences, Techniques, and Technology of Bamako, Mali
| | - M'Bouye Doucoure
- Malaria Research and Teaching Center, University of Sciences, Techniques, and Technology of Bamako, Mali
| | - Emily Higbee
- Laboratory of Malaria Immunology and Vaccinology, National Institutes of Health, USA
| | - Jacquelyn Lane
- Laboratory of Malaria Immunology and Vaccinology, National Institutes of Health, USA
| | - Justin Doritchamou
- Malaria Research and Teaching Center, University of Sciences, Techniques, and Technology of Bamako, Mali
- Laboratory of Malaria Immunology and Vaccinology, National Institutes of Health, USA
- Frederic National Laboratory for Cancer Research, National Insitutes of Health, National Institutes of Health, USA
- Laboratory of Clinical Immunology and Microbiology, National Institutes of Health, USA
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, USA
| | - Irfan Zaidi
- Malaria Research and Teaching Center, University of Sciences, Techniques, and Technology of Bamako, Mali
- Laboratory of Malaria Immunology and Vaccinology, National Institutes of Health, USA
- Frederic National Laboratory for Cancer Research, National Insitutes of Health, National Institutes of Health, USA
- Laboratory of Clinical Immunology and Microbiology, National Institutes of Health, USA
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, USA
| | - Dominic Esposito
- Frederic National Laboratory for Cancer Research, National Insitutes of Health, National Institutes of Health, USA
| | - Jennifer Kwan
- Laboratory of Clinical Immunology and Microbiology, National Institutes of Health, USA
| | - Kaitlyn Sadtler
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, USA
| | - Alassane Dicko
- Malaria Research and Teaching Center, University of Sciences, Techniques, and Technology of Bamako, Mali
| | - Patrick Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institutes of Health, USA
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Mahamar A, Andemel N, Swihart B, Sidibe Y, Gaoussou S, Barry A, Traore M, Attaher O, Dembele AB, Diarra BS, Keita S, Dicko A, Duffy PE, Fried M. Malaria infection is common and associated with perinatal mortality and preterm delivery despite widespread use of chemoprevention in Mali: an observational study 2010 to 2014. Clin Infect Dis 2021; 73:1355-1361. [PMID: 33846719 DOI: 10.1093/cid/ciab301] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND In malaria-endemic areas, pregnant women and especially first-time mothers are more susceptible to Plasmodium falciparum. Malaria diagnosis is often missed during pregnancy, since many women with placental malaria remain asymptomatic or have submicroscopic parasitemia, masking the association between malaria and pregnancy outcomes Severe maternal anemia and low birthweight deliveries are well-established sequelae, but few studies have confirmed the relationship between malaria infection and severe outcomes like perinatal mortality in high transmission zones. METHODS Pregnant women of any gestational age enrolled at antenatal clinic into a longitudinal cohort study in Ouelessebougou, Mali, an area of high seasonal malaria transmission. Follow-up visits included scheduled and unscheduled visits throughout pregnancy. Blood smear microscopy and PCR analysis were employed to detect both microscopic and submicroscopic infections, respectively. Intermittent preventative treatment in pregnancy with sulfadoxine-pyrimethamine (IPTp-SP) was documented and prompt treatment regardless of symptoms given upon malaria diagnosis. RESULTS Of the 1850 women followed through delivery, 72.6% of women received 2 or more IPTp-SP doses, 67.2% of women experienced at least one infection between enrollment up to and including delivery. Malaria infection increased the risks of stillbirth (adjusted-hazard ratio (aHR) 3.87, 95%CI 1.18-12.71) and preterm delivery (aHR 2.41, 95%CI 1.35-4.29) in primigravidae, and early neonatal death (death within 7 days) in secundigravidae and multigravidae (HR 6.30, 95%CI 1.41-28.15). CONCLUSIONS Malaria treatment after diagnosis, alongside IPTp-SP, is insufficient to prevent malaria-related stillbirth, early neonatal death and PTD. While IPTp-SP was beneficial in Mali during the study period, new tools are needed to improve pregnancy outcomes.
