1
|
Huang S, Baker K, Ibinaiye T, Oresanya O, Nnaji C, Richardson S. Impact of seasonal malaria chemoprevention based on the number of medicines doses received on malaria burden among children aged 3-59 months in Nigeria: A propensity score-matched analysis. Trop Med Int Health 2024; 29:668-679. [PMID: 38842452 DOI: 10.1111/tmi.14019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Abstract
BACKGROUND Seasonal malaria chemoprevention using sulfadoxine-pyrimethamine plus amodiaquine (sulfadoxine-pyrimethamine plus amodiaquine on Day 1 and amodiaquine on both Day 2 and Day 3) is delivered to children aged 3-59 months in areas of highly season malaria transmission. While the overall population-level impact of seasonal malaria chemoprevention on malaria control has been documented in various countries and time periods, there is no clear evidence regarding seasonal malaria chemoprevention impact based on the number of medicine doses children receive in one cycle in routine programmatic conditions. METHODS Data were extracted from Nigeria's routinely collected seasonal malaria chemoprevention end-of-round coverage surveys (2021, 2022). We matched seasonal malaria chemoprevention-targeted children who received specific numbers of seasonal malaria chemoprevention medicines with those who did not receive any doses of seasonal malaria chemoprevention medicines (non-sulfadoxine-pyrimethamine plus amodiaquine) using multiple sets of propensity score matches. We performed multilevel logistic regression for each matched group to evaluate the association between the number of doses of seasonal malaria chemoprevention medicines and monthly confirmed malaria cases (caregiver-reported malaria infection diagnosed by rapid diagnostic test at a health facility following the penultimate cycle of seasonal malaria chemoprevention). RESULTS Among 21,621 SMC-targeted children, 9.7% received non-sulfadoxine-pyrimethamine plus amodiaquine, 0.5% received only Day 1 sulfadoxine-pyrimethamine plus amodiaquine, 1.0% received Day 1 sulfadoxine-pyrimethamine plus amodiaquine and either Day 2 amodiaquine or Day 3 amodiaquine (sulfadoxine-pyrimethamine plus amodiaquine + amodiaquine), and 88.8% received Day 1 sulfadoxine-pyrimethamine plus amodiaquine and both Day 2 and Day 3 amodiaquine (sulfadoxine-pyrimethamine plus amodiaquine + amodiaquine + amodiaquine). Children receiving only Day 1 sulfadoxine-pyrimethamine plus amodiaquine did not have significant lower odds of rapid diagnostic tests-confirmed malaria than those receiving non-sulfadoxine-pyrimethamine plus amodiaquine (OR 0.77, 0.42-1.42). However, children receiving sulfadoxine-pyrimethamine plus amodiaquine + amodiaquine had significantly lower odds of rapid diagnostic tests-confirmed malaria than those receiving non-sulfadoxine-pyrimethamine plus amodiaquine (OR 0.42, 95% CI 0.28-0.63). Similarly, children receiving sulfadoxine-pyrimethamine plus amodiaquine + amodiaquine + amodiaquine also had significantly lower odds of rapid diagnostic test-confirmed malaria than those receiving non-sulfadoxine-pyrimethamine plus amodiaquine (OR 0.54, 95% CI 0.47-0.62). CONCLUSION Adherence to at least one daily dose of amodiaquine administration following receipt of Day 1 sulfadoxine-pyrimethamine plus amodiaquine by eligible children is crucial to ensure the effectiveness of seasonal malaria chemoprevention. This demonstrates the importance of enhancing caregiver awareness regarding the importance of amodiaquine and identifying barriers toward amodiaquine administration at the community level.
Collapse
Affiliation(s)
- Sikai Huang
- Vanke School of Public Health, Tsinghua University, Beijing, China
| | - Kevin Baker
- Malaria Consortium UK, The Green House, London, UK
- Department of Global Public Health, Karolinska Institute, Stockholm, Sweden
| | | | | | - Chuks Nnaji
- Malaria Consortium UK, The Green House, London, UK
| | - Sol Richardson
- Vanke School of Public Health, Tsinghua University, Beijing, China
| |
Collapse
|
2
|
Oldenburg CE, Ouattara M, Bountogo M, Boudo V, Ouedraogo T, Compaoré G, Dah C, Zakane A, Coulibaly B, Bagagnan C, Hu H, O’Brien KS, Nyatigo F, Keenan JD, Doan T, Porco TC, Arnold BF, Lebas E, Sié A, Lietman TM. Mass Azithromycin Distribution to Prevent Child Mortality in Burkina Faso: The CHAT Randomized Clinical Trial. JAMA 2024; 331:482-490. [PMID: 38349371 PMCID: PMC10865159 DOI: 10.1001/jama.2023.27393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 12/14/2023] [Indexed: 02/15/2024]
Abstract
Importance Repeated mass distribution of azithromycin has been shown to reduce childhood mortality by 14% in sub-Saharan Africa. However, the estimated effect varied by location, suggesting that the intervention may not be effective in different geographical areas, time periods, or conditions. Objective To evaluate the efficacy of twice-yearly azithromycin to reduce mortality in children in the presence of seasonal malaria chemoprevention. Design, Setting, and Participants This cluster randomized placebo-controlled trial evaluating the efficacy of single-dose azithromycin for prevention of all-cause childhood mortality included 341 communities in the Nouna district in rural northwestern Burkina Faso. Participants were children aged 1 to 59 months living in the study communities. Interventions Communities were randomized in a 1:1 ratio to receive oral azithromycin or placebo distribution. Children aged 1 to 59 months were offered single-dose treatment twice yearly for 3 years (6 distributions) from August 2019 to February 2023. Main Outcomes and Measures The primary outcome was all-cause childhood mortality, measured during a twice-yearly enumerative census. Results A total of 34 399 children (mean [SD] age, 25.2 [18] months) in the azithromycin group and 33 847 children (mean [SD] age, 25.6 [18] months) in the placebo group were included. A mean (SD) of 90.1% (16.0%) of the censused children received the scheduled study drug in the azithromycin group and 89.8% (17.1%) received the scheduled study drug in the placebo group. In the azithromycin group, 498 deaths were recorded over 60 592 person-years (8.2 deaths/1000 person-years). In the placebo group, 588 deaths were recorded over 58 547 person-years (10.0 deaths/1000 person-years). The incidence rate ratio for mortality was 0.82 (95% CI, 0.67-1.02; P = .07) in the azithromycin group compared with the placebo group. The incidence rate ratio was 0.99 (95% CI, 0.72-1.36) in those aged 1 to 11 months, 0.92 (95% CI, 0.67-1.27) in those aged 12 to 23 months, and 0.73 (95% CI, 0.57-0.94) in those aged 24 to 59 months. Conclusions and Relevance Mortality in children (aged 1-59 months) was lower with biannual mass azithromycin distribution in a setting in which seasonal malaria chemoprevention was also being distributed, but the difference was not statistically significant. The study may have been underpowered to detect a clinically relevant difference. Trial Registration ClinicalTrials.gov Identifier: NCT03676764.
