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Ranjit A, Wylie BJ. Malaria in Pregnancy, Current Challenges, and Emerging Prevention Strategies in a Warming Climate. Clin Obstet Gynecol 2024; 67:620-632. [PMID: 39061127 DOI: 10.1097/grf.0000000000000888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Malaria still presents a grave threat to the health of pregnancies worldwide with prevention currently stalling as traditional control and prevention strategies are limited by both insecticide and drug resistance. Furthermore, climate change is bringing malaria to locations where it was once eradicated and intensifying malaria in other areas. Even where malaria is not currently common, obstetricians will need to understand the pathogenesis of the disease, how it is transmitted, methods for prevention and treatment in pregnancy, and promising emerging strategies such as vaccines. A renewed global response is needed for this age-old disease in which pregnancy poses specific susceptibility.
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Affiliation(s)
- Anju Ranjit
- Department of Obstetrics, Gynecology and Reproductive Sciences, Division of Maternal-Fetal Medicine, University of California, San Francisco
| | - Blair J Wylie
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, Columbia University Medical Center, New York, New York
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Diawara H, Healy SA, Mwakingwe-Omari A, Issiaka D, Diallo A, Traore S, Soumbounou IH, Gaoussou S, Zaidi I, Mahamar A, Attaher O, Fried M, Wylie BJ, Mohan R, Doan V, Doritchamou JYA, Dolo A, Morrison RD, Wang J, Hu Z, Rausch KM, Zeguime A, Murshedkar T, Kc N, Sim BKL, Billingsley PF, Richie TL, Hoffman SL, Dicko A, Duffy PE. Safety and efficacy of PfSPZ Vaccine against malaria in healthy adults and women anticipating pregnancy in Mali: two randomised, double-blind, placebo-controlled, phase 1 and 2 trials. THE LANCET. INFECTIOUS DISEASES 2024:S1473-3099(24)00360-8. [PMID: 39153490 DOI: 10.1016/s1473-3099(24)00360-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 05/07/2024] [Accepted: 05/30/2024] [Indexed: 08/19/2024]
Abstract
BACKGROUND Plasmodium falciparum parasitaemia during pregnancy causes maternal, fetal, and infant mortality. Poor pregnancy outcomes are related to blood-stage parasite sequestration and the ensuing inflammatory response in the placenta, which decreases over successive pregnancies. A radiation-attenuated, non-replicating, whole-organism vaccine based on P falciparum sporozoites (PfSPZ Vaccine) has shown efficacy at preventing infection in African adults. Here, we aimed to examine vaccine safety and efficacy of the PfSPZ Vaccine in adults and women who anticipated conception. METHODS Two randomised, double-blind, placebo-controlled trials (phase 1 MLSPZV3 and phase 2 MLSPZV4) were conducted at a clinical research centre in Mali. MLSPZV3 included adults aged 18-35 years and MLSPZV4 included non-pregnant women aged 18-38 years who anticipated conception within a year of enrolment. In MLSPZV3, participants were stratified by village and randomly assigned (2:1) using block randomisation to receive three doses of 9 × 105 PfSPZ Vaccine or saline placebo at weeks 0, 1, and 4 (4-week schedule) or at weeks 0, 8, and 16 (16-week schedule) and a booster dose around 1 year later. In MLSPZV4, women received presumptive artemether-lumefantrine twice per day for 3 days 2 weeks before dose one and were randomly assigned (1:1:1) using block randomisation to receive three doses of 9 × 105 or 1·8 × 106 PfSPZ Vaccine or saline placebo all administered at weeks 0, 1, and 4 (4-week schedule). Participants in both studies received artemether-lumefantrine 2 weeks before dose three and additionally 2 weeks before dose four (booster dose) in MLSPZV3. Investigators and participants were masked to group assignment. The primary outcome, assessed in the as-treated population, was PfSPZ Vaccine safety and tolerability within 7 days after each dose. The secondary outcome, assessed in the modified intention-to-treat population, was vaccine efficacy against P falciparum parasitaemia (defined as the time-to-first positive blood smear) from dose three until the end of transmission season. In exploratory analyses, MLSPZV4 evaluated incidence of maternal obstetric and neonatal outcomes as safety outcomes, and vaccine efficacy against P falciparum parasitaemia during pregnancy (defined as time-to-first positive blood smear post-conception). In MLSPZV4, women were followed at least once a month with human chorionic gonadotropin testing, and those who became pregnant received standard of care (including intermittent presumptive sulfadoxine-pyrimethamine antimalarial drugs after the first trimester) during routine antenatal visits. These studies are registered with ClinicalTrials.gov, NCT03510481 and NCT03989102. FINDINGS Participants were enrolled for vaccination during the onset of malaria seasons for two sequential studies conducted from 2018 to 2019 for MLSPZV3 and from 2019 to 2021 for MLSPZV4, with follow-up during malaria seasons across 2 years. In MLSPZV3, 478 adults were assessed for eligibility, of whom 220 were enrolled between May 30 and June 12, 2018, and then between Aug 13 and Aug 18, 2018, and 210 received dose one. 66 (96%) of 69 participants who received the 16-week schedule and 68 (97%) of 70 who received the 4-week schedule of the 9 × 105 PfSPZ Vaccine and 70 (99%) of 71 who received saline completed all three doses in year 1. In MLSPZV4, 407 women were assessed for eligibility, of whom 324 were enrolled from July 3 to July 27, 2019, and 320 received dose one of presumptive artemether-lumefantrine. 