Onchocerciasis or “river blindness” is a disease that is caused by an infection by Onchocerca volvulus- a type of parasitic roundworm. Onchocerciasis is the second-leading cause of blindness in the world that is caused by an infection. The worm carries a bacteria, Wolbachia pipientis, that causes severe inflammation. The body’s inflammatory response leaves many blind. The transmission of the bacteria is caused by the bite of a black fly, Simulium. The larval worms are spread throughout the body, and when they die the bacteria is released, triggering an immune system response that causes severe itching and can lead to the destruction of tissue in the eye.
In some countries, river blindness is effectively managed by spraying breeding sites of the blackfly with insecticides. There is also a drug available (ivermectin) that kills the microfilariae, reducing the severity of symptoms and transmission.
The first major effort to stop river blindness was the Onchocerciasis Control Programme, launched in 1974. At its height, the program covered 30 million people over eleven countries. It utilized larvacidal spraying of rivers and the usage of ivermectin. The program was a great success and was ended in 2002. The area is continually monitored to ensure that onchocerciasis cannot re-invade its former habitat.
The Onchocerciasis Elimination Programme for the Americas (OEPA) is another effort to combat river blindness. It is sponsored by the Carter Center- a non profit organization founded by former U.S. President Jimmy Carter in 1982. Based in Guatamala, The OEPA works towards ending the illness and transmission of river blindness in the six countries affected in Latin America.
Another major effort to combat river blindness is being undertaken by the African Programme for Onchocerciasis Control (APOC). Formed in 1995, it covers 19 African countries, mainly focusing on the use of the anti-parasitic medicine ivermectin.