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The Burden of Schistosomiasis (Schisto, Bilharzia, Snail Fever)

Urine and stool samples tested for schistosomiasis. CDC photo, Sonia Pelletreau

Urine and stool samples tested for schistosomiasis. CDC photo, Sonia Pelletreau

Schistosomiasis is an infectious disease caused by parasitic worms found in fresh water. Fresh water snails are also infected by this parasite during its life cycle, and humans that come into contact with fresh water that contains these snails are at risk for infection. Seven hundred million people are at risk in 74 countries, and 240 million are already infected. Schistosomiasis ranks second only to malaria as the most common parasitic disease, and is the most deadly NTD, killing an estimated 280,000 people each year in the African region alone.

The disease can start with blood in the urine or stool, anemia and problems with growth and development in children, and eventually become life-threatening due to health effects such as bladder cancer and kidney and liver problems. Children with long-term or repeat infections can suffer from anemia and malnutrition, which can contribute to lost days at school and serious learning disabilities. Efforts to control the disease include treating infected people with a drug called praziquantel (donated in part by Merck KGaA) and proper disposal of feces and urine.

More on: Schistosomiasis  


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