300 women were randomly assigned with 100 per group (PfSPZ Vaccine 9 × 105, 1·8 × 106, or saline) receiving dose one. First trimester miscarriages were the most commonly reported serious adverse event but occurred at a similar rate across study groups (eight [15%] of 54 with 9 × 105 PfSPZ Vaccine, 12 [21%] of 58 with 1·8 × 106 PfSPZ Vaccine, and five [12%] of 43 with saline). One unrelated maternal death occurred 425 days after the last vaccine dose in the 1·8 × 106 PfSPZ Vaccine group due to peritonitis shortly after childbirth. Most related adverse events reported in MLSPZV3 and MLSPZV4 were mild (grade 1) and frequency of adverse events in the PfSPZ Vaccine groups did not differ from that in the saline group. Two unrelated serious adverse events occurred in MLSPZV3 (one participant had appendicitis in the 9 × 105 PfSPZ Vaccine group and the other in the saline group died due to a road traffic accident). In MLSPZV3, the 9 × 105 PfSPZ Vaccine did not show vaccine efficacy against parasitaemia with the 4-week (27% [95% CI -18 to 55] in year 1 and 42% [-5 to 68] in year 2) and 16-week schedules (16% [-34 to 48] in year 1 and -14% [-95 to 33] in year 2); efficacies were similar or worse against clinical malaria compared with saline. In MLSPZV4, the PfSPZ Vaccine showed significant efficacy against parasitaemia at doses 9 × 105 (41% [15 to 59]; p=0·0069 in year 1 and 61% [36 to 77]; p=0·0011 in year 2) and 1·8 × 106 (54% [34 to 69]; p<0·0001 in year 1 and 45% [13 to 65]; p=0·029 in year 2); and against clinical malaria at doses 9 × 105 (47% [20 to 65]; p=0·0045 in year 1 and 56% [22 to 75]; p=0·0081 in year 2) and 1·8 × 106 (48% [22 to 65]; p=0·0013 in year 1 and 40% [2 to 64]; p=0·069 in year 2). Vaccine efficacy against post-conception P falciparum parasitaemia during first pregnancies that arose in the 2-year follow-up was 57% (14 to 78; p=0·017) in the 9 × 105 PfSPZ Vaccine group versus 49% (3 to 73; p=0·042) in the 1·8 × 106 PfSPZ Vaccine group. Among 55 women who became pregnant within 24 weeks after dose three, vaccine efficacy against parasitaemia was 65% (23 to 84; p=0·0088) with the 9 × 105 PfSPZ Vaccine and 86% (64 to 94; p<0·0001) with the 1·8 × 106 PfSPZ Vaccine. When combined in a post-hoc analysis, women in the PfSPZ Vaccine groups had a non-significantly reduced time-to-first pregnancy after dose one compared with those in the saline group (log-rank test p=0·056). Exploratory maternal obstetric and neonatal outcomes did not differ significantly between vaccine groups and saline. INTERPRETATION PfSPZ Vaccine was safe and well tolerated in adults in Mali. The 9 × 105 and 1·8 × 106 doses of PfSPZ Vaccine administered as per the 4-week schedule, which incorporated presumptive antimalarial treatment before the first vaccine dose, showed significant efficacy against P falciparum parasitaemia and clinical malaria for two malaria transmission seasons in women of childbearing age and against pregnancy malaria. PfSPZ Vaccine without presumptive antimalarial treatment before the first vaccine dose did not show efficacy. FUNDING National Institute of Allergy and Infectious Diseases, National Institutes of Health, and Sanaria.
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Affiliation(s)
- Halimatou Diawara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Sara A Healy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Agnes Mwakingwe-Omari
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Djibrilla Issiaka
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Aye Diallo
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Seydou Traore
- 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
| | - Santara Gaoussou
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Irfan Zaidi
- 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
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Blair J Wylie
- Columbia University Medical Center, Columbia University, New York, NY, USA
| | - Rathy Mohan
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Viyada Doan
- 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
| | - Amagana Dolo
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies of Bamako, Bamako, Mali
| | - Robert D Morrison
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jing Wang
- Clinical Monitoring Research Program Directorate, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Zonghui Hu
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Kelly M Rausch
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Amatigue Zeguime
- 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, National Institutes of Health, Bethesda, MD, USA.
