STUDY ON THE DISTRIBUTION OF ONCHOCERCIAS IS AND LOIASIS IN WEST PROVINCE, CAMEROON

A clinical and parasitological survey of onchocerciasis and loiasis ha s been carried out in 38 communities in the West Province of Cameroon prior to the implementation of a mass ivermectin treatment. The highes t endemicity levels of onchocerciasis were recorded in the villages lo cated at an altitude below 1 400 m, and whose inhabitants go down to t he valleys for agricultural activities. Conversely low endemicity leve ls were recorded in the most populated part of the study area, which i s located at an altitude above 1 400 m, in the latter communities, the residents cultivate the high ground not far from their houses and are thus less exposed to transmission of onchocerciasis. Despite relative ly low microfilarial loads, the prevalences of nodules were fairly hig h; this demonstrates that in some epidemiological situations the latte r indicator gives an erroneous indication of the intensity of infectio n in the population. The prevalence of loiasis is very low in most of the villages of the study area.