ABSTRACT
The genus Onchocerca (Nemata: Onchocercidae) is comprised of species that are parasites of ungulates with the exception of O. volvulus, the etiological agent of human river blindness. Onchocerciasis is distributed mainly in subSaharan Africa with smaller foci in Yemen and the Americas. It has three different pathologies, dermal, lymphatic, and ocular, but there are differences in the clinical manifestations depending on the geographical region. Thus, in West Africa, levels of blindness are higher in the savannah than in the forest. This has been explained by the existence of two differentiated strains. It is estimated that approximately 17 million people are affected, of which 500,000 are visually impaired and 270,000 blind. Given the relevance of onchocerciasis, the World Health Organization has put in place different control programs to eradicate the disease. This has led to a wealth of methods for the detection of infection and even for the differentiation between the two West African strains. This chapter introduces these parasites to the reader and describes some of the DNA-based methods used for the detection of onchocerciasis.
