Abstract

In 1988, the Malaria Research Unit of the Madagascar Pasteur Institute settled an out-patients clinic in Manarintsoa, a village of the Highland Plateaux where epidemic malaria appeared recently. 2776 consultants presented between January and June. In addition, the 200 schoolchildren were examined thrice. For each individual, clinical examination and thick and thin blood smears were performed. In the out-patients, parasite rates were above 50% each month and in each age group; the mean parasite rate being 74%. Splenomegaly rates were above 60% in individuals less than 15 years of age, and around 20% in adults. In schoolchildren, parasite and splenomegaly rates are consistently above 50%. Gametocyte indexes were 7.5% and 7% in May and October, respectively. Plasmodium falciparum is the most encountered species (in 85% of the cases), but P. vivax and P. ovale are also present. P. malariae is very rare. Early diagnosis and adequate therapy were very effective against mortality. During the high transmission time, monthly mortality rates varied from 12% before our arrival to 0.66% after. The number of malaria attacks was estimated at 2 per man and per year. In this area of unstable malaria, presence of fever appears to be of poor predictive value of the malaria infection. Systematic chloroquine therapy of fevers would be adapted to only 43% of the cases.