River Blindness Onchocerciasis Causes Nodules, Itchy Skin, Impaired Vision Symptoms

River blindness, onchocerciasis for formal, is a chronic infectious disease caused by Onchocerca volvulus parasite worm. It is brought to you via a female blackfly bite, that breeds near swift flowing rivers.

Onchocerciasis is locally transmitted in certain parts of Africa, Yemen, Central America and South America. And because it usually takes several infected fly bites to develop symptoms, you’re less likely to be in river blindness peril while on a short trip into these areas.

How onchocerciasis is spread requires a blackfly to bite an infected individual who has active microfilariae in their system. It develops into larvae while in the fly and then the parasite infection larvae is passed on to you in a bite.

The larvae then forms a nodule under your skin as it develops into an adult, which takes a year or more. If any female worm in your nodule is mated, she’ll produce eggs that develop into microfilariae.

Subsequently, the microfilariae migrate out into your skin and eye tissue. And these microfilariae are what’s responsible for your infection symptoms.

But the microfilariae generated never goes beyond its embryonic level while in you, only in a fly does it mature into larvae. Because an adult Onchocerca volvulus can live in your skin nodule for many years, the process of reproducing microfilariae over and over creates your chronic health condition.

The only symptoms adult worms typically cause are skin nodules. However, the death of the previously migrated offspring may cause intense itchy skin. Or their demise may cause a variety skin and eye related symptoms, like:

These river blindness itchy skin and impaired vision symptoms are primarily caused by you body’s inflammatory response to dead or dying microfilariae.

The effects on your vision may be only mild impairment, i.e blurry vision, or total blindness. Early symptoms of river blindness eye involvement include:

Onchocerciasis is second to trachoma for infection causing blindness.

There’s no vaccine nor a drug available that’s capable of killing adult worms. Yet, nodules can be removed to decrease their number.

For now, the main form of drug treatment for onchocerciasis is ivermectin. It is administered in a single dose annually and it prevents the build up of microfilariae. This reduces the incidence of itchy skin, vision impairment and blindness symptoms.

Although ivermectin is not a river blindness cure, it sure beats any site devastation caused by inflammation symptoms of microfilariae.

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