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Affiliation(s)
- Almahamoudou Mahamar
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako;, Bamako, Mali
| | - Naissem Andemel
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Bruce Swihart
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Maryland, USA
| | - Youssoufa Sidibe
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako;, Bamako, Mali
| | - Santara Gaoussou
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako;, Bamako, Mali
| | - Amadou Barry
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako;, Bamako, Mali
| | - Moussa Traore
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako;, Bamako, Mali
| | - Oumar Attaher
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako;, Bamako, Mali
| | - Adama B Dembele
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako;, Bamako, Mali
| | - Bacary S Diarra
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako;, Bamako, Mali
| | - Sekouba Keita
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako;, Bamako, Mali
| | - Alassane Dicko
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako;, Bamako, Mali
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
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Sepúlveda N, Grignard L, Curry J, Mahey L, Bastiaens GJH, Tiono AB, Okebe J, Coulibaly SA, Gonçalves BP, Affara M, Ouédraogo A, Bougouma EC, Sanou GS, Nébié I, Lanke K, Sirima SB, Dicko A, d’Alessandro U, Clark TG, Campino S, Chen I, Eziefula AC, Gosling R, Bousema T, Drakeley C. G6PD Polymorphisms and Hemolysis After Antimalarial Treatment With Low Single-Dose Primaquine: A Pooled Analysis of Six African Clinical Trials. Front Genet 2021; 12:645688. [PMID: 33897764 PMCID: PMC8062977 DOI: 10.3389/fgene.2021.645688] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 02/23/2021] [Indexed: 11/13/2022] Open
Abstract
Primaquine (PQ) is an antimalarial drug with the potential to reduce malaria transmission due to its capacity to clear mature Plasmodium falciparum gametocytes in the human host. However, the large-scale roll-out of PQ has to be counterbalanced by the additional risk of drug-induced hemolysis in individuals suffering from Glucose-6-phospate dehydrogenase (G6PD) deficiency, a genetic condition determined by polymorphisms on the X-linked G6PD gene. Most studies on G6PD deficiency and PQ-associated hemolysis focused on the G6PD A- variant, a combination of the two single nucleotide changes G202A (rs1050828) and A376G (rs1050829), although other polymorphisms may play a role. In this study, we tested the association of 20 G6PD single nucleotide polymorphisms (SNPs) with hemolysis measured seven days after low single dose of PQ given at the dose of 0.1 mg/kg to 0.75 mg/kg in 957 individuals from 6 previously published clinical trials investigating the safety and efficacy of this drug spanning five African countries. After adjusting for inter-study effects, age, gender, baseline hemoglobin level, PQ dose, and parasitemia at screening, our analysis showed putative association signals from the common G6PD mutation, A376G [-log10(p-value) = 2.44] and two less-known SNPs, rs2230037 [-log10(p-value] = 2.60), and rs28470352 [-log10(p-value) = 2.15]; A376G and rs2230037 were in very strong linkage disequilibrium with each other (R 2 = 0.978). However, when the effects of these SNPs were included in the same regression model, the subsequent associations were in the borderline of statistical significance. In conclusion, whilst a role for the A- variant is well established, we did not observe an important additional role for other G6PD polymorphisms in determining post-treatment hemolysis in individuals treated with low single-dose PQ.
