Prophylaxis of malaria in the Sudan. With special reference to the use of plasmoquine

Abstract

Malaria is most prevalent in the Gezira between October and January, following a well-defined seasonal periodicity. All three types of infection occur, malignant tertian being most prevalent. The incidence of the disease follows the rainfall curve at an interval of approximately two months. The only infecting mosquito worth considering is Anopheles gambiæ which is most prolific from September till February and possibly æstivates during the summer months. Naturally infected mosquitoes never exceed 2 per cent. The human carrier of the disease is chiefly the child who is most heavily infected with gametocytes between October and January. Experiments have been carried out to test the efficacy of plasmoquine in causal and gametocyte prophylaxis. Small daily doses of the drug for causal prophylaxis are not recommended as they tend merely to conceal infection. The results of experiments in gametocyte prophylaxis tend to show that a biweekly dose of 0·02 gramme plasmoquine simplex to children might be of considerable value in antimalarial work. Conclusions drawn from the short period under review are suggested with diffidence.