Intrinsic individual differences in circumsporozoite antibody response at a hyperendemic malaria focus

Antibody to the repetitive domain of the Plasmodium falciparum circumsporozoite (CS) protein was measured in blood collected over 3 consecutive months from 224 residents of a hyperendemic focus in Thailand. An enzyme-linked immunosorbent assay incorporating the protein ([NANP]15 + NVDP)2 was used. More than 22% of adults produced high antibody titres in all 3 months, even though transmission had stopped. Malaria prevalence in these high-responders was the same as in the rest of the population and the number of consanguineous high-responders was no higher than would be expected by chance. The data suggest that individuals at prolonged, equal risk of malaria inoculation display intrinsic differences in their ability to produce CS antibody.