River blindness is spread by repeated bites from infected black flies. It's most common in those who live in remote African villages. People who travel and volunteer in these areas also are at risk.
Symptoms may not appear for up to one to two years after infection. Skin sores, itching, and nodules may develop. Eye lesions can lead to vision changes and blindness.
Medication can kill the parasites.
Last Updated Jun 13, 2017