Schistosoma

Schistosoma is a genus of trematodes, commonly known as blood flukes. They are parasitic flatworms responsible for a highly significant group of infections in humans termed schistosomiasis, which is considered by the World Health Organization as the second-most socioeconomically devastating parasitic disease (after malaria), with hundreds of millions infected worldwide.Adult flatworms parasitize blood capillaries of either the mesenteries or plexus of the bladder, depending on the infecting species. [Source: Wikipedia ]