The Onchocerciasis Control Programme in West Africa (OCP) undertook regional and large scale frght against onchocerciasis in West Africa in 1974 using a vector control strategy. By 2002 OCP had succeeded in eliminating the disease as a public health, socio-economic and development problem in 10 out of I I countries. This campaign was highly technical and expensive. ln 1987, Merck & Co.,lnc. committed themselves to provide ivermectin free of charge for as long as needed to onchocerciasis endemic countries. This made it possible to envrsage the extension of onchocerciasis control activities to the remaining endemic countries in Africa.