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== ''Schistosoma'' Species ==
 
== ''Schistosoma'' Species ==
*The schistosomes are also known as "blood-flukes".
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*The schistosomes are also known as "blood-flukes"
*There are several important species producing serious human and animal disease in the tropics.
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*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).
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*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.
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*As their common name suggests, the adults live in blood vessels
*Unusually for a trematode, the sexes are separate.
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*Unusually for a trematode, the sexes are separate
*The smaller female lies enveloped by the male.
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*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).
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*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.
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*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.
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*On release, the cercariae swim in water and actively seek their final host, which they enter by skin penetration
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**There is therefore no metacercaria stage
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