Symptoms and effects of Oncherciasis
Onchocerciasis symptoms are caused by the Onchocerca volvulus larvae which migrate throughout the body, and upon their death they release certain toxins which cause inflammatory response; and subsequently the symptoms we associate with the disease. As with most diseases, the symptoms of Onchocerciasis differ slightly from person to person – in fact some of the infected experience no symptoms at all, although this is uncommon. The symptoms of Onchocerciasis can be divided into two categories – dermal (skin) and optic (eyes). Although not a fatal disease, symptoms can become very severe and debilitating without treatment.
There are many varying symptoms relating to the skin all of which begin with visible nodules, signifying the home of an adult worm. These are recognised as medium sized protruding lumps from the tissue underneath the skin, and are usually not painful. These protuberances are found predominantly over bony areas such as the hip, pelvis, ribs, shoulder blades, and skull. The skin then begins to become inflamed and slightly swollen, followed by intense itching which continues incessantly. This constant itching will usually lead to skin breakage and possible bacterial infection. If not treated, skin conditions will continue to worsen – severe dermatitis will occur. The skin becomes rough, scarred, thin and begins droop because of a loss in elasticity, giving an appearance of early aging. Finally, the skin will begin to lose its pigment giving a “leopard appearance”. These dermal symptoms can occur anywhere, but most commonly on legs and arms.
After many years of skin damage, visual problems will begin to occur – this general symptom is what gave Onchocerciasis its common name “river blindness”. Because eye lesions only occur after many years of severe infection, they are usually not present in people under the age of 30. The inflammation caused by larvae that die in the eye results in small opaque spots on the cornea. These spots are often accompanied by redness of the conjunctiva and result in vision loss (particularly peripheral vision). At a later stage, the cornea becomes permanently cloudy, which results in blindness. In Africa, visual imparity affects up to 80% of the infected, with 50% being completely blinded. Worldwide, Onchocerciasis is second only to trachoma as an infectious and preventable cause of blindness.
The effects of Onchocerciasis are very severe, especially from a socio-economic aspect. Although not directly fatal, blindness and skin disease caused by Onchocerciasis negatively affect a person’s ability to perform daily tasks, care for themselves and tend to their land. This means that without treatment, they would find it very difficult to source an income or provide food for their family. People with the disease often experience social isolation due to their infection as well.
People living around areas widespread with blackfly and infected humans are also impacted. Rural villagers often flee their fertile river valleys to settle in less productive upland country in fear of blindness, reducing agricultural productivity and increasing poverty. This justifies why it is so important that a vaccine is discovered in the near future for those infected with Onchocerciasis.
There are many varying symptoms relating to the skin all of which begin with visible nodules, signifying the home of an adult worm. These are recognised as medium sized protruding lumps from the tissue underneath the skin, and are usually not painful. These protuberances are found predominantly over bony areas such as the hip, pelvis, ribs, shoulder blades, and skull. The skin then begins to become inflamed and slightly swollen, followed by intense itching which continues incessantly. This constant itching will usually lead to skin breakage and possible bacterial infection. If not treated, skin conditions will continue to worsen – severe dermatitis will occur. The skin becomes rough, scarred, thin and begins droop because of a loss in elasticity, giving an appearance of early aging. Finally, the skin will begin to lose its pigment giving a “leopard appearance”. These dermal symptoms can occur anywhere, but most commonly on legs and arms.
After many years of skin damage, visual problems will begin to occur – this general symptom is what gave Onchocerciasis its common name “river blindness”. Because eye lesions only occur after many years of severe infection, they are usually not present in people under the age of 30. The inflammation caused by larvae that die in the eye results in small opaque spots on the cornea. These spots are often accompanied by redness of the conjunctiva and result in vision loss (particularly peripheral vision). At a later stage, the cornea becomes permanently cloudy, which results in blindness. In Africa, visual imparity affects up to 80% of the infected, with 50% being completely blinded. Worldwide, Onchocerciasis is second only to trachoma as an infectious and preventable cause of blindness.
The effects of Onchocerciasis are very severe, especially from a socio-economic aspect. Although not directly fatal, blindness and skin disease caused by Onchocerciasis negatively affect a person’s ability to perform daily tasks, care for themselves and tend to their land. This means that without treatment, they would find it very difficult to source an income or provide food for their family. People with the disease often experience social isolation due to their infection as well.
People living around areas widespread with blackfly and infected humans are also impacted. Rural villagers often flee their fertile river valleys to settle in less productive upland country in fear of blindness, reducing agricultural productivity and increasing poverty. This justifies why it is so important that a vaccine is discovered in the near future for those infected with Onchocerciasis.
Picture showing an infected persons skin - a loss of pigmentation and elasticity, as well as swollen fingers
Picture showing a person suffering from sever loss of vision or blindness due to Onchocerciasis