Whither onchocerciasis control in Africa? [editorial]

Infection with the vector-borne filarial parasite Onchocerca volvulus causes chronic skin and eye lesions often progressing to blindness and imposes an immense burden on affected populations. Most of those who have or are at risk of this infection are African. The discovery by Merck & Company (Rahway NJ) of ivermectin as an effective oral treatment of the disease and their unprecedented donation of hundreds of millions of doses of Mectizan since 1987 have revolutionized the assault on this scourge. This article discusses options for securing what has been gained so far. In west Africa the highly successful 30 year-old Onchocerciasis Control Program (OCP) which was first based on aerial spraying in savannah areas of 11 disease-endemic countries and later added mass drug administration (MDA) in savannah and forest areas ended in December 2002. Launched in 1974 the OCP has broken transmission in most of its target area and prevented more than 200000 cases of blindness at a cost of approximately U.S. $556 million. (excerpt)