[A study of the efficacy of the chemoprevention of malaria using chlorproguanil alone or in combination with chloroquine in French expatriates in Dar-es-Salaam, Tanzania].

Seventy-nine French residents in Dar-es-Salaam, Tanzania, on 3 chemoprophylactic regimens, were included in a prospective study for a mean time of 10.8 +/- 3 months. No malaria attack was observed in the group (n = 32) taking chlorproguanil and chloroquine for chemoprophylaxis. Two attacks were reported in the group (n = 29) using chlorproguanil alone and 5 attacks in the group (n = 20) that was not taking antimalarial chemoprophylaxis. The blood concentration of chlorproguanil and chlorcycloguanil, the active metabolite, were measured, 3 hours (II3), 3 days (D3), and 7 days (D7) after the weekly dose. The urine concentration was measured at D7. The prophylaxis failure with chlorproguanil can be explained either by irregular use of the drug, or insufficiently lasting plasma concentration of chlorcyloguanil, or existence of parasite resistance to dihydrofolate reductase inhibitors.