Collapse
Affiliation(s)
- Catherine E. Oldenburg
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Epidemiology & Biostatistics, University of California, San Francisco
- Department of Ophthalmology, University of California, San Francisco
- Institute for Global Health Sciences, University of California, San Francisco
| | | | | | | | | | | | - Clarisse Dah
- Centre de Recherche en Santé de Nouna, Burkina Faso
| | | | | | | | - Huiyu Hu
- Francis I. Proctor Foundation, University of California, San Francisco
| | - Kieran S. O’Brien
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Epidemiology & Biostatistics, University of California, San Francisco
| | - Fanice Nyatigo
- Francis I. Proctor Foundation, University of California, San Francisco
| | - Jeremy D. Keenan
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Ophthalmology, University of California, San Francisco
| | - Thuy Doan
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Ophthalmology, University of California, San Francisco
| | - Travis C. Porco
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Epidemiology & Biostatistics, University of California, San Francisco
- Department of Ophthalmology, University of California, San Francisco
| | - Benjamin F. Arnold
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Ophthalmology, University of California, San Francisco
| | - Elodie Lebas
- Francis I. Proctor Foundation, University of California, San Francisco
| | - Ali Sié
- Centre de Recherche en Santé de Nouna, Burkina Faso
| | - Thomas M. Lietman
- Francis I. Proctor Foundation, University of California, San Francisco
- Department of Epidemiology & Biostatistics, University of California, San Francisco
- Department of Ophthalmology, University of California, San Francisco
- Institute for Global Health Sciences, University of California, San Francisco
| |
Collapse
|
3
|
de Cola MA, Chestnutt EG, Richardson S, Baudry M, Nnaji C, Ibinaiye T, Moukénet A, Rotimi K, Sawadogo B, Okafor J, Compaoré CS, Oguoma C, Rassi C, Roca-Feltrer A. From efficacy to effectiveness: a comprehensive framework for monitoring, evaluating and optimizing seasonal malaria chemoprevention programmes. Malar J 2024; 23:39. [PMID: 38308288 PMCID: PMC10837904 DOI: 10.1186/s12936-024-04860-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 01/23/2024] [Indexed: 02/04/2024] Open
Abstract
BACKGROUND Seasonal Malaria Chemoprevention (SMC) is a highly effective intervention for preventing malaria, particularly in areas with highly seasonal transmission. Monitoring and evaluating (M&E) SMC programmes are complex due to the scale, time-sensitive delivery of the programme, and influence of external factors. This paper describes the process followed to develop a comprehensive M&E framework tailored specifically for the SMC context. METHODS The Framework was developed through a literature and programme review, and stakeholder dialogues across three implementing countries-Burkina Faso, Chad, and Nigeria. Expert consultation further refined the Framework through an iterative approach drawing upon data collected through the three sources. The Framework was designed using the Logical Framework Approach incorporating external factors and intentionally aligned with global malaria M&E standards. RESULTS An overall aim and seven programme objectives were developed measured by 70 indicators. The indicators also capture the causal links between the implementation and results of the programme. The Framework leverages the use of current data sources and existing mechanisms, ensuring efficient data use without requiring a significant increase in resources for overall programme optimization. It also promotes the use of data triangulation, and stratification for a more nuanced understanding of factors affecting programme performance and timely data informed decision-making. CONCLUSIONS The SMC M&E Framework presented here provides a standardized approach for programme implementers to enhance decision-making for optimal programme performance. This is an essential tool as the scope of SMC programmes expands to new geographies and target age groups.
Collapse
Affiliation(s)
- Monica Anna de Cola
- Malaria Consortium, 244-254 Cambridge Heath Rd, Cambridge Heath, London, E2 9DA, UK.
| | | | - Sol Richardson
- Vanke School of Public Health, Tsinghua University, Beijing, China
| | | | - Chuks Nnaji
- Malaria Consortium, 244-254 Cambridge Heath Rd, Cambridge Heath, London, E2 9DA, UK
| | | | | | | | | | | | | | | | - Christian Rassi
- Malaria Consortium, 244-254 Cambridge Heath Rd, Cambridge Heath, London, E2 9DA, UK
| | | |
Collapse
|
4
|
Thwing J, Williamson J, Cavros I, Gutman JR. Systematic Review and Meta-Analysis of Seasonal Malaria Chemoprevention. Am J Trop Med Hyg 2024; 110:20-31. [PMID: 38081050 PMCID: PMC10793029 DOI: 10.4269/ajtmh.23-0481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Accepted: 10/23/2023] [Indexed: 01/05/2024] Open
Abstract
Seasonal malaria chemoprevention (SMC) for children under 5 years of age for up to four monthly cycles during malaria transmission season was recommended by the WHO in 2012 and has been implemented in 13 countries in the Sahel, reaching more than 30 million children annually. Malaria control programs implementing SMC have asked the WHO to consider expanding the age range or number of monthly cycles. We conducted a systematic review and meta-analysis of SMC among children up to 15 years of age and up to six monthly cycles. Twelve randomized studies were included, with outcomes stratified by age (< 5/≥ 5 years), by three or four versus five or six cycles, and by drug where possible. Drug regimens included sulfadoxine-pyrimethamine + amodiaquine, amodiaquine-artesunate, and sulfadoxine-pyrimethamine + artesunate. Included studies were all conducted in Sahelian countries in which high-grade resistance to sulfadoxine-pyrimethamine was rare and in zones with parasite prevalence ranging from 1% to 79%. Seasonal malaria chemoprevention resulted in substantial reductions in uncomplicated malaria incidence measured during that transmission season (rate ratio: 0.27, 95% CI: 0.25-0.29 among children < 5 years; rate ratio: 0.27, 95% CI: 0.25-0.30 among children ≥ 5 years) and in the prevalence of malaria parasitemia measured within 4-6 weeks from the final SMC cycle (risk ratio: 0.38, 95% CI: 0.34-0.43 among children < 5 years; risk ratio: 0.23, 95% CI: 0.11-0.48 among children ≥ 5 years). In high-transmission zones, SMC resulted in a moderately reduced risk of any anemia (risk ratio: 0.77, 95% CI: 0.72-0.83 among children < 5 years; risk ratio: 0.70, 95% CI: 0.52-0.95 among children ≥ 5 years [one study]). Children < 10 years of age had a moderate reduction in severe malaria (risk ratio: 0.53, 95% CI: 0.37-0.76) but no evidence of a mortality reduction. The evidence suggests that in areas in which sulfadoxine-pyrimethamine and amodiaquine remained efficacious, SMC effectively reduced malaria disease burden among children both < 5 and ≥ 5 years old and that the number of cycles should be commensurate with the length of the transmission season, up to six cycles.
