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River Blindness (Onchocerciasis)

River Blindness (onchocerciasis), another neglected tropical disease. It is caused by a parasitic worm and transmitted by the bite of a black fly, which breeds near fast-flowing water (like the rivers where many communities get water for drinking, washing and bathing).

The fly bite passes worm larvae into your skin, the worms breed and spread around your body, and when they die your immune system causes inflammation, which can blind you if it happens in your eyes. Communities often flee infected areas, meaning they lose their homes and their access to water, which puts them at risk of other diseases.


Much progress has been made in fighting the disease in several countries through control of the blackfly, however, the disease can now also be treated with an annual dose of the drug ivermectine, Mectizan®, which also relieves the severe skin itching caused by the disease. Costing an unbelievable 7 cents per person to treat each year, a tablet is taken for 10-15 years to eliminate the risk of River Blindness.  However, the cost is prohibitive to most people in low income countries where the disease is prevalent.