Schistosomiasis in travelers and immigrants.

Schistosomiasis is caused by trematode parasites of one of five species, Schistosoma mansoni, Schistosoma haematobium, Schistosoma japonicum, Schistosoma intercalatum, or Schistosoma mekongi, acquired via skin contact with fresh water containing infectious larval cercariae. Between 1 and 8 weeks after exposure, acute schistosomiasis presents as dermatitis, fever, fatigue, or eosinophilia. If untreated, long-term infection may cause anemia or undernutrition and may progress to liver fibrosis, portal hypertension, or hydronephrosis. Schistosomiasis represents a threat to residents and visitors in all endemic areas of Africa, Asia, and South America. Travelers should be made aware of infection risk if they become exposed to untreated fresh water. New immigrants and those returning to high-risk areas to visit friends and family should be screened for signs and symptoms of acute and chronic schistosomiasis. Physicians caring for travelers and immigrants must be familiar with the signs and symptoms of schistosomiasis and must be able to diagnose and treat it correctly.