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Chinawa AT, Ossai EN, Onukwuli VO, Nduagubam OC, Uwaezuoke NA, Okafor CN, Chinawa JM. Willingness to accept malaria vaccines amongst women presenting at outpatient and immunization clinics in Enugu state, Southeast Nigeria. Malar J 2024; 23:117. [PMID: 38664783 PMCID: PMC11044559 DOI: 10.1186/s12936-024-04914-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 03/21/2024] [Indexed: 04/29/2024] Open
Abstract
BACKGROUND There are giant steps taken in the introduction of the novel malaria vaccine poised towards reducing mortality and morbidity associated with malaria. OBJECTIVES This study aimed to determine the knowledge of malaria vaccine and factors militating against willingness to accept the vaccine among mothers presenting in nine hospitals in Enugu metropolis. METHODS This was a cross-sectional study carried out among 491 mothers who presented with their children in nine hospitals in Enugu metropolis, South-East Nigeria. A pre-tested and interviewer-administered questionnaire was used in this study. RESULTS A majority of the respondents, 72.1% were aware of malaria vaccine. A majority of the respondents, 83.1% were willing to receive malaria vaccine. Similarly, a majority of the mothers, 92.9%, were willing to vaccinate baby with the malaria vaccine, while 81.1% were willing to vaccinate self and baby with the malaria vaccine. The subjects who belong to the low socio-economic class were five times less likely to vaccinate self and baby with malaria vaccine when compared with those who were in the high socio-economic class (AOR = 0.2, 95% CI 0.1-0.5). Mothers who had good knowledge of malaria vaccination were 3.3 times more likely to vaccinate self and baby with malaria vaccine when compared with those who had poor knowledge of malaria vaccination (AOR = 3.3, 95% CI 1-6-6.8). CONCLUSION Although the study documented a high vaccine acceptance among the mothers, there exists a poor knowledge of the malaria vaccine among them.
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Affiliation(s)
- Awoere T Chinawa
- Department of Community Medicine, College of Medicine ESUT, Enugu, Nigeria
| | - Edmund N Ossai
- Department of Community Medicine, Ebonyi State University, Abakaliki, Ebonyi State, Nigeria
| | | | - Obinna C Nduagubam
- Department of Paediatrics, College of Medicine, Enugu State University of Technology, Enugu, Nigeria
| | | | - Chinyere N Okafor
- Department of Community Medicine, College of Medicine UNEC, Enugu, Nigeria.
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Chinawa AT, Ossai EN, Onukwuli VO, Nduagubam OC, Uwaezuoke NA, Okafor CN, Chinawa JM. Willingness to accept malaria vaccines amongst women presenting at outpatient and immunization clinics in Enugu state, Southeast Nigeria. Malar J 2024; 23:117. [DOI: https:/doi.org/10.1186/s12936-024-04914-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 03/21/2024] [Indexed: 04/30/2024] Open
Abstract
Abstract
Background
There are giant steps taken in the introduction of the novel malaria vaccine poised towards reducing mortality and morbidity associated with malaria.
Objectives
This study aimed to determine the knowledge of malaria vaccine and factors militating against willingness to accept the vaccine among mothers presenting in nine hospitals in Enugu metropolis.
Methods
This was a cross-sectional study carried out among 491 mothers who presented with their children in nine hospitals in Enugu metropolis, South-East Nigeria. A pre-tested and interviewer-administered questionnaire was used in this study.
Results
A majority of the respondents, 72.1% were aware of malaria vaccine. A majority of the respondents, 83.1% were willing to receive malaria vaccine. Similarly, a majority of the mothers, 92.9%, were willing to vaccinate baby with the malaria vaccine, while 81.1% were willing to vaccinate self and baby with the malaria vaccine. The subjects who belong to the low socio-economic class were five times less likely to vaccinate self and baby with malaria vaccine when compared with those who were in the high socio-economic class (AOR = 0.2, 95% CI 0.1–0.5). Mothers who had good knowledge of malaria vaccination were 3.3 times more likely to vaccinate self and baby with malaria vaccine when compared with those who had poor knowledge of malaria vaccination (AOR = 3.3, 95% CI 1–6–6.8).
Conclusion
Although the study documented a high vaccine acceptance among the mothers, there exists a poor knowledge of the malaria vaccine among them.
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Devaraju M, Li A, Ha S, Li M, Shivakumar M, Li H, Nishiguchi EP, Gérardin P, Waldorf KA, Al-Haddad BJS. Beyond TORCH: A narrative review of the impact of antenatal and perinatal infections on the risk of disability. Neurosci Biobehav Rev 2023; 153:105390. [PMID: 37708918 PMCID: PMC10617835 DOI: 10.1016/j.neubiorev.2023.105390] [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: 06/13/2023] [Revised: 09/07/2023] [Accepted: 09/10/2023] [Indexed: 09/16/2023]
Abstract
Infections and inflammation during pregnancy or early life can alter child neurodevelopment and increase the risk for structural brain abnormalities and mental health disorders. There is strong evidence that TORCH infections (i.e., Treponema pallidum, Toxoplasma gondii, rubella virus, cytomegalovirus, herpes virus) alter fetal neurodevelopment across multiple developmental domains and contribute to motor and cognitive disabilities. However, the impact of a broader range of viral and bacterial infections on fetal development and disability is less well understood. We performed a literature review of human studies to identify gaps in the link between maternal infections, inflammation, and several neurodevelopmental domains. We found strong and moderate evidence respectively for a higher risk of motor and cognitive delays and disabilities in offspring exposed to a range of non-TORCH pathogens during fetal life. In contrast, there is little evidence for an increased risk of language and sensory disabilities. While guidelines for TORCH infection prevention during pregnancy are common, further consideration for prevention of non-TORCH infections during pregnancy for fetal neuroprotection may be warranted.