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Affiliation(s)
- Nuno Sepúlveda
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- CEAUL – Centro de Estatística e Aplicações da Universidade de Lisboa, Lisbon, Portugal
| | - Lynn Grignard
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | - Guido J. H. Bastiaens
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Alfred B. Tiono
- Department of Public Health, Centre National de Recherche et de Formation sur le Paludisme & Institut National de Santé Publique, Ouagadougou, Burkina Faso
| | - Joseph Okebe
- Department of International Public Health, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Sam A. Coulibaly
- Department of Public Health, Centre National de Recherche et de Formation sur le Paludisme & Institut National de Santé Publique, Ouagadougou, Burkina Faso
| | - Bronner P. Gonçalves
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Muna Affara
- MRC Unit The Gambia at the London School of Hygiene & Tropical Medicine, Fajara, Gambia
| | - Alphonse Ouédraogo
- Department of Public Health, Centre National de Recherche et de Formation sur le Paludisme & Institut National de Santé Publique, Ouagadougou, Burkina Faso
| | - Edith C. Bougouma
- Department of Public Health, Centre National de Recherche et de Formation sur le Paludisme & Institut National de Santé Publique, Ouagadougou, Burkina Faso
| | - Guillaume S. Sanou
- Department of Public Health, Centre National de Recherche et de Formation sur le Paludisme & Institut National de Santé Publique, Ouagadougou, Burkina Faso
| | - Issa Nébié
- Department of Public Health, Centre National de Recherche et de Formation sur le Paludisme & Institut National de Santé Publique, Ouagadougou, Burkina Faso
| | - Kjerstin Lanke
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Sodiomon B. Sirima
- Department of Public Health, Centre National de Recherche et de Formation sur le Paludisme & Institut National de Santé Publique, Ouagadougou, Burkina Faso
| | - Alassane Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences, Techniques and Technology of Bamako, Bamako, Mali
| | - Umberto d’Alessandro
- MRC Unit The Gambia at the London School of Hygiene & Tropical Medicine, Fajara, Gambia
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Taane G. Clark
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Susana Campino
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Ingrid Chen
- Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, United States
| | - Alice C. Eziefula
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Global Health and Infection, Brighton and Sussex Medical School, University of Sussex, Brighton, United Kingdom
| | - Roly Gosling
- Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, United States
| | - Teun Bousema
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Chris Drakeley
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Sagara I, Woodford J, Dicko A, Zeguime A, Doucoure M, Kwan J, Zaidi I, Doritchamou J, Snow-Smith M, Alani N, Renn J, Kosik I, Holly J, Yewdell J, Esposito D, Sadtler K, Duffy P. SARS-CoV-2 seroassay optimization and performance in a population with high background reactivity in Mali. medRxiv 2021:2021.03.08.21252784. [PMID: 33758883 PMCID: PMC7987042 DOI: 10.1101/2021.03.08.21252784] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Serological tests are an indispensable tool to understand the epidemiology of the SARS-CoV-2 pandemic, particularly in areas where molecular diagnostics are limited. Poor assay performance may hinder the utility of these tests, including high rates of false-positivity previously reported in sub-Saharan Africa. From 312 Malian samples collected prior to 2020, we measured antibodies to the commonly tested SARS-CoV-2 antigens and four other betacoronaviruses by ELISA, and assessed functional cross-reactivity in a subset by SARS-CoV-2 pseudovirus neutralization assay. We then evaluated the performance of an ELISA developed in the US, using two-antigen SARS-CoV-2 spike protein and receptor-binding domain. To optimize test performance, we compared single and two-antigen approaches using existing assay cutoffs and population-specific cutoffs for Malian control samples (positive and negative). Background reactivity to SARS-CoV-2 antigens was common in pre-pandemic samples compared to US controls (43.4% (135/311) for spike protein, 22.8% (71/312) for RBD, and 33.9% (79/233) for nucleocapsid protein). SARS-CoV-2 reactivity correlated weakly with other betacoronavirus reactivity, varied between Malian communities, and increased with age. No pre-pandemic samples demonstrated functional activity. Regardless of the cutoffs applied, specificity improved using a two-antigen approach. Test performance was optimal using a two-antigen assay with population-specific cutoffs derived from ROC curve analysis [Sensitivity: 73.9% (51.6-89.8), Specificity: 99.4% (97.7-99.9)]. In the setting of high background reactivity, such as sub-Saharan Africa, SARS-CoV-2 serological assays need careful qualification is to characterize the epidemiology of disease, prevent unnecessary harm, and allocate resources for targeted control measures.
