The adult worms that cause this disease can live in the human body for up to 15 years and the disease is the second leading infectious cause of blindness in the world
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Name
River blindness, aka onchocerciasis (the name comes from the fact that people are infected by flies that live in rivers and the disease can cause blindness)
Transmission
- An eye and skin disease caused by parasitic worms called Onchocerca volvulus
- The parasites enter the human body through the repeated bites of black flies infected with the worms
- These flies breed in fast-flowing rivers and streams
- To get the disease, people often need to be bitten more than once by the infected flies
Geography
Mainly sub-Saharan Africa (30 countries) but also Latin America (6 countries) and Yemen
Incubation Period
Ranges from 9 – 24 months after the infected bite(s)
Signs and Symptoms
- Skin rashes
- Severe itching
- Skin lesions
- Loss of skin elasticity
- Change in skin pigmentation (known as leopard skin in the lower legs)
- Skin nodules
- Eye lesions
- Visual impairment
- Blindness
Diagnosis
Skin biopsies, eye exams, and antibody tests are usual methods to diagnose river blindness
Treatment
- The medicine ivermectin is available, but only kills the worm larvae, not the adult worms
- The medicine needs to be given every 6 months for the life span of the adult worms or for as long as the infected person has evidence of skin or eye infection
- The World Health Organization suggests using ivermectin at least once a year for 10 to 15 years to complete the treatment
- Another treatment option is to use the antibiotic doxycycline to kill the bacteria in the body called Wolbachia which the adult worms need to survive
Prognosis
- With long-term treatment, river blindness is curable
Prevention: What Can You Do?
- There are no vaccines or medications for prevention
- Reduce your exposure to biting insects (wear long clothing, use insect repellant, etc.)
River Blindness In the News
- Uganda scores major victory against river blindness, nears eradication
- How Worm Warriors Are Beating An Unbeatable Worm
Sources:
http://www.who.int/onchocerciasis/en/
http://www.cdc.gov/parasites/onchocerciasis/
