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What is Giardia?

Giardia is a tiny parasite (an organism that feeds off of another to survive) that can cause a bowel infection. It’s in soil, food, or water that has been contaminated with feces (poop) from infected humans or animals. When a person gets sick, the infection is called giardiasis, or 'beaver fever'.

What are the symptoms?

Giardia affects children differently. Some have no symptoms, while others may have:

  • diarrhea or mushy bowel movements (which may have a very bad smell),
  • stomach cramps or nausea,
  • gas,
  • loss of appetite,
  • dehydration, and/or
  • weight loss.

The symptoms can last from 2 to 6 weeks.

How does it spread?

Giardia is spread when someone comes into contact with the parasite. For example:

  • A child swallows water while swimming or playing where Giardia may live, especially in natural outdoor water sources such as lakes, rivers, springs, ponds, and streams.
  • Germs from a dirty diaper, the toilet flush handle or the bathroom door handle can get on a person’s hands and spread into someone’s mouth.
  • From eating food that that hasn’t been washed or cooked properly.

How do you prevent Giardia?

  • Wash your hands with soap and water after changing a diaper, helping your child to go to the toilet or going to the toilet yourself.
  • Wash your hands before preparing and eating food.
  • Teach your child not to drink the water he swims in.

How do you treat it?

The Giardia parasite may be in a child's stool and not cause illness. If your child has no symptoms, treatment is not necessary.

If your child has symptoms, your doctor will ask you to provide a stool sample. It can be hard to detect Giardia so you may have to provide more than one sample.

If your child has Giardia, your doctor will prescribe a medication.  Your child should take all of the medicine prescribed by your doctor. If she stops taking it before the illness is gone, the infection can come back.

What can parents do?

  • Contact your doctor if you think your child has a Giardia infection.
  • Provide the stool samples on different days to confirm the diagnosis.
  • Continue to offer breast milk, formula or regular foods and liquids in small, frequent feedings, even if your child is vomiting.
  • If your doctor confirms that your child has Giardia, keep him home from child care until the diarrhea has stopped.
  • Make sure that everyone in your house is washing their hands with soap and water after changing a diaper and using the toilet, and before preparing and eating food.

Call your doctor if your child:

  • is vomiting and showing any sign of dehydration, such as
    • no tears when crying,
    • dry skin, mouth and tongue,
    • no or less urine (pee) (fewer than 4 wet diapers in 24 hours),
  • has a fever and is less than 6 months old or has had a fever for more than 72 hours,
  • is breathing rapidly,
  • has severe belly pain,
  • has severe diarrhea, or
  • has bloody or black stools.

Source: Well Beings: A Guide to Health in Child Care (3rd edition)

Reviewed by the following CPS committees:
Public Education Advisory Committee

Last Updated: November 2012