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Schistosomiasis

Schistosomiasis, or bilharzia, is a parasitic disease caused by trematode flatworms of the genus Schistosoma. Larval forms of the parasites, which are released by freshwater snails, penetrate the skin of people in the water.

In the body, the larvae develop into adult schistosomes, which live in the blood vessels. The females release eggs, some of which are passed out of the body in the urine or faeces. Others are trapped in body tissues, causing an immune reaction.

In urinary schistosomiasis, there is progressive damage to the bladder, ureters and kidneys. In intestinal schistosomiasis, there is progressive enlargement of the liver and spleen, intestinal damage, and hypertension of the abdominal blood vessels.

Control of schistosomiasis is based on drug treatment, snail control, improved sanitation and health education.


GENERAL INFORMATION

Fact sheet on schistosomiasis

WHO PROGRAMMES AND ACTIVITIES

Department of Neglected Tropical Diseases

Partners for Parasite Control (PPC)

SCHISTOSOMIASIS IN WHO REGIONS

Region of the Americas–PAHO

RELATED TOPICS

Tropical diseases

Vaccine research

TECHNICAL INFORMATION

Control and preventive chemotherapy

- More about schistosomiasis

PUBLICATIONS

Preventive chemotherapy in human helminthiasis [pdf 1.57 Mb]

A lively and healthy me: teacher's resource book [pdf 1.02Mb]

- More publications on schistosomiasis

STATISTICS

Preventive chemotherapy and transmission databank


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