Onchocerciasis, or River Blindness, is a neglected tropical disease (NTD) caused by the parasitic worm Onchocerca volvulus. It is transmitted through repeated bites by blackflies of the genus Simulium. The disease is called River Blindness because the blackfly that transmits the infection lives and breeds near fast-flowing streams and rivers and the infection can result in blindness. In addition to visual impairment or blindness, onchocerciasis causes skin disease, including nodules under the skin or debilitating itching. Worldwide onchocerciasis is second only to trachoma as an infectious cause of blindness.
Image: Left/Right: Blackflies, the vector of onchocerciasis. Center: Microfilariae of O. volvulus from a skin nodule of a patient from Zambia, stained with H&E. Image taken at 1000x oil magnification. Credit: WHO, DPDx, CDC
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- General Information Most common questions answered...
- Epidemiology & Risk Factors Who gets it and how...
- Biology Stages of parasite development...
- Disease Signs and symptoms of the disease...
- Diagnosis Tests for infection...
- Treatment Medication and steps to take...
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