[The value of malaria antibody level determination in non-immune subjects in a holoendemic area].

The use of indirect immunofluorescence in non-immune people under heavy risk of chloroquine resistant Plasmodium falciparum malaria has a fair interest for diagnosis because of atypical clinic features and poor parasite density in thin smears. Indirect immunofluorescence has been used in Cotonou where chloroquine resistant strains of Plasmodium falciparum was described since 1986. This lead to detect numerous cases of malaria with negative thin smear. Under epidemiological considerations, non-autochthonous people's antibody acquiring curve related to residence time in endemic area is parallel to the autochthonous children's antibody acquiring curve. However, average of antibody titer is strongly lesser in non-autochthonous population even after living more than 12 years in holoendemic area. This can reveal a lesser capacity to acquire immunity in non-autochthonous people due to a lesser exposure or to prophylaxis. This has to be pointed out when prophylactic strategies are proposed to those who live endemic areas. Authors propose to look back upon past obsolete prophylactic methods as repellents, insecticides, mosquito nets, air conditioned, etc.