Madison, a three year old Labrador Retriever, was presented to Oswego Animal Hospital for a week long history of diarrhea, intermittent episodes of vomiting and lethargy. On physical examination, Madison was slightly dehydrated with no other abnormalities noted.
Due to Madison’s clinical signs of diarrhea, vomiting and lethargy, it was recommended that Madison have both blood work and a fecal test performed. Madison’s blood work came back within normal limits. However, Madison’s fecal test to look for intestinal parasites demonstrated a severe infection with Giardia.
Giardia is an intestinal protozoa that causes diarrhea, weight loss and vomiting in almost all species of animals. This organism lives in the small intestine and prevents adequate absorption of nutrients and water by disrupting the lining of the intestine. While diarrhea is the main clinical sign, some animals with long-term infections will only exhibit weight loss to due to poor nutrient absorption. Giardia exists in two forms: the trophozoite form which causes the intestinal damage and the cyst form which is the contagious form of the parasite. Cysts are shed in the feces and can live in the environment for up to one month.
Giardia is transmitted in a fecal-oral route meaning that the animals ingest the cysts from eating contaminated feces or accidently from environment contamination (drinking from a water source contaminated with Giardia). It has been estimated that up to 30% of cats and dogs have been exposed to this intestinal parasite in their lifetime.
Giardia is diagnosed by having a fecal test performed to look for the cyst form of the parasite indicating an active infection. However, Giardia can be difficult to diagnose because the cysts are intermittently shed during infection and can be missed on a fecal test if the animal is not shedding at that time. For this reason, a Giardia ELISA test was developed to help diagnose this intestinal parasite. An ELISA test works by looking for antibodies against an infectious agent indicating that the animal was exposed to the pathogen and that the animal’s immune system actively tried to fight off the pathogen.
Once an animal has diagnosed with Giardia, it is recommended that the animal receives medication to treat the infection. Madison received Panacur (Fenbendazole) in a granular form that the owner sprinkled over her food for five days in a row and then repeated the treatment course in two weeks. It is always recommended to have a fecal test performed one month after the last dosage of medication to ensure that the intestinal parasite infection has been treated.
To help prevent this intestinal parasite, it is recommended to prevent pets from eating animal feces or drinking out of bodies of water (lakes, rivers, ponds, etc) that can be contaminated with this parasite. If an animal is diagnosed with Giardia, it is recommended that their feces be picked up immediately to prevent further environmental contamination.
Madison did wonderfully taking her medication and her fecal test came back negative for Giardia one month after finishing her treatment. Madison made a full recovery and her owner is now more watchful of what Madison is eating on walks.