NCIt definition : A disease caused by infection with Onchocerca volvulus; symptoms may include pruritis
and blindness.;
Alternative definition : NICHD: An infection that is caused by the nematode Onchocerca volvulus, which most
commonly occurs in tropical climates, and which is transmitted by bites from a black
fly. Symptoms include intense pruritus, inflammation, and swelling of skin; if the
larvae migrate to the eye, blindness can occur.;