Simuliidae and their relation to human onchocerciasis in northern Venezuela.

A study of the vectors of onchocerciasis was carried out in 1961 in northern Venezuela at the request of the Venezuelan Government. This article, based on the report submitted, records various observations made-mainly during the dry season-on the identification and biology of the Simuliidae and on the possibilities of controlling them.Twelve Simulium forms were encountered; special attention was paid to the two common man-biting species; S. exiguum, which was abundant but of uncertain relation to onchocerciasis, and S. metallicum. The authors conclude that S. metallicum is the main or only vector in the area studied, but that S. exiguum might possibly also transmit onchocerciasis in certain places near large streams where it is found in great numbers.