Onchocerciasis and its control : report of a WHO Expert Committee on Onchocerciasis Control

Abstract

A comprehensive review of recent advances in knowledge about onchocerciasis and the methods for its control. Both research advances and practical lessons from the field are considered. Forward-looking in its approach, the report aims to identify measures that can accelerate control activities and increase large-scale ivermectin distribution to all communities at risk in the endemic zones. Attention is also given to the need to ensure that control activities are sustained and have acceptable cost-benefit ratios. The report has 13 sections. The opening sections summarize current knowledge of the filarial parasite Onchocerca volvulus and the blackfly vectors. Five sections profile current knowledge about the disease in terms of its clinical features, including changes following treatment with ivermectin, its geographical distribution and public health importance, its socioeconomic impact, and the measures available for diagnosis, surveillance, and treatment. Subsequent sections provide detailed discussions of the two main strategies for onchocerciasis control: chemotherapy with ivermectin and vector suppression through insecticide application and environmental management. Training requirements for integrated control are also identified. The remaining sections point out the need for sustainable programmes for ivermectin distribution and for monitoring and evaluation in order to ensure that control activities continue, that all onchocerciasis sufferers are reached, and that available resources are used efficiently. Annexed to the report is a clinical classification and grading system for recording the cutaneous changes of onchocerciasis