Schistosomiasis. View of the distended abdomen of a man suffering from intestinal schistosomiasis (bilharzia). His abdomen has swollen due to liver and spleen enlargement (hepatosplenomegaly). The disease is caused by flukes, Schistosoma mansoni in this case, whose larvae live inside freshwater snails. When mature, the larvae leave their host and enter the water. They can penetrate human skin in order to reach the bloodstream, where they grow into adult worms. The adults produce eggs causing an influenza-like disease as well as the symptoms seen here. The eggs, which are passed in the urine and faeces, may infect more freshwater. Drug treatment is effective. Photographed in Sudan.