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Infection with flukes (trematodes) of the genus SCHISTOSOMA. Three species produce the most frequent clinical diseases: SCHISTOSOMA HAEMATOBIUM (endemic in Africa and the Middle East), SCHISTOSOMA MANSONI (in Egypt, northern and southern Africa, some West Indies islands, northern 2/3 of South America), and SCHISTOSOMA JAPONICUM (in Japan, China, the Philippines, Celebes, Thailand, Laos). Source: DECS/BIREME


Schistosomiasis is a chronic parasitic infection caused by worms. It is most common in rural and impoverished populations. In the Americas, the parasite species is Schistosoma mansoni, which is associated with intestinal schistosomiasis. The main risk factor for infection is exposure through household, work, or recreational activities in fresh water contaminated with faeces from infected humans. In the Region, for transmission to occur, Biomphalaria snails, the intermediate hosts of the parasite, must also be present in contaminated water. Children and adolescents are the populations most at risk. Chronic infection can result in anaemia, fibrosis of intestinal veins and the liver, spleen enlargement, and in serious cases, neurologic complications and death. Schistosomiasis claims the lives of children and adults in the Americas each year.

General information about this disease

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