Onchocerciasis is an insect-borne disease caused by a parasite Onchocerca volvulus and transmitted by blackflies of the species Simulium damnosum. Onchocerciasis is often called "river blindness" because the blackfly which transmits the disease abounds in fertile riverside areas, that frequently remain uninhabited for fear of infection. O. volvulus is almost exclusively a parasite of man. Adult worms live in nodules in a human body where the female worms produce high numbers of first-stage larvae known as microfilariae. They migrate from the nodules to the sub-epidermal layer of the skin where they can be ingested by blackflies. They further develop in the body of the insect from which more people can be infected. Eye lesions in humans are caused by microfilariae. They can be found in all internal tissues of the eye - except the lens - where they cause eye inflammation, bleeding, and other complications that ultimately lead to blindness.
In the early 1970s, seven West African countries beset by drought and food shortages: Benin, Togo, Ghana, Burkina Faso, Mali, Niger and the Cote d'lvoire, joined together to appeal for help. They approached a number of organisations, one of the more important being the World Bank, whose president was Robert McNamara. Flying over six West African countries, McNamara remarked to one of his companions that there seemed to be large areas of presumably fertile land beside the rivers which remained uncultivated. Couldn't this produce more food? he asked. He was told that the riverine land had been abandoned: the people had fled the scourge of river blindness. "The worst thing about it - this sounds brutal is that it doesn't kill", said McNamara. "Some commit suicide as the bites are so irritating, and some go blind. I saw in these very primitive African villages adults, male and female, being led around at the end of a stick, because they weren't dead, they had to be fed, but they couldn't contribute to life it was a horrible situation."
At that time river blindness or onchocerciasis, to
give it its medical name affected over one million people in
The Onchocerciasis Control Programme (OCP) was set up in 1974 with the World Health Organisation as the executive authority. It spanned eleven affected countries. The programme adopted a two-prong approach: while the search continued for a cure for the disease, an operation of military precision was mounted against the infected blackfly.
Information on Onchocersiasis on the WHO website.