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Infection with the filaria Onchocerca volvulus ; results in skin tumors, papular dermatitis, and ocular complications.



a chronic parasitic disease that is caused by nematodes of the genus Onchocerca. Onchocerciasis occurs universally and mainly affects ungulates; the greatest economic damage arises when cattle and horses are affected. The intermediate hosts of Onchocerca are simuliids and ceratopogonids, which are bloodsucking insects. The infestation is most prevalent in pastures during the swarming time of the intermediate hosts. The mature parasites concentrate in the tendons, ligaments, and connective tissue, causing inflammatory foci that are often aggravated by pyogenic microflora.

Onchocerciasis usually occurs without observable symptoms. Diagnosis in the living animal is based on the presence of Onchocerca larvae in skin biopsies and on the results of allergic skin tests. No specific treatment is available. Onchocerciasis is prevented by protecting animals from the bites of simuliids and ceratopogonids and by exterminating these insects during hatching time, from May to August.


Skriabin, K. I., and A. M. Petrov. Osnovy veterinarnoi nematodologii. Moscow, 1964.
References in periodicals archive ?
Human onchocerciasis in the Amazonian area of southern Venezuela: spatial and temporal variations in biting and parity rates of black fly (Diptera: Simuliidae) vectors.
volvulus strains exist, the differences in the epidemiological and clinical signs of onchocerciasis in the endemic regions had been attributed to these variations (6,11).
Ivermectin influence on the mast cell activity in nodules of onchocerciasis patients.
Although many surveys of NTDs have been conducted, the most detailed maps are for onchocerciasis, lymphatic filariasis, and schistosomiasis.
The State Ministry of Health of Gombe, which is located in northeastern Nigeria, Africa, in conjunction with Upper Benue River Basin Development Area office and local government, have taken measures to control the area's black flies, whose bite causes onchocerciasis or river blindness, the world's second leading cause of infectious blindness.
Roses also said PAHO is developing a list of diseases that could be eliminated or significantly reduced by 2015, including leprosy, trachoma, onchocerciasis, vector-borne Chagas' disease, lymphatic filariasis, and congenital syphilis.
Annual transmission potential (ATP): ATP proposed by Walsh et al (18), to evaluate the impact of Simulium control in reducing the transmission of onchocerciasis.
With its new 10-year strategy, the TDR--responsible over the last three decades for containing diseases such as leprosy, onchocerciasis (that causes river blindness), Changas disease, lymphatic filariasis, and visceral leishmaniasis--will confront the biggest challenges of the global health community: getting poor people access to primary health treatments.
This has helped in putting in place programmes geared towards the eradication of trachoma and onchocerciasis (river blindness), a major disease in nearby Ethiopia.
They include lymphatic filariasis or elephantiasis, which causes grossly enlarged legs and genitals, and onchocerciasis, better known as river blindness, a cause of skin disease and blindness.
A notable example is the Fund's involvement in the fight against Onchocerciasis, or River Blindness, a parasitic disease caused by the Filarial Worm and spread between people by the Black Fly which breeds in fast flowing rivers.