ABSTRACT
Schistosomes are trematode blood flukes that require snail intermediate hosts living in water. Snails can be contaminated by the faeces or urine of infected people. The snails then release the infective stage (cercariae), which penetrate the skin of human hosts, passing to the circulation and finally settling in the portal vein, where they mature into adult worms. The adult male and female worms swim against the direction of the bloodstream to reach their final habitat either in the mesenteric plexus of veins (Schistosoma mansoni, Schistosoma japonicum) or in the vesical plexus of veins (Schistosoma haematobium).
