Plasmodium falciparum, Antibodies, Nested case–control, Low and unstable malaria transmission, Highland, Clinical malaria, Arctic medicine. Tropical medicine, RC955-962, Infectious and parasitic diseases, RC109-216

Abstract Background Defining antibody correlates of protection against clinical malaria in areas of low and unstable transmission is challenging because of limited malaria cases in these areas. Additionally, clinical malaria affects both adults and children in areas of low and unstable transmission, but it is unclear whether antibody correlates of protection against malaria differ with age. Methods Blood samples were obtained from 5753 individuals in Kenyan highland area with low and seasonal malaria transmission in 2007 and recorded episodes of clinical malaria in this population from 2007 to 2017. Using a nested case–control study design, participants who developed clinical malaria (cases) were matched by age and village to those who did not (controls). Immunoglobulin (Ig)G, IgG1, IgG3, IgA and IgM responses to 16 Plasmodium falciparum antigens were compared in individuals