Geographical distribution and seasonal variation of the vectors of Human Onchocerciasis in South East Nigeria

Abstract

The different bioecological zones in the Southeast of Nigeria were surveyed for the vectors of human Onchocerciasis, Simulium damnosum complex of blackflies. Three species were identified and these were S. damnosum, S. squamosum and S. yahense. One of the species, S. squamosum was found to consist of two chromosomal variant populations. The species distribution was assessed in relation to the different vegetation zones of the study area, topography, river size and other factors. The range of each species was influenced by seasonal climatic changes in wind movement, and river water level. S. damnosum and S. squamosum were recorded from all the bioclimatic zones although they were more frequently observed in the dry season samples than in the wet. S. yahense was found breeding in the mosaic forest and forest areas.

Journal of Biomedical Investigation Vol. 5 (1) 2007: pp. 27-36