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Affiliation(s)
- Monica Devaraju
- University of Washington, School of Medicine, 1959 NE Pacific St, Seattle, WA 98195, USA; University of Washington, Department of Obstetrics, 1959 NE Pacific St, Seattle, WA 98195, USA
| | - Amanda Li
- University of Washington, Department of Obstetrics, 1959 NE Pacific St, Seattle, WA 98195, USA; Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH, USA
| | - Sandy Ha
- University of Washington, Department of Obstetrics, 1959 NE Pacific St, Seattle, WA 98195, USA
| | - Miranda Li
- University of Washington, School of Medicine, 1959 NE Pacific St, Seattle, WA 98195, USA; University of Washington, Department of Obstetrics, 1959 NE Pacific St, Seattle, WA 98195, USA
| | - Megana Shivakumar
- University of Washington, Department of Obstetrics, 1959 NE Pacific St, Seattle, WA 98195, USA
| | - Hanning Li
- University of Washington, Department of Obstetrics, 1959 NE Pacific St, Seattle, WA 98195, USA
| | - Erika Phelps Nishiguchi
- University of Hawaii, Department of Pediatrics, Division of Community Pediatrics, 1319 Punahou St, Honolulu, HI, USA
| | - Patrick Gérardin
- INSERM CIC1410, Centre Hospitalier Universitaire de la Réunion, Saint Pierre, Réunion, France; Platform for Clinical and Translational Research, Centre Hospitalier Universitaire, Saint Pierre, Réunion, France
| | - Kristina Adams Waldorf
- University of Washington, Department of Obstetrics, 1959 NE Pacific St, Seattle, WA 98195, USA.
| | - Benjamin J S Al-Haddad
- University of Minnesota, Department of Pediatrics, Division of Neonatology, Academic Office Building, 2450 Riverside Ave S AO-401, Minneapolis, MN 55454, USA; Masonic Institute for the Developing Brain, 2025 E River Pkwy, Minneapolis, MN 55414, USA.
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Wiser MF. Knobs, Adhesion, and Severe Falciparum Malaria. Trop Med Infect Dis 2023; 8:353. [PMID: 37505649 PMCID: PMC10385726 DOI: 10.3390/tropicalmed8070353] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 06/30/2023] [Accepted: 07/02/2023] [Indexed: 07/29/2023] Open
Abstract
Plasmodium falciparum can cause a severe disease with high mortality. A major factor contributing to the increased virulence of P. falciparum, as compared to other human malarial parasites, is the sequestration of infected erythrocytes in the capillary beds of organs and tissues. This sequestration is due to the cytoadherence of infected erythrocytes to endothelial cells. Cytoadherence is primarily mediated by a parasite protein expressed on the surface of the infected erythrocyte called P. falciparum erythrocyte membrane protein-1 (PfEMP1). PfEMP1 is embedded in electron-dense protuberances on the surface of the infected erythrocytes called knobs. These knobs are assembled on the erythrocyte membrane via exported parasite proteins, and the knobs function as focal points for the cytoadherence of infected erythrocytes to endothelial cells. PfEMP1 is a member of the var gene family, and there are approximately 60 antigenically distinct PfEMP1 alleles per parasite genome. Var gene expression exhibits allelic exclusion, with only a single allele being expressed by an individual parasite. This results in sequential waves of antigenically distinct infected erythrocytes and this antigenic variation allows the parasite to establish long-term chronic infections. A wide range of endothelial cell receptors can bind to the various PfEMP1 alleles, and thus, antigenic variation also results in a change in the cytoadherence phenotype. The cytoadherence phenotype may result in infected erythrocytes sequestering in different tissues and this difference in sequestration may explain the wide range of possible clinical manifestations associated with severe falciparum malaria.
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Affiliation(s)
- Mark F Wiser
- Department of Tropical Medicine and Infectious Disease, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, New Orleans, LA 70112, USA
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Emanuel EJ, Persad G. The shared ethical framework to allocate scarce medical resources: a lesson from COVID-19. Lancet 2023:S0140-6736(23)00812-7. [PMID: 37172603 PMCID: PMC10168660 DOI: 10.1016/s0140-6736(23)00812-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 01/20/2023] [Accepted: 01/31/2023] [Indexed: 05/15/2023]
Abstract
The COVID-19 pandemic has helped to clarify the fair and equitable allocation of scarce medical resources, both within and among countries. The ethical allocation of such resources entails a three-step process: (1) elucidating the fundamental ethical values for allocation, (2) using these values to delineate priority tiers for scarce resources, and (3) implementing the prioritisation to faithfully realise the fundamental values. Myriad reports and assessments have elucidated five core substantive values for ethical allocation: maximising benefits and minimising harms, mitigating unfair disadvantage, equal moral concern, reciprocity, and instrumental value. These values are universal. None of the values are sufficient alone, and their relative weight and application will vary by context. In addition, there are procedural principles such as transparency, engagement, and evidence-responsiveness. Prioritising instrumental value and minimising harms during the COVID-19 pandemic led to widespread agreement on priority tiers to include health-care workers, first responders, people living in congregate housing, and people with an increased risk of death, such as older adults and individuals with medical conditions. However, the pandemic also revealed problems with the implementation of these values and priority tiers, such as allocation on the basis of population rather than COVID-19 burden, and passive allocation that exacerbated disparities by requiring recipients to spend time booking and travelling to appointments. This ethical framework should be the starting point for the allocation of scarce medical resources in future pandemics and other public health conditions. For instance, allocation of the new malaria vaccine among sub-Saharan African countries should be based not on reciprocity to countries that participated in research, but on maximally reducing serious illness and deaths, especially among infants and children.