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Diawara H, Walker P, Cairns M, Steinhardt LC, Diawara F, Kamate B, Duval L, Sicuri E, Sagara I, Sadou A, Mihigo J, Eckert E, Dicko A, Conteh L. Cost-effectiveness of district-wide seasonal malaria chemoprevention when implemented through routine malaria control programme in Kita, Mali using fixed point distribution. Malar J 2021; 20:128. [PMID: 33663488 PMCID: PMC7934250 DOI: 10.1186/s12936-021-03653-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 02/16/2021] [Indexed: 11/10/2022] Open
Abstract
Background Seasonal malaria chemoprevention (SMC) is a strategy for malaria control recommended by the World Health Organization (WHO) since 2012 for Sahelian countries. The Mali National Malaria Control Programme adopted a plan for pilot implementation and nationwide scale-up by 2016. Given that SMC is a relatively new approach, there is an urgent need to assess the costs and cost effectiveness of SMC when implemented through the routine health system to inform decisions on resource allocation. Methods Cost data were collected from pilot implementation of SMC in Kita district, which targeted 77,497 children aged 3–59 months. Starting in August 2014, SMC was delivered by fixed point distribution in villages with the first dose observed each month. Treatment consisted of sulfadoxine-pyrimethamine and amodiaquine once a month for four consecutive months, or rounds. Economic and financial costs were collected from the provider perspective using an ingredients approach. Effectiveness estimates were based upon a published mathematical transmission model calibrated to local epidemiology, rainfall patterns and scale-up of interventions. Incremental cost effectiveness ratios were calculated for the cost per malaria episode averted, cost per disability adjusted life years (DALYs) averted, and cost per death averted. Results The total economic cost of the intervention in the district of Kita was US $357,494. Drug costs and personnel costs accounted for 34% and 31%, respectively. Incentives (payment other than salary for efforts beyond routine activities) accounted for 25% of total implementation costs. Average financial and economic unit costs per child per round were US $0.73 and US $0.86, respectively; total annual financial and economic costs per child receiving SMC were US $2.92 and US $3.43, respectively. Accounting for coverage, the economic cost per child fully adherent (receiving all four rounds) was US $6.38 and US $4.69, if weighted highly adherent, (receiving 3 or 4 rounds of SMC). When costs were combined with modelled effects, the economic cost per malaria episode averted in children was US $4.26 (uncertainty bound 2.83–7.17), US $144 (135–153) per DALY averted and US $ 14,503 (13,604–15,402) per death averted. Conclusions When implemented at fixed point distribution through the routine health system in Mali, SMC was highly cost-effective. As in previous SMC implementation studies, financial incentives were a large cost component.
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Affiliation(s)
- Halimatou Diawara
- Malaria Research & Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali.
| | - Patrick Walker
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
| | - Matt Cairns
- London School of Hygiene & Tropical Medicine, London, UK
| | - Laura C Steinhardt
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Mailstop H24-3, Atlanta, GA, 30329, USA
| | - Fatou Diawara
- Malaria Research & Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Beh Kamate
- Maternal and Child Survival Program, Save the Children, Bamako, Mali
| | - Laeticia Duval
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
| | - Elisa Sicuri
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
| | - Issaka Sagara
- Malaria Research & Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Aboubacar Sadou
- President's Malaria Initiative, US Agency for International Development, Kinshasa, Democratic Republic of the Congo
| | - Jules Mihigo
- President's Malaria Initiative, US Agency for International Development, Bamako, Mali
| | - Erin Eckert
- President's Malaria Initiative, USAID Bureau for Global Health, Office of Health, Infectious Diseases, and Nutrition, 2100 Crystal Drive, Arlington, VA, 22202, USA
| | - Alassane Dicko
- Malaria Research & Training Centre, Faculty of Pharmacy and Faculty of Medicine and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Lesong Conteh
- Department of Health Policy, London School of Economics and Political Science, Houghton Street, London, WC2A 2AE, UK
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50
