Comparison of immunity to malaria in Sudan and Indonesia: Crisis-form versus merozoite-invasion inhibition

Plasmodium falciparum, human, comparison of populations from Flores, Indonesia, vs. southern Sudan in relation to splenomegaly, anti-plasmodium indirect fluorescent antibody titers, and ability of sera to either induce crisis-forms or inhibit merozoite invasion of erythrocytes, results suggest that immunity to malaria in Sudan is based on cell-mediated immune mechanisms associated with crisis forms and malaria immunity in Flores appears to be principally based on anti-merozoite antibody which does not cause crisis forms