Collapse
Affiliation(s)
- Julie Thwing
- Malaria Branch, Center for Global Health, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia
| | - John Williamson
- Malaria Branch, Center for Global Health, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Irene Cavros
- U.S. President’s Malaria Initiative, Malaria Branch, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Julie R. Gutman
- Malaria Branch, Center for Global Health, U.S. Centers for Disease Control and Prevention, Atlanta, Georgia
| |
Collapse
|
5
|
Xu M, Hu YX, Lu SN, Idris MA, Zhou SD, Yang J, Feng XN, Huang YM, Xu X, Chen Y, Wang DQ. Seasonal malaria chemoprevention in Africa and China's upgraded role as a contributor: a scoping review. Infect Dis Poverty 2023; 12:63. [PMID: 37403183 DOI: 10.1186/s40249-023-01115-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 06/14/2023] [Indexed: 07/06/2023] Open
Abstract
BACKGROUND Children under five are the vulnerable population most at risk of being infected with Plasmodium parasites, especially in the Sahel region. Seasonal malaria chemoprevention (SMC) recommended by World Health Organization (WHO), has proven to be a highly effective intervention to prevent malaria. Given more deaths reported during the COVID-19 pandemic than in previous years due to the disruptions to essential medical services, it is, therefore, necessary to seek a more coordinated and integrated approach to increasing the pace, coverage and resilience of SMC. Towards this end, fully leverage the resources of major players in the global fight against malaria, such as China could accelerate the SMC process in Africa. METHODS We searched PubMed, MEDLINE, Web of Science, and Embase for research articles and the Institutional Repository for Information Sharing of WHO for reports on SMC. We used gap analysis to investigate the challenges and gaps of SMC since COVID-19. Through the above methods to explore China's prospective contribution to SMC. RESULTS A total of 68 research articles and reports were found. Through gap analysis, we found that despite the delays in the SMC campaign, 11.8 million children received SMC in 2020. However, there remained some challenges: (1) a shortage of fully covered monthly courses; (2) lack of adherence to the second and third doses of amodiaquine; (3) four courses of SMC are not sufficient to cover the entire malaria transmission season in areas where the peak transmission lasts longer; (4) additional interventions are needed to consolidate SMC efforts. China was certified malaria-free by WHO in 2021, and its experience and expertise in malaria elimination can be shared with high-burden countries. With the potential to join the multilateral cooperation in SMC, including the supply of quality-assured health commodities, know-how transfer and experience sharing, China is expected to contribute to the ongoing scale-up of SMC. CONCLUSIONS A combination of necessary preventive and curative activities may prove beneficial both for targeted populations and for health system strengthening in the long run. More actions are entailed to promote the partnership and China can be one of the main contributors with various roles.
Collapse
Affiliation(s)
- Ming Xu
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Yun-Xuan Hu
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Shen-Ning Lu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Centre for Tropical Diseases, National Center for International Research On Tropical Diseases, Shanghai, China
| | | | - Shu-Duo Zhou
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Jian Yang
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Xiang-Ning Feng
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Yang-Mu Huang
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Xian Xu
- Anhui Provincial Center for Disease Control and Prevention, Hefei, China
| | - Ying Chen
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China.
- Institute for Global Health and Development, Peking University, Beijing, China.
| | - Duo-Quan Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Centre for Tropical Diseases, National Center for International Research On Tropical Diseases, Shanghai, China.
- School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| |
Collapse
|
6
|
Sarfo JO, Amoadu M, Kordorwu PY, Adams AK, Gyan TB, Osman AG, Asiedu I, Ansah EW. Malaria amongst children under five in sub-Saharan Africa: a scoping review of prevalence, risk factors and preventive interventions. Eur J Med Res 2023; 28:80. [PMID: 36800986 PMCID: PMC9936673 DOI: 10.1186/s40001-023-01046-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 02/06/2023] [Indexed: 02/19/2023] Open
Abstract
INTRODUCTION Africa has a higher burden of malaria-related cases and deaths globally. Children under five accounted for over two-thirds of all malaria deaths in sub-Saharan Africa (SSA). This scoping review aims to map evidence of the prevalence, contextual factors and health education interventions of malaria amongst children under 5 years (UN5) in SSA. METHOD Four main databases (PubMed, Central, Dimensions and JSTOR) produced 27,841 records of literature. Additional searches in Google, Google Scholar and institutional repositories produced 37 records. Finally, 255 full-text records were further screened, and 100 records were used for this review. RESULTS Low or no formal education, poverty or low income and rural areas are risk factors for malaria amongst UN5. Evidence on age and malnutrition as risk factors for malaria in UN5 is inconsistent and inconclusive. Furthermore, the poor housing system in SSA and the unavailability of electricity in rural areas and unclean water make UN5 more susceptible to malaria. Health education and promotion interventions have significantly reduced the malaria burden on UN5 in SSA. CONCLUSION Well-planned and resourced health education and promotion interventions that focus on prevention, testing and treatment of malaria could reduce malaria burden amongst UN5 in SSA.
Collapse
Affiliation(s)
- Jacob Owusu Sarfo
- grid.413081.f0000 0001 2322 8567University of Cape Coast, Cape Coast, Ghana
| | | | - Peace Yaa Kordorwu
- grid.413081.f0000 0001 2322 8567University of Cape Coast, Cape Coast, Ghana
| | - Abdul Karim Adams
- grid.413081.f0000 0001 2322 8567University of Cape Coast, Cape Coast, Ghana
| | | | - Abdul-Ganiyu Osman
- grid.413081.f0000 0001 2322 8567University of Cape Coast, Cape Coast, Ghana
| | - Immanuel Asiedu
- grid.413081.f0000 0001 2322 8567University of Cape Coast, Cape Coast, Ghana
| | | |
Collapse
|
7
|
Cissoko M, Sagara I, Landier J, Guindo A, Sanogo V, Coulibaly OY, Dembélé P, Dieng S, Bationo CS, Diarra I, Magassa MH, Berthé I, Katilé A, Traoré D, Dessay N, Gaudart J. Sub-national tailoring of seasonal malaria chemoprevention in Mali based on malaria surveillance and rainfall data. Parasit Vectors 2022; 15:278. [PMID: 35927679 PMCID: PMC9351140 DOI: 10.1186/s13071-022-05379-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 06/28/2022] [Indexed: 11/16/2022] Open
Abstract
Background In malaria endemic countries, seasonal malaria chemoprevention (SMC) interventions are performed during the high malaria transmission in accordance with epidemiological surveillance data. In this study we propose a predictive approach for tailoring the timing and number of cycles of SMC in all health districts of Mali based on sub-national epidemiological surveillance and rainfall data. Our primary objective was to select the best of two approaches for predicting the onset of the high transmission season at the operational scale. Our secondary objective was to evaluate the number of malaria cases, hospitalisations and deaths in children under 5 years of age that would be prevented annually and the additional cost that would be incurred using the best approach. Methods For each of the 75 health districts of Mali over the study period (2014–2019), we determined (1) the onset of the rainy season period based on weekly rainfall data; (ii) the onset and duration of the high transmission season using change point analysis of weekly incidence data; and (iii) the lag between the onset of the rainy season and the onset of the high transmission. Two approaches for predicting the onset of the high transmission season in 2019 were evaluated. Results In the study period (2014–2019), the onset of the rainy season ranged from week (W) 17 (W17; April) to W34 (August). The onset of the high transmission season ranged from W25 (June) to W40 (September). The lag between these two events ranged from 5 to 12 weeks. The duration of the high transmission season ranged from 3 to 6 months. The best of the two approaches predicted the onset of the high transmission season in 2019 to be in June in two districts, in July in 46 districts, in August in 21 districts and in September in six districts. Using our proposed approach would prevent 43,819 cases, 1943 hospitalisations and 70 deaths in children under 5 years of age annually for a minimal additional cost. Our analysis shows that the number of cycles of SMC should be changed in 36 health districts. Conclusion Adapting the timing of SMC interventions using our proposed approach could improve the prevention of malaria cases and decrease hospitalisations and deaths. Future studies should be conducted to validate this approach. Graphical Abstract ![]()
Collapse
Affiliation(s)
- Mady Cissoko
- Malaria Research and Training Centre Ogobara K. Doumbo (MRTC-OKD), FMOS-FAPH, Mali-NIAID-ICER, Université Des Sciences, Des Techniques Et Des Technologies de Bamako, 1805, Bamako, Mali. .,INSERM, IRD, ISSPAM, UM1252, Aix-Marseille University, 13005, Marseille, France. .,Direction Régionale de la Santé de Tombouctou, 59, Tombouctou, Mali.
