OverviewOnchocerciasis is also known as river blindness. It is a disease caused by a parasitic worm called Onchocerca volvulus. It is transmitted through repeated bites by infected Simulium blackflies. Onchocerciasis can cause itchy bumps on the skin and visual impairment. People who are at risk of getting infected with this disease are those who live in areas with Simulium blackflies, and travellers who travel to these areas for an extended period of time. People who travel to these areas for less than 3 months are less likely to get infected. Treatment of onchocerciasis should be treated promptly to prevent long-term blindness and skin damage. Medications used in the treatment include ivermectin and doxycycline. Ivermectin is given as long as the person has eye or skin symptoms, or every 6 months until the Onchocerca volvulus worm dies. Doxycycline kills the Wolbachia bacteria on which the worms depend on to survive.