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A parasitic disease
What is it?
Photo of GiardiaPhoto credit: CDC/ Janice Carr

Giardia is a single-celled, microscopic parasite that can live in the intestines of humans and animals. Found world-wide, over the past two decades Giardia infections have become one of the most common waterborne diseases for people in the United States.

How do I avoid it?

  • Wash your hands thoroughly with soap and water, especially after using the toilet, changing diapers or before handling or eating food.
  • Do not drink untreated water, including ice made from unsafe water.
  • When you can't avoid suspect water, boil it for at least one minute or use a filter rated for "cyst removal".
  • Wash and/or peel all raw vegetables and fruits before eating.

What are the symptoms?

A Giardia infection can cause a variety of intestinal symptoms, Including:

  • diarrhea
  • gas or flatulence
  • greasy stools that tend to float
  • stomach cramps
  • upset stomach or nausea
These symptoms may lead to weight loss and dehydration. However, some people with Giardia have no symptoms at all.

How do I get it?

Like other food- and waterborne diseases, Giardia spreads when poop contaminates:

  • Food
  • Water, including swimming pools, hot tubs, Jacuzzis, fountains, lakes, rivers, springs, ponds or streams
  • Surfaces such as bathroom fixtures, changing tables, diaper pails or toys
Accidentally putting something into your mouth that has come into contact with Giardia can lead to an infection.

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