Onchocerca volvulus

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Related to Onchocerca volvulus: Wuchereria bancrofti, Mansonella ozzardi

On·cho·cer·ca vol·'vu·lus

the blinding nodular worm, a species that causes onchocerciasis.

Onchocerca volvulus

A species of Onchocerca, a parasitic worm that is transmitted to people by the bite of black flies of the genus Simulium. Tiny, threadlike offspring of the worm migrate to the skin and eyes and produce inflammatory reactions that result in skin swellings and river blindness. The inflammation produced by the parasites may be mediated by a bacterium, Wolbachia, which in turn infests the parasitic worm.
See also: Onchocerca


a genus of nematode parasites in the family Onchocercidae. They are important as causes of onchocercosis. Their life cycles depend on the carriage of larval microfilariae by a variety of insects, chiefly mosquitoes, black flies and midges (families Simuliidae and Ceratopogonidae). The microfilariae are found in the lymph and connective tissue spaces of the skin. Called also Wehrdikmansia.

Onchocerca armillata
the microfilariae are found in the skin of the hump, withers, neck, dewlap and umbilicus and the adults in the aorta of cattle, buffalo, sheep, goats and donkeys.
Onchocerca bohmi
see elaeophorabohmi.
Onchocerca cebei
found in nodules on the brisket and the lateral aspects of the hindlimbs of buffalo. Called also O. sweetae.
Onchocerca cervicalis
found in the ligamentum nuchae of the horse and mule. The microfilariae are commonest in the area of the linea alba. Etiologically related to the occurrence of fistulous withers, poll evil, equine conjunctivitis and possibly equine recurrent ophthalmitis.
Onchocerca cervipedis
found in the subcutaneous tissues of the neck and limbs of deer.
Onchocerca dukei
adults are found in nodules in subcutaneous and perimuscular sites in cattle, mostly in the thorax, abdomen, diaphragm and thighs.
Onchocerca flexuosa
occurs in deer.
Onchocerca garmsi
parasites of deer.
Onchocerca gibsoni
found in nodules under the skin of the brisket or the lateral aspect of the hindlimbs of Bos taurus and Bos indicus cattle.
Onchocerca gutturosa
found in cattle and buffalo in the ligamentum nuchae, on the scapular cartilage and in the hip, shoulder and stifle areas.
Onchocerca lienalis
found in the gastrosplenic ligament, on the capsule of the spleen and above the xiphisternum in cattle.
Onchocerca ochengi
found in cattle, in nodules in cutaneous and subcutaneous sites on the udder, scrotum and flanks.
Onchocerca raillieti
adult worms are found in the ligamentum nuchae, in subcutaneous cysts on the penis and in perimuscular connective tissue of donkeys.
Onchocerca reticulata
a parasite of horses, mules and donkeys. Adult worms are found in the connective tissue of flexor tendons and suspensory ligament of the fetlock, mostly in the forelimb.
Onchocerca rugosicauda
found in the subcutaneous fascia in the shoulders and back of roe deer.
Onchocerca sweetae
see O. cebei (above).
Onchocerca synceri
found in subcutaneous tissues in African buffalo.
Onchocerca tarsicola
a parasite of deer.
Onchocerca tubingensis
a parasite of deer.
Onchocerca volvulus
causes dermatitis and ocular disease in humans.
References in periodicals archive ?
Towards a recombinant antigen vaccine against Onchocerca volvulus.
The role of Onchocerca volvulus in the development of epilepsy in a rural area of Tanzania.
The tiny worm that causes river blindness, Onchocerca volvulus, is a classic parasite.
Bites from a blackfly carrying the microscopic worm Onchocerca volvulus transmit the disease known as river blindness.
Human onchocerciasis (river blindness) is a disease caused by a filarial nematode Onchocerca volvulus (1).
lupi nematode infestation in humans (8) and its biologic and pathogenic affinity with Onchocerca volvulus, the agent of river blindness, heightened the interest of D.
The flies transmit the immature, thread-like forms, or microfilariae, of the parasitic worm Onchocerca volvulus, which migrate through the skin and can eventually invade the eyes, causing blindness.
It has also emerged as the drug of choice for large-scale treatment of onchocerciasis caused by Onchocerca volvulus.
In the areas of Africa and Latin America nearest the equator, blackflies that breed in river water carry a parasite called Onchocerca volvulus from human to human.
Onchocerciasis (river blindness) is a terminally blinding disease caused by Onchocerca volvulus and it is transmitted by members of Simulium damnosum sensu lato in west Africa (1,2).
Characterisation of nuclear ribosomal DNA sequences from Onchocerca volvulus and Mansonella ozzardi (Nematoda: Filarioidea) and development of a PCR-based method for their detection in skin biopsies.
Five species of filarial parasites have been reported in Nigeria, namely Wuchereria bancrofti, Onchocerca volvulus, Loa loa, Mansonella perstans and M.