Onchocerciasis, or River Blindness, is a neglected disease (NTD) caused by the parasitic worm Onchocerca volvulus. Up to 18 million people are infected, mostly in sub-Saharan Africa. The disease has almost been eliminated from South America. It is transmitted through repeated bites by blackflies of the genus Simulium. The disease is called River Blindness because the blackfly that transmits the infection lives and breeds near fast-flowing streams and rivers and the infection can result in blindness. In addition to visual impairment or blindness, onchocerciasis causes skin disease, including nodules under the skin or debilitating itching. Worldwide onchocerciasis is second only to trachoma as an infectious cause of blindness. The African Program for Onchocerciasis Control (APOC) is the division of the World Health Organization that administers the fight against River Blindness. It oversees the annual distributions of over 100 million doses of ivermectin (learn more on Wikipedia or the CDC website).