n. a genus of parasitic pear-shaped protozoa inhabiting the human small intestine. They have four pairs of *flagella, two nuclei, and two sucking discs used for attachment to the intestinal wall. Giardia is usually harmless but may occasionally cause diarrhoea (see giardiasis).
An intestinal tract infection caused by Giardia lamblia, a flagellate protozoa now common to much of the world. Brought in by hikers and the hoards of grazing cattle, wintering over in beavers, elk and moose, it is one of the few parasites to be encountered in the mountains and north country. It is not normally a very serious infection, but for some reason certain people experience great debility.... giardiasis
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