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Giardia Parasite
The Giardia parasite is a single-celled microscopic organism that causes giardiasis, a diarrheal illness. It lives in the intestine of infected humans and animals, and is transmitted through accidental ingestion.
The parasite can be found in numerous places, including:
- Food
- Water
- Soil
- Surfaces that have been contaminated with feces from infected humans or animals.
The most common methods of Giardia parasite transmission is by:
- Accidentally putting something into your mouth or swallowing something that has come into contact with the feces of a person or animal infected with the parasite
- Accidentally swallowing the Giardia parasite picked up from surfaces (such as bathroom fixtures, changing tables, diaper pails, or toys) contaminated with feces from an infected person
- Eating uncooked food contaminated with the Giardia parasite.
(Click Giardia Lamblia for a more in-depth look at the Giardia parasite, including a detailed diagram and information on the parasite's life cycle.)
Written by/reviewed by: Arthur Schoenstadt, MD
Last reviewed by: Arthur Schoenstadt, MD