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Affiliation(s)
- Ezekiel J Emanuel
- Healthcare Transformation Institute, Department of Medical Ethics & Health Policy, Perelman School of Medicine and Wharton School, University of Pennsylvania, Philadelphia, PA, USA.
| | - Govind Persad
- Sturm College of Law, University of Denver, Denver, CO, 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] [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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9
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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] [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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10
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Rotich AK, Takashima E, Yanow SK, Gitaka J, Kanoi BN. Towards identification and development of alternative vaccines against pregnancy-associated malaria based on naturally acquired immunity. FRONTIERS IN TROPICAL DISEASES 2022. [DOI: 10.3389/fitd.2022.988284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Pregnant women are particularly susceptible to Plasmodium falciparum malaria, leading to substantial maternal and infant morbidity and mortality. While highly effective malaria vaccines are considered an essential component towards malaria elimination, strides towards development of vaccines for pregnant women have been minimal. The leading malaria vaccine, RTS,S/AS01, has modest efficacy in children suggesting that it needs to be strengthened and optimized if it is to be beneficial for pregnant women. Clinical trials against pregnancy-associated malaria (PAM) focused on the classical VAR2CSA antigen are ongoing. However, additional antigens have not been identified to supplement these initiatives despite the new evidence that VAR2CSA is not the only molecule involved in pregnancy-associated naturally acquired immunity. This is mainly due to a lack of understanding of the immune complexities in pregnancy coupled with difficulties associated with expression of malaria recombinant proteins, low antigen immunogenicity in humans, and the anticipated complications in conducting and implementing a vaccine to protect pregnant women. With the accelerated evolution of molecular technologies catapulted by the global pandemic, identification of novel alternative vaccine antigens is timely and feasible. In this review, we discuss approaches towards novel antigen discovery to support PAM vaccine studies.
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11
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Kumar M, Saadaoui M, Al Khodor S. Infections and Pregnancy: Effects on Maternal and Child Health. Front Cell Infect Microbiol 2022; 12:873253. [PMID: 35755838 PMCID: PMC9217740 DOI: 10.3389/fcimb.2022.873253] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 05/04/2022] [Indexed: 12/22/2022] Open
Abstract
Pregnancy causes physiological and immunological adaptations that allow the mother and fetus to communicate with precision in order to promote a healthy pregnancy. At the same time, these adaptations may make pregnant women more susceptible to infections, resulting in a variety of pregnancy complications; those pathogens may also be vertically transmitted to the fetus, resulting in adverse pregnancy outcomes. Even though the placenta has developed a robust microbial defense to restrict vertical microbial transmission, certain microbial pathogens have evolved mechanisms to avoid the placental barrier and cause congenital diseases. Recent mechanistic studies have begun to uncover the striking role of the maternal microbiota in pregnancy outcomes. In this review, we discuss how microbial pathogens overcome the placental barrier to cause congenital diseases. A better understanding of the placental control of fetal infection should provide new insights into future translational research.
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Affiliation(s)
- Manoj Kumar
- Research Department, Sidra Medicine, Doha, Qatar
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12
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Aleshnick M, Florez-Cuadros M, Martinson T, Wilder BK. Monoclonal antibodies for malaria prevention. Mol Ther 2022; 30:1810-1821. [PMID: 35395399 PMCID: PMC8979832 DOI: 10.1016/j.ymthe.2022.04.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/04/2022] [Accepted: 04/01/2022] [Indexed: 11/29/2022] Open
Abstract
Monoclonal antibodies are highly specific proteins that are cloned from a single B cell and bind to a single epitope on a pathogen. These laboratory-made molecules can serve as prophylactics or therapeutics for infectious diseases and have an impressive capacity to modulate the progression of disease, as demonstrated for the first time on a large scale during the COVID-19 pandemic. The high specificity and natural starting point of monoclonal antibodies afford an encouraging safety profile, yet the high cost of production remains a major limitation to their widespread use. While a monoclonal antibody approach to abrogating malaria infection is not yet available, the unique life cycle of the malaria parasite affords many opportunities for such proteins to act, and preliminary research into the efficacy of monoclonal antibodies in preventing malaria infection, disease, and transmission is encouraging. This review examines the current status and future outlook for monoclonal antibodies against malaria in the context of the complex life cycle and varied antigenic targets expressed in the human and mosquito hosts, and provides insight into the strengths and limitations of this approach to curtailing one of humanity’s oldest and deadliest diseases.
