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Giardia in Cats

Posted Jan 27th, 2022

Giardia in Cats

Giardia is a group of protozoan parasites that are typically found in the stool of your cat and can infect people, as well as other dogs and cats, and can cause symptoms such as diarrhea and upset stomach. Our Sacramento vets give insight on how to tell if your cat may be infected with Giardia, and what to do if they are.

Cat Giardia Parasite

Giardia Duodenalis is a protozoan parasite that is capable of infecting many different types of mammals, including cats, dogs, and people. The many different strains of Giardia are categorized by letters from A through H with cats typically being infected by the F genotype and humans being most susceptible to genotypes A and B. That said, while rare, it is possible for cats to harbor strains A and B, potentially causing infection in their owners.

Giardia is most commonly seen in cats and kittens that are suffering from underlying health conditions. Unfortunately, Giardia can be challenging to deal with since treatment isn't always effective and it is common for reinfection to occur.

How is giardia spread?

GIardia is always transmitted through the fecal-oral route. When Giardia parasites are present in a cat's stool it is possible for other animals (or people) to come into contact with the infected stool. When this happens the parasite can travel into the new host's body through ingestion or inhalation. This can be caused by either direct contact with the infected stool, through drinking water that has been contaminated, or through the contaminated soil. 

Can you get giardia from your cat?

The most common way for humans to become infected with Giardia is by drinking contaminated water. 

While cats have the potential to carry the A strain of Giardia which people are susceptible to, the spread of the parasite from cats to humans is very uncommon. 

Even so, precautions should always be taken in order to protect yourself from a variety of parasites and viruses, such as wearing gloves while changing cat litter, washing your hands well after handling your cat, and disinfecting items that come in contact with your cat is advised. (including the litter box, water bowls. bedding, toys etc.). If you have a compromised immune system it is imperative that you take extra care when you might have to come into contact with cat feces, like when changing the litter box.

Disinfect surfaces that your cat comes in contact with using a solution of chlorine bleach at a dilution of 1:16 or 1:32.

What are the signs of giardia in cats?

Giardia parasites damage the cat's intestinal wall and commonly cause the sudden onset of foul-smelling diarrhea. It is common that cats who have become infected with Giardia do not show any symptoms at all, however, if your cat has giardiasis you may notice:

  • Cat's stool is soft to watery and may have a greenish tinge or contain blood.
  • Excess mucus in the feces may be apparent.
  • Vomiting may occur in some cases.
  • Lethargy in some cases.
  • Symptoms of giardiasis listed above may persist for several weeks resulting in weight loss.

It is not uncommon for diarrhea related to giardiasis may be intermittent. Typically fevers are not common with giardia infections in cats.

What is the treatment for cat giardia?

A cat infected with the Giardia parasite may be especially difficult to treat as they typically require multiple and possibly combinations of treatments in order to eliminate the parasite completely. Some Giardia strains can be incredibly resistant to the medication used for treatment. As a result, multiple drugs or more than one attempt at therapy may be needed.

The most commonly prescribed treatments for giardia in cats are Fenbendazole and metronidazole.

  • Fenbendazole may reduce clinical signs and shedding of the parasite. This treatment is administered to the infected cat orally for 3 to 5 days and is safe for pregnant cats.
  • Metronidazole is a medication that appears to be more effective at treating giardia in cats than dogs. Treatment is given for 5 to 7 days and is not safe for pregnant cats.

In certain cases, the two medications can be given in combination to fight giardiasis.

Your vet may also prescribe a highly digestible diet until your cat's stool hardens. Prolonged bouts of vomiting and diarrhea can quickly result in dehydration so it's important to ensure that your cat remains well hydrated.

How long will my cat have giardia?

It generally takes between 3 to 5 days for the parasites to be cleared from the stool once antibiotic treatment begins, and 5 to 7 days for symptoms to resolve. During this time it is important to protect yourself and any other animals and treat the necessary surfaces with the appropriate cleaning products. 

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Are you concerned that your cat might be infected with the Giardia parasite? Contact us today to book an appointment for your cat. Our vets are experienced in treating many parasitic conditions in pets.

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Elkhorn-Walerga Animal Hospital is accepting new patients! Our experienced vets are passionate about the health of Sacramento companion animals. Get in touch today to book your pet's first appointment.

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