| | - Issaka Sagara
- Malaria Research and Training Centre Ogobara K. Doumbo (MRTC-OKD), FMOS-FAPH, Mali-NIAID-ICER, Université Des Sciences, Des Techniques Et Des Technologies de Bamako, 1805, Bamako, Mali.,INSERM, IRD, ISSPAM, UM1252, Aix-Marseille University, 13005, Marseille, France
| | - Jordi Landier
- INSERM, IRD, ISSPAM, UM1252, Aix-Marseille University, 13005, Marseille, France
| | - Abdoulaye Guindo
- Malaria Research and Training Centre Ogobara K. Doumbo (MRTC-OKD), FMOS-FAPH, Mali-NIAID-ICER, Université Des Sciences, Des Techniques Et Des Technologies de Bamako, 1805, Bamako, Mali.,INSERM, IRD, ISSPAM, UM1252, Aix-Marseille University, 13005, Marseille, France
| | - Vincent Sanogo
- Programme National de Lutte contre le Paludisme (PNLP Mali), 233, Bamako, Mali
| | - Oumou Yacouba Coulibaly
- Direction Générale de la Santé et Hygiène Publique, Sous-Direction Lutte Contre la Maladie (DGSHP-SDLM), 233, Bamako, Mali
| | - Pascal Dembélé
- Programme National de Lutte contre le Paludisme (PNLP Mali), 233, Bamako, Mali
| | - Sokhna Dieng
- INSERM, IRD, ISSPAM, UM1252, Aix-Marseille University, 13005, Marseille, France
| | | | - Issa Diarra
- Malaria Research and Training Centre Ogobara K. Doumbo (MRTC-OKD), FMOS-FAPH, Mali-NIAID-ICER, Université Des Sciences, Des Techniques Et Des Technologies de Bamako, 1805, Bamako, Mali
| | - Mahamadou H Magassa
- Programme National de Lutte contre le Paludisme (PNLP Mali), 233, Bamako, Mali
| | - Ibrahima Berthé
- Malaria Research and Training Centre Ogobara K. Doumbo (MRTC-OKD), FMOS-FAPH, Mali-NIAID-ICER, Université Des Sciences, Des Techniques Et Des Technologies de Bamako, 1805, Bamako, Mali
| | - Abdoulaye Katilé
- Malaria Research and Training Centre Ogobara K. Doumbo (MRTC-OKD), FMOS-FAPH, Mali-NIAID-ICER, Université Des Sciences, Des Techniques Et Des Technologies de Bamako, 1805, Bamako, Mali.,INSERM, IRD, ISSPAM, UM1252, Aix-Marseille University, 13005, Marseille, France
| | - Diahara Traoré
- Programme National de Lutte contre le Paludisme (PNLP Mali), 233, Bamako, Mali
| | - Nadine Dessay
- ESPACE-DEV, UMR228, IRD/UM/UR/UG/UA, Institut de Recherche Pour le Développement (IRD) France, 34093, Montpellier, France
| | - Jean Gaudart
- Malaria Research and Training Centre Ogobara K. Doumbo (MRTC-OKD), FMOS-FAPH, Mali-NIAID-ICER, Université Des Sciences, Des Techniques Et Des Technologies de Bamako, 1805, Bamako, Mali.,APHM, INSERM, SESSTIM, ISSPAM, Hop Timone, BioSTIC, Biostatistic & ICT, Aix-Marseille University, 13005, Marseille, France
| |
Collapse
|
8
|
Adjei MR, Kubio C, Buamah M, Sarfo A, Suuri T, Ibrahim S, Sadiq A, Abubakari II, Baafi JV. Effectiveness of seasonal malaria chemoprevention in reducing under-five malaria morbidity and mortality in the Savannah Region, Ghana. Ghana Med J 2022; 56:64-70. [PMID: 37449257 PMCID: PMC10336463 DOI: 10.4314/gmj.v56i2.2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/29/2023] Open
Abstract
OBJECTIVE To assess the effectiveness of seasonal malaria chemoprevention (SMC) in reducing under-five malaria morbidity and mortality. DESIGN Under-five malaria data for confirmed episodes, deaths, and number of children dosed per cycle of SMC campaign were extracted from the District Health Information Management System (DHIMS-2) for 2018-2019. Data verification was done to compare extracted data with the source for completeness and consistency. Association between SMC and the main outcome variables (malaria cases and mortality) was computed from 2X2 tables and reported as rate ratios at a 95% confidence level. SETTING All seven (7) districts in Savannah Region, Ghana. PARTICIPANTS Children under five years. INTERVENTION Sulphadoxine-Pyrimethamine and Amodiaquine (SPAQ) prophylaxis given monthly, four times, durng the rainy season (July to October). MAIN OUTCOME MEASURES SMC coverage per cycle and under-five malaria morbidity and mortality ratios. RESULTS Over 370,000 dose packs of SPAQ were administered with an average cycle coverage of 93%. There was approximately 17% (p<0.01) and 67% (p=0.047) reduction in malaria-related morbidity and mortality, respectively, in the implementation year compared with the baseline. This translated into nearly 9,300 episodes of all forms of malaria and nine malaria-attributable deaths averted by the intervention. CONCLUSION SMC (combined with existing control measures) wields prospects of accelerating the regional/national malaria elimination efforts if the implementation is optimised. Expansion of the intervention to other high-prevalence regions with seasonal variation in disease burden may be worthwhile. FUNDING None declared.