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Affiliation(s)
- Maya Aleshnick
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, Oregon, USA
| | | | - Thomas Martinson
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, Oregon, USA
| | - Brandon K Wilder
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, Oregon, USA; Department of Parasitology, U.S. Naval Medical Research 6 (NAMRU-6), Lima, Peru
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13
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Vaccines. SIDE EFFECTS OF DRUGS ANNUAL 2022. [PMCID: PMC9646283 DOI: 10.1016/bs.seda.2022.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The safety of COVID-19 vaccines, as was the case last year, remains a large part of the focus in this volume. COVID-19 placed a large magnifying glass on both vaccines, specifically vaccine safety. This was most readily apparent as the number of records in VAERS ballooned to about 10 times the size from 2020 to 2021 (Vaccine Adverse Event Reporting System (VAERS), 2022) [S]. While we have added and/or improved VAERS during COVID-19, including adding or improving other vaccine safety surveillance tools like v-safe and vaccine safety datalink (Blumenthal, Phadke, et al., 2021) [MC], there is still room for improvement in these pharmacovigilance tools (Rizk et al., 2021) [r]. A major global initiative in this realm is the Global Vaccines Safety Blueprint 2.0 (GVSB2.0) (Organization, 2021, pp. 2021–2023) [S]. We wholeheartedly endorse these initiatives, which could significantly improve vaccine safety. As noted in past SEDA issues, clinicians should be mindful of the risks of AEs and SAEs associated with each individual vaccine.
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14
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Future vaccines in pregnancy. Best Pract Res Clin Obstet Gynaecol 2021; 76:96-106. [PMID: 33893037 PMCID: PMC7987580 DOI: 10.1016/j.bpobgyn.2021.03.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 02/24/2021] [Accepted: 03/16/2021] [Indexed: 01/04/2023]
Abstract
Vaccination in pregnancy provides an important opportunity to target illnesses that are known to impact pregnant women, fetal development, and newborns in particular. The ability to create antibodies through safe vaccination that cross the placenta can provide protection against maternal, congenital, and newborn infections. At present, multiple vaccines are being developed which have direct benefits for pregnant women and their newborns. Group B streptococcus, Respiratory Syncytial Virus, Cytomegalovirus, Zika, Ebola, Malaria, and Coronavirus SARS-CoV-2 are all being researched with the view to develop a safe vaccine available for pregnant women. There is also an increased movement towards the inclusion of pregnant women in vaccine development and trials - challenging the historical, ethical, and medicolegal arguments against their involvement in such research.
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15
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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] [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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16
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Abstract
Introduction: An effective vaccine against malaria forms a global health priority. Both naturally acquired immunity and sterile protection induced by irradiated sporozoite immunization were described decades ago. Still no vaccine exists that sufficiently protects children in endemic areas. Identifying immunological correlates of vaccine efficacy can inform rational vaccine design and potentially accelerate clinical development.Areas covered: We discuss recent research on immunological correlates of malaria vaccine efficacy, including: insights from state-of-the-art omics platforms and systems vaccinology analyses; functional anti-parasitic assays; pre-immunization predictors of vaccine efficacy; and comparison of correlates of vaccine efficacy against controlled human malaria infections (CHMI) and against naturally acquired infections.Expert Opinion: Effective vaccination may be achievable without necessarily understanding immunological correlates, but the relatively disappointing efficacy of malaria vaccine candidates in target populations is concerning. Hypothesis-generating omics and systems vaccinology analyses, alongside assessment of pre-immunization correlates, have the potential to bring about paradigm-shifts in malaria vaccinology. Functional assays may represent in vivo effector mechanisms, but have scarcely been formally assessed as correlates. Crucially, evidence is still meager that correlates of vaccine efficacy against CHMI correspond with those against naturally acquired infections in target populations. Finally, the diversity of immunological assays and efficacy endpoints across malaria vaccine trials remains a major confounder.
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Affiliation(s)
| | - Matthew B B McCall
- Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, The Netherlands.,Institut für Tropenmedizin, Universitätsklinikum Tübingen, Tübingen, Germany.,Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
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17
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Sadarangani M, Kollmann T, Bjornson G, Heath P, Clarke E, Marchant A, Levy O, Leuridan E, Ulloa-Gutierrez R, Cutland CL, Kampmann B, Chaithongwongwatthana S, Dinleyici E, van Damme P, Munoz FM. The Fifth International Neonatal and Maternal Immunization Symposium (INMIS 2019): Securing Protection for the Next Generation. mSphere 2021; 6:e00862-20. [PMID: 33504658 PMCID: PMC7885317 DOI: 10.1128/msphere.00862-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Despite significant progress in reaching some milestones of the United Nations Sustainable Development Goals, neonatal and early infant morbidity and mortality remain high, and maternal health remains suboptimal in many countries. Novel and improved preventative strategies with the potential to benefit pregnant women and their infants are needed, with maternal and neonatal immunization representing effective approaches. Experts from immunology, vaccinology, infectious diseases, clinicians, industry, public health, and vaccine-related social sciences convened at the 5th International Neonatal and Maternal Immunization Symposium (INMIS) in Vancouver, Canada, from 15 to 17 September 2019. We critically evaluated the lessons learned from recent clinical studies, presented cutting-edge scientific progress in maternal and neonatal immunology and vaccine development, and discussed maternal and neonatal immunization in the broader context of infectious disease epidemiology and public health. Focusing on practical aspects of research and implementation, we also discussed the safety, awareness, and perception of maternal immunization as an existing strategy to address the need to improve maternal and neonatal health worldwide. The symposium provided a comprehensive scientific and practical primer as well as an update for all those with an interest in maternal and neonatal infection, immunity, and vaccination. The summary presented here provides an update of the current status of progress in maternal and neonatal immunization.
