[Evaluation of the drift of cercariae by a single daily sampling in the site of schistosomiasis transmission. Example of Guadeloupean sites of Schistosoma mansoni transmission (author's transl)].

Research on cercarian density in running water transmission sites of intestinal schistosomiasis in Guadeloupe has allowed the construction of a representative model of the rhythm of presence of Schistosoma mansoni cercariae. This model allows, with a single daily sampling between 11 a.m. and 2 p.m., the evaluation of the daily sum of hourly densities. We propose to measure the parasite component of the risk of contamination in a bilharzial site by the drift of cercariae expressed in cercariae/day. The drift of cercariae takes account of variations in cercarian density and of the flow of the channel. It expresses the daily quantity of cercariae available for human contamination.