Collapse
Affiliation(s)
- Michael R Adjei
- Regional Health Directorate, Ghana Health Service, Damongo, Savannah Region, Ghana
| | - Chrysantus Kubio
- Regional Health Directorate, Ghana Health Service, Damongo, Savannah Region, Ghana
| | - Marcel Buamah
- Regional Health Directorate, Ghana Health Service, Damongo, Savannah Region, Ghana
| | - Adjei Sarfo
- Regional Health Directorate, Ghana Health Service, Damongo, Savannah Region, Ghana
| | - Thomas Suuri
- Regional Health Directorate, Ghana Health Service, Damongo, Savannah Region, Ghana
| | - Saeed Ibrahim
- Regional Health Directorate, Ghana Health Service, Damongo, Savannah Region, Ghana
| | - Abubakari Sadiq
- Regional Health Directorate, Ghana Health Service, Damongo, Savannah Region, Ghana
| | | | - Janet V Baafi
- Sunyani West District Health Directorate, Ghana Health Service, Fiapre, Bono Region, Ghana
| |
Collapse
|
9
|
Krezanoski PJ, Roh ME, Rek J, Nankabirwa JI, Arinaitwe E, Staedke SG, Nayiga S, Hsiang MS, Smith D, Kamya M, Dorsey G. Marked reduction in antibiotic usage following intensive malaria control in a cohort of Ugandan children. BMC Med 2021; 19:294. [PMID: 34844601 PMCID: PMC8630830 DOI: 10.1186/s12916-021-02167-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 10/21/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Intensive malaria control may have additional benefits beyond reducing the incidence of symptomatic malaria. We compared antibiotic treatment of children before and after the implementation of highly effective malaria control interventions in Tororo, a historically high transmission area of Uganda. METHODS Two successive cohorts of children, aged 0.5 to 10 years, were followed from September 2011 to October 2019 in a dedicated study clinic. Universal distribution of long-lasting insecticidal nets was conducted in 2013 and 2017. Sustained indoor residual spraying of insecticide (IRS) was initiated in December 2014. Generalized linear mixed-effects models were used to compare the incidence of antimalarial and antibiotic treatments before and after vector control measures were implemented. RESULTS Comparing the period prior to the implementation of IRS to the period after IRS had been sustained for 4-5 years, the adjusted incidence of malaria treatments decreased from 2.68 to 0.05 per person-year (incidence rate ratio [IRR] = 0.02, 95% CI 0.01-0.03, p < 0.001), and the adjusted incidence of antibiotic treatments decreased from 4.14 to 1.26 per person-year (IRR = 0.30, 95% CI 0.27-0.34, p < 0.001). The reduction in antibiotic usage was primarily associated with fewer episodes of symptomatic malaria and fewer episodes of fever with sub-microscopic parasitemia, both of which were frequently treated with antibiotics. CONCLUSIONS In a historically high transmission setting, the implementation of highly effective vector control interventions was followed by a marked reduction in antibiotic treatment of children. This added benefit of malaria control could have important implications for antibiotic prescribing practices, efforts to curtail antimicrobial resistance, and health system costs.
Collapse
Affiliation(s)
- Paul J Krezanoski
- University of California, 1001 Potrero Avenue, San Francisco, CA, 94118, USA.
| | - Michelle E Roh
- University of California, 1001 Potrero Avenue, San Francisco, CA, 94118, USA
| | - John Rek
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Joaniter I Nankabirwa
- Infectious Diseases Research Collaboration, Kampala, Uganda
- Makerere University College of Health Sciences, Kampala, Uganda
| | | | | | - Susan Nayiga
- Infectious Diseases Research Collaboration, Kampala, Uganda
- London School of Hygiene and Tropical Medicine, London, UK
| | - Michelle S Hsiang
- University of California, 1001 Potrero Avenue, San Francisco, CA, 94118, USA
| | | | - Moses Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda
- Makerere University College of Health Sciences, Kampala, Uganda
| | - Grant Dorsey
- University of California, 1001 Potrero Avenue, San Francisco, CA, 94118, USA
| |
Collapse
|
10
|
Mwakingwe-Omari A, Healy SA, Lane J, Cook DM, Kalhori S, Wyatt C, Kolluri A, Marte-Salcedo O, Imeru A, Nason M, Ding LK, Decederfelt H, Duan J, Neal J, Raiten J, Lee G, Hume JCC, Jeon JE, Ikpeama I, Kc N, Chakravarty S, Murshedkar T, Church LWP, Manoj A, Gunasekera A, Anderson C, Murphy SC, March S, Bhatia SN, James ER, Billingsley PF, Sim BKL, Richie TL, Zaidi I, Hoffman SL, Duffy PE. Two chemoattenuated PfSPZ malaria vaccines induce sterile hepatic immunity. Nature 2021; 595:289-294. [PMID: 34194041 PMCID: PMC11127244 DOI: 10.1038/s41586-021-03684-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 06/01/2021] [Indexed: 02/06/2023]
Abstract
The global decline in malaria has stalled1, emphasizing the need for vaccines that induce durable sterilizing immunity. Here we optimized regimens for chemoprophylaxis vaccination (CVac), for which aseptic, purified, cryopreserved, infectious Plasmodium falciparum sporozoites (PfSPZ) were inoculated under prophylactic cover with pyrimethamine (PYR) (Sanaria PfSPZ-CVac(PYR)) or chloroquine (CQ) (PfSPZ-CVac(CQ))-which kill liver-stage and blood-stage parasites, respectively-and we assessed vaccine efficacy against homologous (that is, the same strain as the vaccine) and heterologous (a different strain) controlled human malaria infection (CHMI) three months after immunization ( https://clinicaltrials.gov/ , NCT02511054 and NCT03083847). We report that a fourfold increase in the dose of PfSPZ-CVac(PYR) from 5.12 × 104 to 2 × 105 PfSPZs transformed a minimal vaccine efficacy (low dose, two out of nine (22.2%) participants protected against homologous CHMI), to a high-level vaccine efficacy with seven out of eight (87.5%) individuals protected against homologous and seven out of nine (77.8%) protected against heterologous CHMI. Increased protection was associated with Vδ2 γδ T cell and antibody responses. At the higher dose, PfSPZ-CVac(CQ) protected six out of six (100%) participants against heterologous CHMI three months after immunization. All homologous (four out of four) and heterologous (eight out of eight) infectivity control participants showed parasitaemia. PfSPZ-CVac(CQ) and PfSPZ-CVac(PYR) induced a durable, sterile vaccine efficacy against a heterologous South American strain of P. falciparum, which has a genome and predicted CD8 T cell immunome that differs more strongly from the African vaccine strain than other analysed African P. falciparum strains.
