This disease affects mainly the eyes & skin. It's caused by worms transmitted through the bite of infected black flies.
ONCHOCERCIASIS is the 2nd leading infectious cause of blindness globally but many people know nothing about it.
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ONCHOCERCIASIS is the 2nd leading infectious cause of blindness globally but many people know nothing about it.
A thread 🧵
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The black fly which causes onchocerciasis breeds mainly in fast-flowing rivers & streams.
This happens mainly in remote villages in the tropics located near fertile lands where people rely heavily on farming or herding.
The black fly which causes onchocerciasis breeds mainly in fast-flowing rivers & streams.
This happens mainly in remote villages in the tropics located near fertile lands where people rely heavily on farming or herding.
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The female adult worms produce #larvae (microfilariae) that migrate to the skin, eyes & other organs.
One female worm can release up to 1000 larvae a day into surrounding tissue.
The worms can live up to 15 years in the human body enclosed in fibrous tissues called #nodules.
The female adult worms produce #larvae (microfilariae) that migrate to the skin, eyes & other organs.
One female worm can release up to 1000 larvae a day into surrounding tissue.
The worms can live up to 15 years in the human body enclosed in fibrous tissues called #nodules.
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When a female black fly bites an infected person during a blood meal, it also takes in the larvae.
These larvae then evolve into the infectious stage & are transmitted to the next human host during the next bite.
When a female black fly bites an infected person during a blood meal, it also takes in the larvae.
These larvae then evolve into the infectious stage & are transmitted to the next human host during the next bite.
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When the microfilarial worm dies, it induces inflammatory reactions that cause;
- intense itching
- bumps under the skin
- skin scarring
- skin swelling
- loss of skin elasticity (e.g. hanging groin)
- total loss of skin color (leopard skin) & sometimes
- total blindness
When the microfilarial worm dies, it induces inflammatory reactions that cause;
- intense itching
- bumps under the skin
- skin scarring
- skin swelling
- loss of skin elasticity (e.g. hanging groin)
- total loss of skin color (leopard skin) & sometimes
- total blindness
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Onchocerciasis can be treated with a drug called #ivermectin.
This drug paralysis the worms, reduces their production of more larvae, & reduces the itching & progression to blindness.
You must take this drug at least once yearly for 10-15 years for treatment to be complete.
Onchocerciasis can be treated with a drug called #ivermectin.
This drug paralysis the worms, reduces their production of more larvae, & reduces the itching & progression to blindness.
You must take this drug at least once yearly for 10-15 years for treatment to be complete.
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To prevent onchocerciasis, avoid black fly bites;
🔸use insecticides that contain DEET (diethylmetatoluamide) on exposed skin
🔸wear long sleeve shirts & trousers
🔸wear permethrin treated clothes
No vaccine or approved drug to prevent the disease, so avoid black fly bites
To prevent onchocerciasis, avoid black fly bites;
🔸use insecticides that contain DEET (diethylmetatoluamide) on exposed skin
🔸wear long sleeve shirts & trousers
🔸wear permethrin treated clothes
No vaccine or approved drug to prevent the disease, so avoid black fly bites
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