Giardia is a common parasite that can infect the intestinal tract of many species, including dogs, cats, livestock, wildlife, and people. Our Pets & Friends Animal Hospital team negates the myths, revealing the truth behind this common illness, so you can better protect your pet from Giardia infection.

True or false? Giardia is an intestinal parasite that is similar to worms

False: Although Giardia is an intestinal parasite, it is not a worm such as roundworms, whipworms, or hookworms. Giardia is a single-celled, protozoal parasite. Giardia is much tinier than other intestinal parasites, but it can still wreak havoc on your furry pal’s digestive tract.

True or false? Giardia eggs require incubation time before becoming infectious

False: Giardia does not form an egg as do other intestinal parasites. However, in its cyst stage, Giardia causes infection. These cysts are immediately infectious as soon as your dog expels them when they defecate.

True or false? Giardia is an easy infection for dogs to contract

True: Because Giardia is immediately infectious as soon as an affected dog sheds cysts in their feces, the condition is incredibly easy for other dogs to contract. Giardia can be transmitted via:

  • Direct contact with an infected dog — If your dog plays with a Giardia-infected dog, they may accidentally ingest cysts by grooming, licking, or sniffing the affected dog.
  • Exposure to contaminated ground or water sources — Giardia is a hardy parasite that can thrive in the environment for months. When an infected dog defecates, Giardia cysts can contaminate dirt, grass, and water. If your dog drinks from a contaminated puddle, chews a stick, or eats contaminated feces, they can contract the disease.
  • Poor hygiene practices — If your dog is housed in an improperly cleaned kennel at a boarding or grooming facility, or if they eat or drink from a dirty bowl, they can contract Giardia.

True or false? Your dog may not show giardiasis signs

True: Giardiasis is a complicated illness, as infection does not always cause obvious signs. In fact, many infected dogs show no signs, while others develop chronic diarrhea that waxes and wanes. Infected dogs typically produce particularly malodorous, pale, and greasy stool. Other giardiasis signs include:

  • Excessive gas
  • Abdominal cramping and discomfort
  • Lethargy
  • Poor hair coat
  • Decreased appetite
  • Weight loss
  • Vomiting

True or false? Giardia is easily diagnosed

False: An infected dog intermittently sheds Giardia in their feces, so the cysts may not be present in every sample our Pets & Friends Animal Hospital team examines. To confirm a dog’s Giardia diagnosis, we may need to examine two or three consecutive fecal samples. However, standard fecal exams may yield negative results, despite the hallmark giardiasis signs that include malodorous, pale, greasy stool.

We can perform a reliable Giardia test within 10 minutes in our hospital. This test checks for Giardia antigens’ presence. The Giardia parasite produces a specific antigen that indicates a dog has the condition. This diagnostic test is not dependent on cyst-shedding action.

True or false? Deworming medication will eliminate Giardia

False: Unlike other intestinal parasites, Giardia often can’t be fully eliminated through a simple deworming treatment. An extended treatment plan may be necessary, and includes multiple deworming, antibiotic, and probiotic rounds, and a prescription diet. 

While giardiasis can be challenging to treat, not all dogs require treatment. If Giardia is an incidental finding on a routine fecal exam, but the dog is not showing signs, treatment may not be warranted.

True or false? Your dog can easily become reinfected with Giardia

True: Because Giardia cysts are immediately infectious as soon as your dog eliminates them through their feces, reinfection can easily occur. To prevent your dog’s Giardia reinfection, follow these tips:

  • Clean your yard — Your yard can become a Giardia hotspot if you fail to pick up your dog’s feces immediately. Sunlight is the only natural element that tackles Giardia, so confine your dog to one elimination area during treatment, then avoid that area once their treatment is complete.
  • Bathe your dog — Bathing your dog during their giardiasis treatment course helps prevent reinfection. Focus on their hind end and paws to remove cysts.
  • Disinfect your dog’s belongings — By regularly disinfecting your dog’s bedding, toys, and bowls, you help kill Giardia cysts and prevent reinfection.

True or false? My dog can also pass Giardia to me

False: Giardia has numerous strains that often affect only a few chosen species. The Giardia strain your dog contracts likely won’t be one that can infect you, and vice versa. However, good hygiene is still important to prevent potential parasite transmission.

Prevention is key to keeping your furry pal safe from Giardia. However, if your dog develops diarrhea, this protozoal parasite may be the cause. Schedule an appointment with our Pets & Friends Animal Hospital team, so we can diagnose the cause and treat your dog’s diarrhea.