Collapse
Affiliation(s)
- Agnes Mwakingwe-Omari
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
- Center for Vaccine Research, GlaxoSmithKline, Rockville, MD, USA
| | - Sara A Healy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jacquelyn Lane
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - David M Cook
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Sahand Kalhori
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Charles Wyatt
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Aarti Kolluri
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Omely Marte-Salcedo
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Alemush Imeru
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Martha Nason
- Biostatistical Research Branch, National Institute of Allergy and Infectious Diseases, Rockville, MD, USA
| | - Lei K Ding
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Hope Decederfelt
- Clinical Center Pharmacy Department, National Institutes of Health, Bethesda, MD, USA
| | - Junhui Duan
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jillian Neal
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jacob Raiten
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Grace Lee
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jen C C Hume
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jihyun E Jeon
- Clinical Center Pharmacy Department, National Institutes of Health, Bethesda, MD, USA
| | - Ijeoma Ikpeama
- Department of Laboratory Medicine, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - Natasha Kc
- Sanaria, Rockville, MD, USA
- Protein Potential, Rockville, MD, USA
| | | | | | | | | | | | - Charles Anderson
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Sean C Murphy
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
- Department of Microbiology, University of Washington, Seattle, WA, USA
- Seattle Malaria Clinical Trials Center, Fred Hutch Cancer Research Center, Seattle, WA, USA
- Center for Emerging and Re-emerging Infectious Diseases, University of Washington, Seattle, WA, USA
| | - Sandra March
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sangeeta N Bhatia
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Cambridge, MA, USA
- Broad Institute, Cambridge, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
- Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | | | | | - B Kim Lee Sim
- Sanaria, Rockville, MD, USA
- Protein Potential, Rockville, MD, USA
| | | | - Irfan Zaidi
- 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.
| |
Collapse
|
11
|
Amimo F, Lambert B, Magit A, Sacarlal J, Hashizume M, Shibuya K. Plasmodium falciparum resistance to sulfadoxine-pyrimethamine in Africa: a systematic analysis of national trends. BMJ Glob Health 2021; 5:bmjgh-2020-003217. [PMID: 33214174 PMCID: PMC7678238 DOI: 10.1136/bmjgh-2020-003217] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/13/2020] [Accepted: 09/08/2020] [Indexed: 12/02/2022] Open
Abstract
Introduction The rising burden of drug resistance is a major challenge to the global fight against malaria. We estimated national Plasmodium falciparum resistance to sulfadoxine-pyrimethamine (SP) across Africa, from 2000 to 2020. Methods We assembled molecular, clinical and endemicity data covering malaria-endemic African countries up to December 2018. Subsequently, we reconstructed georeferenced patient data, using pfdhps540E and pfdhps581G to measure mid-level and high-level SP resistance. Gaussian process regression was applied to model spatiotemporal standardised prevalence. Results In eastern Africa, mid-level SP resistance increased by 64.0% (95% uncertainty interval, 30.7%–69.8%) in Tanzania, 55.4% (31.3%–65.2%) in Sudan, 45.7% (16.8%–54.3%) in Mozambique, 29.7% (10.0%–45.2%) in Kenya and 8.7% (1.4%–36.8%) in Malawi from 2000 to 2010. This was followed by a steady decline of 76.0% (39.6%–92.6%) in Sudan, 65.7% (25.5%–85.6%) in Kenya and 17.4% (2.6%–37.5%) in Tanzania from 2010 to 2020. In central Africa, the levels increased by 28.9% (7.2%–62.5%) in Equatorial Guinea and 85.3% (54.0%–95.9%) in the Congo from 2000 to 2020, while in the other countries remained largely unchanged. In western Africa, the levels have remained low from 2000 to 2020, except for Nigeria, with a reduction of 14.4% (0.7%–67.5%) and Mali, with an increase of 7.0% (0.8%–25.6%). High-level SP resistance increased by 5.5% (1.0%–20.0%) in Malawi, 4.7% (0.5%–25.4%) in Kenya and 2.0% (0.1%–39.2%) in Tanzania, from 2000 to 2020. Conclusion Under the WHO protocols, SP is no longer effective for intermittent preventive treatment in pregnancy and infancy in most of eastern Africa and parts of central Africa. Strengthening health systems capacity to monitor drug resistance at subnational levels across the endemicity spectrum is critical to achieve the global target to end the epidemic.
Collapse
Affiliation(s)
- Floriano Amimo
- Department of Global Health Policy, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan .,Faculty of Medicine, Eduardo Mondlane University, Maputo, Mozambique
| | - Ben Lambert
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London, UK
| | - Anthony Magit
- Human Research Protection Program, University of California San Diego School of Medicine, University of California System, San Diego, California, USA
| | - Jahit Sacarlal
- Faculty of Medicine, Eduardo Mondlane University, Maputo, Mozambique
| | - Masahiro Hashizume
- Department of Global Health Policy, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Kenji Shibuya
- Department of Global Health Policy, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.,Institute for Population Health, King's College London, London, UK
| |
Collapse
|
12
|
Audibert C, Tchouatieu AM. Perception of Malaria Chemoprevention Interventions in Infants and Children in Eight Sub-Saharan African Countries: An End User Perspective Study. Trop Med Infect Dis 2021; 6:tropicalmed6020075. [PMID: 34064620 PMCID: PMC8163176 DOI: 10.3390/tropicalmed6020075] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 05/03/2021] [Accepted: 05/06/2021] [Indexed: 11/16/2022] Open
Abstract
Preventive chemotherapy interventions have been identified as key tools for malaria prevention and control. Although a large number of publications have reported on the efficacy and safety profile of these interventions, little literature exists on end-user experience. The objective of this study was to provide insights on the perceptions and attitudes towards seasonal malaria chemoprevention (SMC) and intermittent preventive treatment of infants (IPTi) to identify drivers of and barriers to acceptance. A total of 179 in-depth qualitative interviews were conducted with community health workers (CHWs), health center managers, parents of children receiving chemoprevention, and national decision makers across eight countries in sub-Saharan Africa. The transcribed verbatim responses were coded and analyzed using a thematic approach. Findings indicate that, although SMC is largely accepted by end users, coverage remained below 100%. The main causes mentioned were children's absenteeism, children being sick, parents' reluctance, and lack of staff. Regarding IPTi, results from participants based in Sierra Leone showed that the intervention was generally accepted and perceived as efficacious. The main challenges were access to water, crushing the tablets, and high staff turnover. SMC and IPTi are perceived as valuable interventions. Our study identified the key elements that need to be considered to facilitate the expansion of these two interventions to different geographies or age groups.
Collapse
|
13
|
Coulibaly D, Guindo B, Niangaly A, Maiga F, Konate S, Kodio A, Diallo A, Antar ATM, Kone AK, Traore K, Travassos MA, Sagara I, Doumbo OK, Thera MA. A Decline and Age Shift in Malaria Incidence in Rural Mali following Implementation of Seasonal Malaria Chemoprevention and Indoor Residual Spraying. Am J Trop Med Hyg 2021; 104:1342-1347. [PMID: 33646974 PMCID: PMC8045648 DOI: 10.4269/ajtmh.20-0622] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 12/16/2020] [Indexed: 11/07/2022] Open
Abstract
Many African countries have reported declines in malaria incidence, attributed to the implementation of control strategies. In Mali, artemisinin-based combination therapy (ACT) was introduced in 2004, and long-lasting insecticide-treated nets (LLINs) have been partially distributed free of charge since 2007. In the Malian town of Bandiagara, a study conducted from 2009 to 2013 showed a stable incidence of malaria compared with 1999, despite the implementation of ACTs and LLINs. Since 2016, seasonal malaria chemoprevention has been scaled up across the country. In addition to these strategies, the population of Bandiagara benefited from indoor residual spray implementation in 2017 and 2018 and continued universal bed net coverage. This study aimed to measure the incidence of malaria in Bandiagara, given this recent scaling up of control strategies. A cohort of 300 children aged 6 months to 15 years was followed up from October 2017 to December 2018. We performed monthly cross-sectional surveys to measure anemia and the prevalence of malaria infection by microscopy. The overall incidence of symptomatic malaria was 0.5 episodes/person-year. Malaria incidence in children up to 5 years old significantly declined since 2012 and since 1999 (incidence rate ratio estimates: 6.7 [95% CI: 4.2-11.4] and 13.5 [95% CI: 8.4-22.7]), respectively. The average prevalence of malaria parasitemia was 6.7%. Malaria incidence was higher in children older than 5 years than in those younger than 5 years, highlighting the need to extend malaria control efforts to these older children.
