Epidemiology of filariases caused by L. loa and D. perstans in seven villages of the Central-Southern Province of Cameroon.

An epidemiological study of filariasis caused by Loa loa and D[ipetalonema] perstans was carried out in 1977 in 7 villages of the Central-Southern Province of Cameroon, 5 of which were situated in the Sanaga Valley in an area of concentrated breeding sites of Simulium damnosum Theo. [see RAE/B 66, 1492]; in general, the older inhabitants of these villages were more susceptible to filariasis than were the younger ones, but infected women had less severe filaraemia than infected men. Biting flies collected from human bait in the study area were S. damnosum, Chrysops dimidiatus Wulp, Culicoides trifasciellus Goetgh., C. kumbaensis Callot, Kremer, Mouchet & Bach and C. grahamii Aust. The ceratopogonids were active only in the hour after sunrise and the hour before sunset. Chrysops was found mainly in the forest near water, but some examples were caught in the centre of the villages.