[The campaign against onchocerciasis in Africa: update]

Two methods are being used to control onchocerciasis. The first has a delayed effect and consists in reducing or interrupting transmission of Onchocerca volvulus by eradication of the vector at its most vulnerable developmental stage, i.e. the larval stage. The second method has more immediate effects and consists in mass treatment using ivermectin, the only widely available drug, to reduce the density of microfilariae (the pathogenic stage of the parasite) in the population. Both strategies have been implemented within the framework of two international programs: the Onchocerciasis Control Program (OCP) in West Africa, which started in 1974 and will continue until the end of 2002, and the African Program for Onchocerciasis Control (APOC), which was launched in 1995 and will last for 12 years. This article presents an overview of the efficacy of available control tools, as well as the objectives, strategies, organization, and results of the two ongoing control programs. Also dealt with are future perspectives of onchocerciasis control including monitoring techniques to maintain OCP gains, and research to develop new control tools and optimize the program efficacy.