Collapse
Affiliation(s)
- Drissa Coulibaly
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Boureima Guindo
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Amadou Niangaly
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Fayçal Maiga
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Salimata Konate
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Aly Kodio
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Astou Diallo
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Abdou Tahirou Mohamed Antar
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Abdoulaye K Kone
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Karim Traore
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Mark A Travassos
- 2Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland
| | - Issaka Sagara
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Ogobara K Doumbo
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Mahamadou A Thera
- 1Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Malaria Research and Training Center, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| |
Collapse
|
14
|
Affiliation(s)
- Geoffrey Guenther
- Department of Pediatrics, Children's National Hospital, Washington, DC, USA
| | - Daniel Muller
- The George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Dominic Moyo
- Department of Paediatric and Child Health, University of Malawi College of Medicine, Blantyre, Malawi
| | - Douglas Postels
- Department of Pediatric Neurology, George Washington University/ Children's National Medical Center; Washington DC, USA; Blantyre Malaria Project; Blantyre, Malawi, Street Address: Department of Neurology; 111 Michigan Avenue NW; Washington DC; 20010; USA
| |
Collapse
|
15
|
Near-term climate change impacts on sub-national malaria transmission. Sci Rep 2021; 11:751. [PMID: 33436862 PMCID: PMC7803742 DOI: 10.1038/s41598-020-80432-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 12/17/2020] [Indexed: 01/29/2023] Open
Abstract
The role of climate change on global malaria is often highlighted in World Health Organisation reports. We modelled a Zambian socio-environmental dataset from 2000 to 2016, against malaria trends and investigated the relationship of near-term environmental change with malaria incidence using Bayesian spatio-temporal, and negative binomial mixed regression models. We introduced the diurnal temperature range (DTR) as an alternative environmental measure to the widely used mean temperature. We found substantial sub-national near-term variations and significant associations with malaria incidence-trends. Significant spatio-temporal shifts in DTR/environmental predictors influenced malaria incidence-rates, even in areas with declining trends. We highlight the impact of seasonally sensitive DTR, especially in the first two quarters of the year and demonstrate how substantial investment in intervention programmes is negatively impacted by near-term climate change, most notably since 2010. We argue for targeted seasonally-sensitive malaria chemoprevention programmes.
Collapse
|
16
|
Maiga H, Gaudart J, Sagara I, Diarra M, Bamadio A, Djimde M, Coumare S, Sangare B, Dicko Y, Tembely A, Traore D, Dicko A, Lasry E, Doumbo O, Djimde AA. Two-Year Scale-Up of Seasonal Malaria Chemoprevention Reduced Malaria Morbidity among Children in the Health District of Koutiala, Mali. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E6639. [PMID: 32932990 PMCID: PMC7558455 DOI: 10.3390/ijerph17186639] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/03/2020] [Accepted: 09/05/2020] [Indexed: 11/17/2022]
Abstract
BACKGROUND Previous controlled studies demonstrated seasonal malaria chemoprevention (SMC) reduces malaria morbidity by >80% in children aged 3-59 months. Here, we assessed malaria morbidity after large-scale SMC implementation during a pilot campaign in the health district of Koutiala, Mali. METHODS Starting in August 2012, children received three rounds of SMC with sulfadoxine-pyrimethamine (SP) and amodiaquine (AQ). From July 2013 onward, children received four rounds of SMC. Prevalence of malaria infection, clinical malaria and anemia were assessed during two cross-sectional surveys conducted in August 2012 and June 2014. Investigations involved 20 randomly selected clusters in 2012 against 10 clusters in 2014. RESULTS Overall, 662 children were included in 2012, and 670 in 2014. Children in 2014 versus those surveyed in 2012 showed reduced proportions of malaria infection (12.4% in 2014 versus 28.7% in 2012 (p = 0.001)), clinical malaria (0.3% versus 4.2%, respectively (p < 0.001)), and anemia (50.1% versus 67.4%, respectively (p = 0.001)). A propensity score approach that accounts for environmental differences showed that SMC conveyed a significant protective effect against malaria infection (IR = 0.01, 95% CI (0.0001; 0.09), clinical malaria (OR = 0.25, 95% CI (0.06; 0.85)), and hemoglobin concentration (β = 1.3, 95% CI (0.69; 1.96)) in 2012 and 2014, respectively. CONCLUSION SMC significantly reduced frequency of malaria infection, clinical malaria and anemia two years after SMC scale-up in Koutiala.
Collapse
Affiliation(s)
- Hamma Maiga
- Institut National de Santé Publique, Bamako BP: 1771, Mali;
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| | - Jean Gaudart
- Aix Marseille Univ, APHM, IRD, INSERM, UMR1252 SESSTIM Sciences Economiques & Sociales de la Santé & Traitement de l’Information Médicale, Hop Timone, BioSTIC, Biostatistic & ICT, 13385 Marseille, France;
| | - Issaka Sagara
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
- Aix Marseille Univ, APHM, IRD, INSERM, UMR1252 SESSTIM Sciences Economiques & Sociales de la Santé & Traitement de l’Information Médicale, Hop Timone, BioSTIC, Biostatistic & ICT, 13385 Marseille, France;
| | - Modibo Diarra
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| | - Amadou Bamadio
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| | - Moussa Djimde
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| | - Samba Coumare
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| | - Boubou Sangare
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| | - Yeyia Dicko
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| | - Aly Tembely
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| | - Djibril Traore
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| | - Alassane Dicko
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| | - Estrella Lasry
- Médecins Sans Frontières (MSF), New York, NY 10006, USA;
| | - Ogobara Doumbo
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
- Aix Marseille Univ, APHM, IRD, INSERM, UMR1252 SESSTIM Sciences Economiques & Sociales de la Santé & Traitement de l’Information Médicale, Hop Timone, BioSTIC, Biostatistic & ICT, 13385 Marseille, France;
| | - Abdoulaye A. Djimde
- Malaria Research and Training Center, Department of Epidemiology of Parasitic Diseases, Faculty of Medicine and Dentistry, Faculty of Pharmacy, University of Sciences, Techniques and Technologies of Bamako, Bamako BP: 1805, Mali; (I.S.); (M.D.); (A.B.); (M.D.); (S.C.); (B.S.); (Y.D.); (A.T.); (D.T.); (A.D.); (O.D.)
