By Jereaghogho Efeturi Ukusare
Carrying out its God’s given assignment around a fast flowing river is the blackfly from the genus Simulium. This type of blackfly is usually found near rivers and streams. The bite of the infected female blackfly injects into the human body or animal the larvae of the worm known as Onchocerca volvulus. It is from this worm that the disease gets its scientific name “Onchocerciasis”. This worm is a parasite. And because the fly that infects with this worm is found around rivers and streams, the disease is popularly called “River Blindness.”
Affecting approximately half a million people across sub saharan Aftica annually, in its early stages, an infected individual notices no symptoms. It could take up to a year for symptoms of this disease to appear and the infection to become apparent. Once the infection becomes severe, symptoms may include:
bumps under the skin
loss of skin elasticity, which can make skin appear thin and brittle
itching of the eyes
changes to skin pigmentation
loss of vision
In rare cases, you may also have swollen lymph glands. Obviously, this disease is “very blind.”
Adult worms can live for up to 10 to 15 years and produce millions of microfilariae within this period of time. Microfilariae are baby or larval worms. Symptoms appear when microfilariae die, so symptoms can continue to worsen the longer you are infected. The longer these organisms stay in you, the closer you are to blindness.
Several tests are currently in use in diagnosing onchocerciasis. The first thing the clinician does is to feel the skin to try to identify nodules. Your doctor will do a skin biopsy, known as a skin snip. During this procedure, they will remove a 2 to 5 milligram sample of the skin. The biopsy is then placed in a saline solution. This will make the larvae to emerge. Multiple snips, usually six are taken from different parts of the body. Other methods of diagnosis also exist.
The most common treatment for onchocerciasis is ivermectin (Stromectol). It is considered to be safe for most people and it is administered once or twice a year to be effective. It also does not require refrigeration.
Amazingly, there is currently no vaccine to prevent onchocerciasis. For most people, the risk of contracting onchocerciasis is low. Those at the highest risk are residents of certain regions of Africa and Latin America. The best way to keep away from being blind, that is, preventing the disease from getting to you is to avoid being bitten by blackflies when you find yourself in its territory. Wear long sleeves and pants during the day, use insect repellant and wear permethrin-treated clothing. Make sure to visit a doctor if you suspect an infection so you can begin treatment before symptoms become severe. Do not go blind. It is hard.