Onchocerciasis is caused by infection with nematodes Onchocerca vulvulus. It has also long been associated with a high incidence of detrimental effects on socioeconomic development and public health in endemic areas due to the severe disabilities. Onchocerciasis is present in 19 districts of five regions in Tanzania approximately four million people at risk of infection and the disease is transmitted by the black fly Simulium damnosum. Prevalence can be as high as 63.6% in certain focal endemic areas and morbidity characteristically includes dermatologic, lymphatic, ophthalmologic, and systemic manifestations.