metacercaria

fluke form

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Last updated

June 30, 2026

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A metacercaria is the late larval stage of a digenetic trematode (fluke) that is tailless and encysted. This form is typically what infects the definitive host. Many fluke species parasitize humans and animals, with some being ingested as cysts, known as metacercariae, in uncooked food. For example, the lung fluke Paragonimus westermani is found in crustaceans, while intestinal and liver flukes are ingested through contaminated fish or aquatic plants. The human and swine parasite Fasciolopsis buski is contracted by eating aquatic plants containing these encysted larvae.123

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flatworm
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…are ingested as cysts, called metacercariae, in uncooked food—e.g., the lung fluke Paragonimus westermani found in crayfish and crabs, the intestinal flukes Heterophyes heterophyes and Metagonimus yokogawai and the liver fluke Opisthorchis sinensis in fish, and the intestinal fluke Fasciolopsis buski on plants. Free-swimming larvae (called cercariae) of blood flukes…
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…are ingested as cysts, called metacercariae, in uncooked food—e.g., the lung fluke Paragonimus westermani found in crayfish and crabs, the intestinal flukes Heterophyes heterophyes and Metagonimus yokogawai and the liver fluke Opisthorchis sinensis in fish, and the intestinal fluke Fasciolopsis buski on plants. Free-swimming larvae (called cercariae) of blood flukes…
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