| |
Collapse
|
17
|
Cairns ME, Sagara I, Zongo I, Kuepfer I, Thera I, Nikiema F, Diarra M, Yerbanga SR, Barry A, Tapily A, Coumare S, Milligan P, Tinto H, Ouédraogo JB, Chandramohan D, Greenwood B, Djimde A, Dicko A. Evaluation of seasonal malaria chemoprevention in two areas of intense seasonal malaria transmission: Secondary analysis of a household-randomised, placebo-controlled trial in Houndé District, Burkina Faso and Bougouni District, Mali. PLoS Med 2020; 17:e1003214. [PMID: 32822362 PMCID: PMC7442230 DOI: 10.1371/journal.pmed.1003214] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 07/31/2020] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Seasonal malaria chemoprevention (SMC) is now widely deployed in the Sahel, including several countries that are major contributors to the global burden of malaria. Consequently, it is important to understand whether SMC continues to provide a high level of protection and how SMC might be improved. SMC was evaluated using data from a large, household-randomised trial in Houndé, Burkina Faso and Bougouni, Mali. METHODS AND FINDINGS The parent trial evaluated monthly SMC plus either azithromycin (AZ) or placebo, administered as directly observed therapy 4 times per year between August and November (2014-2016). In July 2014, 19,578 children aged 3-59 months were randomised by household to study group. Children who remained within the age range 3-59 months in August each year, plus children born into study households or who moved into the study area, received study drugs in 2015 and 2016. These analyses focus on the approximately 10,000 children (5,000 per country) under observation each year in the SMC plus placebo group. Despite high coverage and high adherence to SMC, the incidence of hospitalisations or deaths due to malaria and uncomplicated clinical malaria remained high in the study areas (overall incidence rates 12.5 [95% confidence interval (CI): 11.2, 14.1] and 871.1 [95% CI: 852.3, 890.6] cases per 1,000 person-years, respectively) and peaked in July each year, before SMC delivery began in August. The incidence rate ratio comparing SMC within the past 28 days with SMC more than 35 days ago-adjusted for age, country, and household clustering-was 0.13 (95% CI: 0.08, 0.20), P < 0.001 for malaria hospitalisations and deaths from malaria and 0.21 (95% CI 0.20, 0.23), P < 0.001 for uncomplicated malaria, indicating protective efficacy of 87.4% (95% CI: 79.6%, 92.2%) and 78.3% (95% CI: 76.8%, 79.6%), respectively. The prevalence of malaria parasitaemia at weekly surveys during the rainy season and at the end of the transmission season was several times higher in children who missed the SMC course preceding the survey contact, and the smallest prevalence ratio observed was 2.98 (95% CI: 1.95, 4.54), P < 0.001. The frequency of molecular markers of sulfadoxine-pyrimethamine (SP) and amodiaquine (AQ) resistance did not increase markedly over the study period either amongst study children or amongst school-age children resident in the study areas. After 3 years of SMC deployment, the day 28 PCR-unadjusted adequate clinical and parasitological response rate of the SP + AQ regimen in children with asymptomatic malaria was 98.3% (95% CI: 88.6%, 99.8%) in Burkina Faso and 96.1% (95% CI: 91.5%, 98.2%) in Mali. Key limitations of this study are the potential overdiagnosis of uncomplicated malaria by rapid diagnostic tests and the potential for residual confounding from factors related to adherence to the monthly SMC schedule. CONCLUSION Despite strong evidence that SMC is providing a high level of protection, the burden of malaria remains substantial in the 2 study areas. These results emphasise the need for continuing support of SMC programmes. A fifth monthly SMC course is needed to adequately cover the whole transmission season in the study areas and in settings with similar epidemiology. TRIAL REGISTRATION The AZ-SMC trial in which these data were collected was registered at clinicaltrials.gov: NCT02211729.
Collapse
Affiliation(s)
- Matthew E. Cairns
- Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, United Kingdom
- * E-mail:
| | | | - Issaka Zongo
- Institut de Recherche en Sciences de la Santé, Bobo Dioulasso, Burkina Faso
| | - Irene Kuepfer
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Frederic Nikiema
- 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
| | - Amadou Barry
- Malaria Research and Training Centre, Bamako, Mali
| | | | | | - Paul Milligan
- Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Halidou Tinto
- Institut de Recherche en Sciences de la Santé, Bobo Dioulasso, Burkina Faso
| | | | - Daniel Chandramohan
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Brian Greenwood
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | |
Collapse
|
18
|
Malaria Outbreak Facilitated by Appearance of Vector-Breeding Sites after Heavy Rainfall and Inadequate Preventive Measures: Nwoya District, Northern Uganda, February-May 2018. JOURNAL OF ENVIRONMENTAL AND PUBLIC HEALTH 2020; 2020:5802401. [PMID: 32377206 PMCID: PMC7193302 DOI: 10.1155/2020/5802401] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 03/16/2020] [Accepted: 03/21/2020] [Indexed: 12/23/2022]
Abstract
Background Malaria is a leading cause of morbidity and mortality in Uganda. In April 2018, malaria cases surged in Nwoya District, Northern Uganda, exceeding expected limits and thereby requiring epidemic response. We investigated this outbreak to estimate its magnitude, identify exposure factors for transmission, and recommend evidence-based control measures. Methods We defined a malaria case as onset of fever in a resident of Anaka subcounty, Koch Goma subcounty, and Nwoya Town Council, Nwoya District, with a positive rapid diagnostic test or microscopy for malaria from 1 February to 25 May 2018. We reviewed medical records in all health facilities of affected subcounties to find cases. In a case-control study, we compared exposure factors between case-persons and asymptomatic controls matched by age and village. We also conducted entomological assessments on vector density and behavior. Results We identified 3,879 case-persons (attack rate [AR] = 6.5%) and two deaths (case-fatality rate = 5.2/10,000). Females (AR = 8.1%) were more affected than males (AR = 4.7%) (p < 0.0001). Of all age groups, 5–18 years (AR = 8.4%) were most affected. Heavy rain started in early March 2018, and a propagated outbreak followed in the first week of April 2018. In the case-control study, 55% (59/107) of case-persons and 18% (19/107) of controls had stagnant water around households for several days following rainfall (ORM-H = 5.6, 95% CI = 3.0–11); 25% (27/107) of case-persons and 51% (55/107) of controls wore full extremity covering clothes during evening hours (ORM-H = 0.30, 95% CI = 0.20–0.60); 71% (76/107) of case-persons and 85% (91/107) of controls slept under a long-lasting insecticide-treated net (LLIN) 14 days before symptom onset (ORM-H = 0.43, 95% CI = 0.22–0.85); 37% (40/107) of case-persons and 52% (56/107) of controls had access to at least one LLIN per 2 household members (ORM-H = 0.54, 95% CI = 0.30–0.97). Entomological assessment indicated active breeding sites in the entire study area; Anopheles gambiae sensu lato species were the predominant vector. Conclusion Increased vector-breeding sites after heavy rainfall and inadequate malaria preventive measures were found to have contributed to this outbreak. We recommended increasing coverage for LLINs and larviciding breeding sites in the area.
Collapse
|