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Mahamar A, Lanke K, Graumans W, Diawara H, Sanogo K, Diarra K, Niambele SM, Gosling R, Drakeley C, Chen I, Dicko A, Bousema T, Roh ME. Persistence of mRNA indicative of Plasmodium falciparum ring-stage parasites 42 days after artemisinin and non-artemisinin combination therapy in naturally infected Malians. Malar J 2021; 20:34. [PMID: 33422068 PMCID: PMC7797096 DOI: 10.1186/s12936-020-03576-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 12/31/2020] [Indexed: 11/10/2022] Open
Abstract
Background Malaria control in sub-Saharan Africa relies upon prompt case management with artemisinin-based combination therapy (ACT). Ring-stage parasite mRNA, measured by sbp1 quantitative reverse-transcriptase PCR (qRT-PCR), was previously reported to persist after ACT treatment and hypothesized to reflect temporary arrest of the growth of ring-stage parasites (dormancy) following exposure to artemisinins. Here, the persistence of ring-stage parasitaemia following ACT and non-ACT treatment was examined. Methods Samples were used from naturally infected Malian gametocyte carriers who received dihydroartemisinin–piperaquine (DP) or sulfadoxine–pyrimethamine (SP–AQ) with or without gametocytocidal drugs. Gametocytes and ring-stage parasites were quantified by qRT-PCR during 42 days of follow-up. Results At baseline, 89% (64/73) of participants had measurable ring-stage parasite mRNA. Following treatment, the proportion of ring-stage parasite-positive individuals and estimated densities declined for all four treatment groups. Ring-stage parasite prevalence and density was generally lower in arms that received DP compared to SP–AQ. This finding was most apparent days 1, 2, and 42 of follow-up (p < 0.01). Gametocytocidal drugs did not influence ring-stage parasite persistence. Ring-stage parasite density estimates on days 14 and 28 after initiation of treatment were higher among individuals who subsequently experienced recurrent parasitaemia compared to those who remained free of parasites until day 42 after initiation of treatment (pday 14 = 0.011 and pday 28 = 0.068). No association of ring-stage persistence with gametocyte carriage was observed. Conclusions The current findings of lower ring-stage persistence after ACT without an effect of gametocytocidal partner drugs affirms the use of sbp1 as ring-stage marker. Lower persistence of ring-stage mRNA after ACT treatment suggests the marker may not reflect dormant parasites whilst it was predictive of re-appearance of parasitaemia.
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Affiliation(s)
- Almahamoudou Mahamar
- Malaria Research and Training Centre, Faculty of Pharmacy, Medicine, and Dentistry, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Kjerstin Lanke
- Radboud Institute for Health Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 26-28, PO Box 9101, 6525GA, Nijmegen, The Netherlands
| | - Wouter Graumans
- Radboud Institute for Health Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 26-28, PO Box 9101, 6525GA, Nijmegen, The Netherlands
| | - Halimatou Diawara
- Malaria Research and Training Centre, Faculty of Pharmacy, Medicine, and Dentistry, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Koualy Sanogo
- Malaria Research and Training Centre, Faculty of Pharmacy, Medicine, and Dentistry, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Kalifa Diarra
- Malaria Research and Training Centre, Faculty of Pharmacy, Medicine, and Dentistry, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Sidi Mohamed Niambele
- Malaria Research and Training Centre, Faculty of Pharmacy, Medicine, and Dentistry, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Roly Gosling
- Global Health Group, Malaria Elimination Initiative, University of California, San Francisco, CA, USA
| | - Chris Drakeley
- Department of Infection & Immunity, London School of Hygiene & Tropical Medicine, London, UK
| | - Ingrid Chen
- Global Health Group, Malaria Elimination Initiative, University of California, San Francisco, CA, USA
| | - Alassane Dicko
- Malaria Research and Training Centre, Faculty of Pharmacy, Medicine, and Dentistry, University of Science, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Teun Bousema
- Radboud Institute for Health Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 26-28, PO Box 9101, 6525GA, Nijmegen, The Netherlands. .,Department of Infection & Immunity, London School of Hygiene & Tropical Medicine, London, UK.
| | - Michelle E Roh
- Global Health Group, Malaria Elimination Initiative, University of California, San Francisco, CA, USA
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