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Adults in the small intestine of man release eggs that are evacuated with feces. The miracidium that hatches from the egg must penetrate a suitable snail in a very short time or it will die. This usually occurs within 5 - 52 hours. Cercariae develop from rediae that have metamorphosed from the miracidium. These cercariae swim and crawl their way to vegetation in stagnant water along river banks in endemic areas. There they encyst on these water plants becoming a metacercaria. It is the metacercaria that man ingests when consuming raw aquatic vegetation. The developing worm attaches itself to intestinal mucosa where it completes its life cycle.
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