Giardiasis is a disease caused by Giardia spp., a  protozoan parasite Read the content of the note 1 . It causes digestive issues in animals. The parasite can survive from 4 days to 2 months in ambient air or water.

This is a zoonotic disease, which means that animals can transmit it to humans.

At-risk animals

Giardiasis affects cattle, horses, pigs, sheep, goats, dogs, cats and birds. 

Wild animals can also be infected.

Signs of the illness

Infected animals rarely show any symptoms.

Signs are particularly visible in young animals, for example diarrhea, weakness, fur in a poor state, and weight and appetite loss.

Protection and prevention

Several measures can help prevent this disease in animals and transmission to humans.

Wash your hands with soap after changing a baby’s diaper, touching an animal and handling food or kitchen utensils.

Promptly pick up animal droppings and dispose of domestic waste appropriately in order to not to attract wild animals This hyperlink will open in a new window..

Test your well water regularly and avoid drinking untreated water, such as water from lakes and streams.

Restrict access to contaminated areas. Clean them thoroughly, disinfect and dry them. You can use bleach.

The parasite that causes giardiasis is resistant to most disinfectants. Adding chlorine to drinking water or to swimming pools is not enough to kill it.

In humans

Humans can be contaminated by domestic or wild animals, especially beavers. Infected animals that do not show any symptoms can still transmit the disease.

Giardiasis can be diagnosed 3 to 24 days after contamination. Signs appear most frequently within 7 to 10 days.

Giardiasis can be transmitted through direct contact with sick people or animals, via the fecal-oral route. For example, you can contract the disease if you smoke after touching an infected animal. 

A person can also contract the disease by drinking untreated water or eating a vegetable from a garden fertilized with contaminated manure.

The parasite is also transmitted in areas polluted with excrement, such as a watercourse, grassland or garden.

People in good health generally do not show any symptoms. Visible symptoms include diarrhea, intestinal cramps, abdominal bloating and weight loss. The disease can last from several days to several weeks and reappear even after recovery. 

Last update: January 8, 2024


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