A RAPID MAPPING TECHNIQUE FOR THE PREVALENCE AND DISTRIBUTION OF ONCHOCERCIASIS - A CAMEROON CASE-STUDY

A rapid and cheap method for mapping the endemicity levels of onchocer ciasis in both forest and savanna areas, where the vectors are members of the Simulium damnosum complex, is described. The selection of the study communities is based on a general understanding of the vectors' ecology and biassed towards those at highest risk of onchocerciasis, a lthough there must be adequate geographical coverage. In a case study in Cameroon, prevalences were determined, using the non-invasive nodul e palpation technique, in samples, each of 30-50 adult males, from 49 villages in six study areas in Cameroon. The method proved effective i n the rapid mapping of onchocerciasis distribution in all areas studie d, in which the distribution patterns varied from the classical linear to diffuse, and in one area with an anomalous distribution. The metho d should prove of value in the design of national onchocerciasis contr ol programmes.