Fig. 1 Life cycle of Schistosoma 1. Definitive host, 2. Schistosome eggs released in urine or faeces of definitive host, 3. Free-swimming miracidia from eggs, 4. Intermediate host, 5. Cercaria (penetrates skin, loses its tail and transforms into schistosomulum), 6. Paired adult worm (schistosomulum migrates to the hepatic portal system; adult worms mature in pairs in the veins surrounding the bladder, intestines or liver. They produced eggs, the majority of which are eliminated in urine or faeces of definitive host to the environment. The eggs hatch liberating miracidia to restart the life cycle. 71