Schistosomiasis, also known as bilharzia, is a parasitic disease caused by Schistosoma species of flukes. Infection is usually acquired by bathing in infected water, the different species of parasite causing different manifestations. Infection of the bladder causes constriction, calcification, and secondary infection, and can predispose to bladder cancer. Another form leads to gastrointestinal tract disease with liver involvement. Antimony compounds are often effect in treatment.