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Affiliation(s)
- Manish Sadarangani
- Vaccine Evaluation Center, BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada
- Division of Infectious Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Tobias Kollmann
- Telethon Kids Institute, Perth Children's Hospital, University of Western Perth, Perth, Australia
| | - Gordean Bjornson
- Vaccine Evaluation Center, BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada
| | - Paul Heath
- St. George's University of London, London, United Kingdom
| | - Ed Clarke
- Vaccines & Immunity Theme, Medical Research Council Unit, The Gambia, London School of Hygiene and Tropical Medicine (MRCG at LSHTM), Banjul, The Gambia
| | - Arnaud Marchant
- Institute for Medical Immunology, Université Libre de Bruxelles, Charleroi, Belgium
| | - Ofer Levy
- Precision Vaccines Program, Division of Infectious Diseases, Boston Children's Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
- Broad Institute of MIT & Harvard, Cambridge, Massachusetts, USA
| | - Elke Leuridan
- Centre for the Evaluation of Vaccination, Vaccine & Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Rolando Ulloa-Gutierrez
- Hospital Nacional de Niños Dr. Carlos Sáenz Herrera, Centro de Ciencias Médicas C.C.S.S., San José, Costa Rica
| | - Clare L Cutland
- African Leadership in Vaccinology Expertise (ALIVE), Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Beate Kampmann
- Vaccines & Immunity Theme, Medical Research Council Unit, The Gambia, London School of Hygiene and Tropical Medicine (MRCG at LSHTM), Banjul, The Gambia
- The Vaccine Centre, Clinical Research Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Surasith Chaithongwongwatthana
- Division of Infectious Disease in Gynecology and Obstetrics (InDiGO), Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Ener Dinleyici
- Eskisehir Osmangazi University, Faculty of Medicine, Eskisehir, Turkey
| | - Pierre van Damme
- Centre for the Evaluation of Vaccination, Vaccine & Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Flor M Munoz
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA
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Ferluga J, Singh I, Rout S, Al-Qahtani A, Yasmin H, Kishore U. Immune Responses in Malaria and Vaccine Strategies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1313:273-291. [PMID: 34661899 DOI: 10.1007/978-3-030-67452-6_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Malaria is a pandemic with nearly half of global population at risk, caused by parasite Plasmodium species, particularly P. falciparum with a high morbidity and mortality, especially among children. There is an urgent need for development of population protective vaccines, such as in sub-Saharan low-income countries, where P. falciparum malaria is endemic. After years of endeavour with children and adults for safety and efficacy clinical trials, the P. falciparum circumsporozoite protein antigen, is targeted by specific antibodies induced by recombinant vaccine, called TRS,S. TRS,S has been authorized by WHO and Malawi Government to be the first malaria vaccine for up to 2 years of aged children for protection against malaria. Other malaria vaccines in clinical trials are also very promising candidates, including the original live, X-ray attenuated P-sporozoite vaccine, inducing antigen-specific T cell immunity at liver stage. Malaria parasite at blood symptomatic stage is targeted by specific antibodies to parasite-infected erythrocytes, which are important against pathogenic placenta-infected erythrocyte sequestration. Here, the demographic distribution of Plasmodium species and their pathogenicity in infected people are discussed. The role of innate phagocytic cells and malaria antigen specific T cell immunity, as well as that of specific antibody production by B cells are highlighted. The paramount role of cytotoxic CD8+ T cellular immunity in malaria people protection is also included.
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Affiliation(s)
- Janez Ferluga
- Biosciences, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, UK
| | - Iesha Singh
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Sashmita Rout
- Department of Physiology, All-India Institute of Medical Sciences, Bhubaneswar, India
| | - Ahmed Al-Qahtani
- Department of Infection and Immunity, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Hadida Yasmin
- Immunology and Cell Biology Laboratory, Department of Zoology, Cooch Behar Panchanan Barma University, Cooch Behar, West Bengal, India
| | - Uday Kishore
- Biosciences, College of Health, Medicine and Life Sciences, Brunel University London, Uxbridge, UK
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19
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Vaccines. SIDE EFFECTS OF DRUGS ANNUAL 2021. [PMCID: PMC8488686 DOI: 10.1016/bs.seda.2021.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this volume of the Side Effects of Drugs Annual, although other vaccines will be covered, the safety of COVID vaccines is the focus as COVID-19 has led to heightened attention on vaccine safety in general. As such, this chapter will be more relevant than ever before. As noted in past SEDA issues, clinicians should be mindful of the risks of AEs and SAEs associated with each vaccine.
