What is the regional spread of onchocerciasis?

Eye and Skin. Onchocerciasis is an eye and skin disease. Symptoms are caused by the microfilariae, which move around the human body in the subcutaneous tissue and induce intense inflammatory responses, especially when they die. Infected people may have severe itching and various skin lesions. In most cases, nodules develop under the skin. Some may develop eye lesions which can lead visual impairment or blindnes.