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Medical Term:


Pronunciation: fluk

Definition: Common name for members of the class Trematoda (phylum Platyhelminthes). All flukes of mammals (subclass Digenea) are internal parasites in the adult stage and are characterized by complex digenetic life cycles involving a snail initial host, in which larval multiplication occurs, and the release of swimming larvae (cercariae), which directly penetrate the skin of the final host (as in schistosomes), encyst on vegetation (as in Fasciola), or encyst in or on another intermediate host (as in Clonorchis and other fish-borne flukes). Flukes of lower vertebrates (order Monogenea), especially fish, are frequently monogenetic ectoparasites or gill parasites. Blood flukes live in the mesenteric-portal bloodstream and associated vesical and pelvic venous plexuses; they include Schistosoma haematobium (the vesical blood fluke), S. mansoni (Manson intestinal blood fluke), and S. japonicum (the Oriental blood fluke). Other important flukes are Paragonimus westermani (bronchial or lung fluke), Opisthorchis felineus (cat liver fluke), Clonorchis sinensis (Chinese liver or Oriental fluke), Heterophyes heterophyes (Egyptian or small intestinal fluke), Fasciolopsis buski (large intestinal fluke), Dicrocoelium dendriticum (lancet fluke), Fasciola hepatica (liver or sheep liver fluke), and Paramphistomum (rumen fluke).

[A.S. floc, flatfish]

© Copyright 2016 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.