The Human Blood Fluke – Schistosoma mansoni
Schistosomiasis is a tropical parasitic disease that is transmitted from mammals to snails and then back to mammals. It is most prevalent in areas where sanitation is poor.
When human urine or feces containing schistosome eggs enters a body of water that harbors the appropriate snail intermediate host, the snail can become infected. After an incubation period the snail releases cercariae that can penetrate the skin of humans in the water.
The cercaria penetrates the skin, enters the bloodstream, and travels to the liver. In the liver, the schistosome worms wait to pair up as male and female, with the larger male clasping the female with his body.
Mouse over an image for a description of the S. mansoni life cycle stage. Click on an image to begin an exploration.
Cercaria Body and Ventral Sucker
Cercaria is the life cycle stage released from the snail. View the cercaria body and ventral sucker.
Cercaria Tail
Cercaria is the life cycle stage released from the snail. View the cercaria tail.
Schistosoma mansoni Eggs
S. mansoni eggs are excreted from the mammalian host.
Adult Male Schistosoma mansoni
The adult Schistosoma mansoni resides in the bloodstream of the mammalian gut. View the S. mansoni anterior sucker.