Giardia Worm in Cats

Giardia is not an actual worm but a one-celled organism that infects the small intestines of cats and dogs. These infections by the protozoa are still being studied, as the organisms are not yet well understood.

  1. Transmission

    • Cats get giardia by ingesting the organism during the cyst form of its lifecycle. Usually this comes from drinking water contaminated with the protozoa.

    Symptoms

    • Many cats will show no symptoms that they are infected with giardia. However, in kittens, an infection can cause severe diarrhea and weight loss.

    Diagnosis

    • Giardia is difficult to diagnose. Many times veterinarians must test stool samples for a few days before being able to find the organism under a microscope. Sometimes veterinarians will treat for giardia based upon the cat's symptoms and without a definite diagnosis.

    Treatment

    • The de-wormer febendazole can help control giardia. Metronidazole may also be used, but it has many side effects. Furazolidone is sometimes prescribed, but it can cause vomiting and diarrhea.

    Humans

    • It is not known if the giardia protozoa that infects cats can infect people. There are many species of the protozoa, and it is unclear at this time if they are species-specific in the hosts they infect.