|
Schistosoma Species
- The schistosomes are also known as "blood-flukes".
- There are several important species producing serious human and animal disease in the tropics.
- The pathology is mostly associated with the passage of eggs through the liver, urinary bladder or intestinal wall (depending on the predilection site of the fluke).
- As their common name suggests, the adults live in blood-vessels.
- Unusually for a trematode, the sexes are separate.
- The smaller female lies enveloped by the male.
- The eggs of most species have spikes to assist their passage through host tissue to get into faeces or urine (depending on predilection site).
- The intermediate hosts are water snails.
- On release, the cercariae swim in water and actively seek their final host, which they enter by skin penetration - there is, therefore, no metacercaria stage.