Giardiasis is an intestinal disease of
dogs, cats, and other animals that can be contagious to people. It is
caused by a protozoan called Giardia lambia. Infection occurs when a dog
or cat ingests giardial cysts in food, feces, soil, and most
importantly, contaminated water.
The most common sign of
giardiasis is diarrhea. It may be chronic or intermittent and may
contain mucus or blood. Other symptoms include weight loss,
listlessness, intestinal gas, or loss of appetite. Some animals may
carry giardia, show no clinical signs, but be infective to people and
A diagnosis of
giardiasis is made by examining a fresh fecal sample under a microscope.
Because shedding is intermittent, repeated microscopic examinations of
multiple stools may be required to find the cysts. Recent studies have
shown 30-60% of dogs and cats are infected.
Giardia is the most
common intestinal parasite in people. Good personal hygiene, i.e.
handwashing, should be practiced in homes where giardiasis has been
diagnosed in a pet.
water supply can contain giardia because chlorination does not kill it.
It is easily spread by wildlife (squirrels, raccoons, etc.). We
recommend treating all animals yearly for giardiasis, even if no
clinical symptoms are noted. Treatment with Panacur (fenbendazole) for
five days is the method of choice. This will treat for other common
intestinal parasites as well.