Infection by Onchocerca Volvulus.Encyclopedia Entry for Onchocerciasis :Onchocerciasis (river blindness): Onchocerciasis is caused by the larvae of Onchocerca volvulus, a parasitic worm that lives in the human body for years. It is endemic in Africa, where nearly all of the 18 million people infected with the disease live. Of those infected, over 6.5 million have developed dermatitis and 270,000 have gone blind. Symptoms include visual impairment, rashes, lesions, intense itching, skin depigmentation, and lymphadenitis.Encyclopedia Entry for Onchocerciasis :Onchocerciasis (River blindness). Source of disease: Onchocerca volvulus