Background malaria incidence and parasitemia during the three-dose RTS,S/AS01 vaccination series do not reduce magnitude of antibody response nor efficacy against the first case of malaria

BMC Infectious Diseases

Research

Varun Goel¹  Katerina Brandt¹  Paulin Essone²  Selidji Todagbe Agnandji³  Griffin J Bell⁴  Michael Emch⁵  Jonathan J Juliano⁶  Jeffrey A Bailey⁷  Karamoko Niare⁷  Musah Osei⁸  Kenneth Wiru⁸  Kwaku Poku Asante⁸  Stephaney Gyaase⁸  David Dosoo⁸  Anita Ghansah⁹  Benedicta Mensah⁹  Bright Adu⁹  Tisungane Mvalo^1,10 

[1]Carolina Population Center, University of North Carolina, 27599, Chapel Hill, NC, USA

[2]Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon

[3]Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon

[4]Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany

[5]Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, 27599, Chapel Hill, NC, USA

[6]Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, 27599, Chapel Hill, NC, USA

[7]Carolina Population Center, University of North Carolina, 27599, Chapel Hill, NC, USA

[8]Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, 27599, Chapel Hill, NC, USA

[9]Division of Infectious Diseases, School of Medicine, University of North Carolina, 27599, Chapel Hill, NC, USA

[10]Department of Pathology and Laboratory Medicine, Brown University, 02912, Providence, RI, USA

[11]Kintampo Health Research Centre, Kintampo, Ghana

[12]Noguchi Memorial Institute for Medical Research, University of Ghana, Legon, Ghana

[13]University of North Carolina Project, Lilongwe, Malawi

[14]Department of Pediatrics, School of Medicine, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA

关键词: Vaccine;    Africa;    Geographic information system;    GIS;    Immunology;    Delayed Malaria;    Rebound Malaria;   

DOI  :  10.1186/s12879-023-08699-7

 received in 2023-05-30, accepted in 2023-10-11,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundRTS,S/AS01 has been recommended by WHO for widespread implementation in medium to high malaria transmission settings. Previous analyses have noted lower vaccine efficacies in higher transmission settings, possibly due to the more rapid development of naturally acquired immunity in the control group.MethodsTo investigate a reduced immune response to vaccination as a potential mechanism behind lower efficacy in high transmission areas, we examine initial vaccine antibody (anti-CSP IgG) response and vaccine efficacy against the first case of malaria (to exclude the effect of naturally acquired immunity) using data from three study areas (Kintampo, Ghana; Lilongwe, Malawi; Lambaréné, Gabon) from the 2009–2014 phase III trial (NCT00866619). Our key exposures are parasitemia during the vaccination series and background malaria incidence. We calculate vaccine efficacy (one minus hazard ratio) using a cox-proportional hazards model and allowing for the time-varying effect of RTS,S/AS01.ResultsWe find that antibody responses to the primary three-dose vaccination series were higher in Ghana than in Malawi and Gabon, but that neither antibody levels nor vaccine efficacy against the first case of malaria varied by background incidence or parasitemia during the primary vaccination series.ConclusionsWe find that vaccine efficacy is unrelated to infections during vaccination. Contributing to a conflicting literature, our results suggest that vaccine efficacy is also unrelated to infections before vaccination, meaning that control-group immunity is likely a major reason for lower efficacy in high transmission settings, not reduced immune responses to RTS,S/AS01. This may be reassuring for implementation in high transmission settings, though further studies are needed.

【 授权许可】

CC BY   
© BioMed Central Ltd., part of Springer Nature 2023

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