اونکوسرکوزیس و کوری رودخانه ای
Onchocerciasis is the world's second leading infectious cause of blindness
Rarely life-threatening, the disease causes chronic suffering and severe disability. In Africa, it constitutes a serious obstacle to socioeconomic development. It is often called river blindness because of its most extreme manifestation and because the blackflies that transmit the disease abound in riverside areas, where they breed in fast-flowing waters. Fertile riverine areas are frequently abandoned for fear of the disease.
The disease is caused by Onchocerca volvulus. It is mostly found in Africa but also a few countries in Latin America. A parasitic worm, Onchocerca volvulus, of the amily filariidae, lives in the human body for up to 14 years. Rarely life-threatening, the disease causes chronic suffering and severe disability. The male is 2-3 cm long and the female is up to 60 cm long. The vector for this parasite is the blackfly.
Adult worms remain in subcutaneous nodules, limiting access to the host's immune system. Microfilariae, in contrast, are able to induce intense inflammatory responses, especially upon their death. Dying microfilariae have been recently discovered to release Wolbachia-derived antigens, triggering innate immune responses and producing the inflammation and its associated morbidity. Wolbachia species have been found to be endosymbionts of O. Volvulus adults and microfilariae and are thought to be the driving force behind most of O. Volvulus morbidity. Severity of illness is directly proportional to the number of microfilariae and the power of the resultant inflammatory response