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Giardia in Cats

Giardia is a parasite that can be seen in cats, dogs, and people. It can cause symptoms such as diarrhea and an upset stomach. In this article, our Somerset vets explain Giardia in cats including how it spreads, its symptoms, and treatment options.

Giardia Parasite in Cats

Giardia duodenalis is a protozoan parasite that can infect cats, dogs, and humans, among other mammals. Giardia is divided into several strains, each of which is labeled with a letter from A to H. Cats are more likely to be infected with assemblage F, whereas people are more likely to be infected with assemblages A and B. Cats can, however, harbor strains A and B, which can cause infection in their owners.

The condition is most often seen in kittens and cats that are suffering from poor health due to other underlying conditions. 

Giardia can be challenging for pet parents to deal with since treatment isn't always effective and reinfection will often occur.

The Transmissibility of Giardia

The fecal-oral route is used to transmit all giardia strains. This means that giardia parasites are present in the stool of an infected cat, and when other animals (or people) come into contact with the infected stool, the parasite enters the new host's body through ingestion or inhalation. This can occur through direct contact with contaminated stool, inhalation of soil that has come into contact with contaminated stool, or ingestion of contaminated water.

Felin Giardia Transmitting to Humans

Giardia infections are common in people however drinking contaminated water is the most common way for people to catch giardia. 

While it is possible for cats to harbor the A strain of giardia (dogs can harbor the B strain) that people are susceptible to, the spread of giardiasis from cats to people is not very common.

Wearing gloves while changing cat litter, washing your hands thoroughly after handling your cat, and disinfecting items that come into contact with your cat are all recommended precautions. (This includes the litter box, water bowls, bedding, and toys, among other things). If their cat has been diagnosed with giardia, people with compromised immune systems should be extra cautious about disinfecting.

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

Signs & Symptoms of Giardia in Cats

Giardia parasites cause damage to the intestinal wall of cats, resulting in sudden bouts of foul-smelling diarrhea. Although not all cats infected with Giardia will show symptoms of infection, if your cat has giardiasis, you may notice the following:

  • Vomiting
  • Lethargy
  • Weight loss
  • Soft/watery, greenish, and/or bloody stool
  • Excess mucus in the feces

Treatment for Giardia in Cats

Giardia in cats can be difficult to eradicate, and it may take several treatments or a combination of treatments to eradicate the parasite. Because some giardia strains are resistant to medication, eradicating the disease can be difficult. As a result, multiple drugs or multiple therapy attempts may be required.

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

  • 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 some instances, 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.

The best way to treat your cat is to have them treated with parasite prevention measures so they don't develop Giardia in the first place.

How Long Giardia in Cats Lasts

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.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. Please make an appointment with your vet to accurately diagnose your pet's condition.

Is your cat showing signs of Giardia? Contact our Somerset vets today to book an appointment for your feline friend.

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Spinnaker Veterinary Clinic welcomes cats, dogs, and their people to our clinic! Our experienced vets are passionate about the health of Somerset companion animals. Get in touch today to book your pet's appointment.

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