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20
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Abstract
PURPOSE OF REVIEW Malaria threatens the lives of over 200 million individuals with the disease each year. Plasmodium falciparum is the predominant cause of severe malaria which may be lethal and result in neurocognitive sequelae despite appropriate treatment. We review recent advances regarding the pathophysiology of severe malaria and treatment recommendations for severe disease in the United States. RECENT FINDINGS Infected red blood cell (iRBC) sequestration in microvascular beds is a critical factor in the development of severe malaria syndromes. Interactions between iRBC variant adhesive peptides and the endothelial protein C receptor (EPCR) result in perturbations of coagulation and cytopreservation pathways. Alterations in the protein C/EPCR axis are implicated in cerebral malaria, respiratory distress, and anemia. Brain MRIs reveal the posterior reversible encephalopathy syndrome in cerebral malaria patients. Transcriptomic analysis reveals commonalities in disease pathogenesis in children and adults despite differences in clinical presentation. US guidelines for severe malaria treatment currently recommend intravenous artesunate including in pregnant women and children. SUMMARY Despite advances in our understanding of malarial pathogenesis much remains unknown. Antimalarial agents eradicate parasites but no treatments are available to prevent or ameliorate severe malaria or prevent disease sequelae. Further study is needed to develop effective adjunctive therapies.
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Farrell R, Michie M, Pope R. Pregnant Women in Trials of Covid-19: A Critical Time to Consider Ethical Frameworks of Inclusion in Clinical Trials. Ethics Hum Res 2020; 42:17-23. [PMID: 32562594 PMCID: PMC7323073 DOI: 10.1002/eahr.500060] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Ethical issues abound during this unprecedented international public health crisis of Covid-19. While the trade-off between societal and individual interests that occurs at the intersection of public health ethics and clinical ethics affects all populations, this calculus has particular relevance for pregnant women and the question of when they will have access to new Covid-19 therapies and vaccines. Pregnant women are a "scientifically complex" population whose inclusion in clinical research must be done with consideration of the unique state of pregnancy. Yet research on the impact of Covid-19 on pregnant women is lagging. In a rush to prevent and treat SARS-CoV-2 infection, it is crucial that the interests of pregnant women be prioritized to enable them to make autonomous, informed decisions about participating in clinical trials. The global pandemic calls for a revisiting of frameworks for the inclusion of pregnant women in research, as these women have an important stake in the prevention and treatment of Covid-19.
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Affiliation(s)
- Ruth Farrell
- Vice chair of research in the OB/GYN & Women's Health Institute at the Cleveland Clinic
| | - Marsha Michie
- Assistant professor in the Department of Bioethics at Case Western Reserve University School of Medicine
| | - Rachel Pope
- Obstetrician-gynecologist at University Hospitals Cleveland Medical Center working with the Cuyahoga County Board of Health on Covid-19 management
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22
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Andemel N, Gaoussou S, Barry A, Issiaka D, Mahamar A, Traore M, Duffy PE, Dicko A, Fried M. Adverse pregnancy outcomes among women presenting at antenatal clinics in Ouélessébougou, Mali. Reprod Health 2020; 17:39. [PMID: 32183832 PMCID: PMC7077143 DOI: 10.1186/s12978-020-0890-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 03/04/2020] [Indexed: 01/05/2023] Open
Abstract
Background In sub-Saharan Africa, malaria continues to scourge the population and is the primary cause of morbidity and mortality in young children and pregnant women. As current preventative measures such as intermittent preventive treatment and use of insecticide-treated nets provide incomplete protection, several malaria vaccines are currently under development, including one to specifically prevent pregnancy malaria. Prior to conducting vaccine trials, it is important to obtain background information on poor pregnancy outcomes in the target population to establish a baseline. Methods Pregnant women presenting at community health care centers for antenatal care were recruited to the study. Gestational age was determined by ultrasound examination following recruitment. Antenatal care and pregnancy outcome information were collected during a visit 4–8 weeks post-delivery. Results One thousand eight hundred fifty women completed the study, and analysis included 1814 women after excluding multiple gestations (n = 26) and missing/incomplete data (n = 10). The percentage (95% CI) of adverse pregnancy outcomes is as follows: miscarriage, 0.28% (0.04–0.52); stillbirth, 1.93% (1.30–2.56); early neonatal death, 1.65% (1.03–2.24); late neonatal death, 0.39%, (0.10–0.68); and preterm delivery (PTD), 4.74% (3.76–5.73). The percentages of early and late neonatal deaths and PTD were significantly higher (p < 0.01) in primigravid compared to multigravid women. In primigravidae, 3.1, 1.1 and 7.1% of pregnancies resulted in early neonatal death, late neonatal death and PTD, respectively, while these outcomes in multigravidae were 1.0, 0.1 and 2.7%, respectively. Major malformations were identified in 4 newborns. Conclusions Low gravidity and young age predict perinatal death and PTD. The information collected here can be used as a baseline for adverse pregnancy outcomes in future vaccine trials in pregnant women.
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Affiliation(s)
- Naissem Andemel
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Santara Gaoussou
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Amadou Barry
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Djibrilla Issiaka
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Almahamoudou Mahamar
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Moussa Traore
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Alassane Dicko
- Malaria Research & Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Sciences Techniques and Technologies of Bamako, P.O Box 1805, Bamako, Mali
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
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Progress towards vaccines to protect pregnant women from malaria. EBioMedicine 2019; 42:12-13. [PMID: 30904605 PMCID: PMC6491615 DOI: 10.1016/j.ebiom.2019.03.042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 03/15/2019] [Indexed: 11/21/2022] Open
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