Giardia in Dogs and Cats

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Giardia in Dogs and Cats

Giardia is a microscopic, single-cell parasite that can live in the intestine of animals or people. This parasite causes the infection known as Giardiasis. Read on to learn about signs, treatment, and prevention in dogs and cats.

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What is Giardia?

Giardia duodenalis, found worldwide, is a tiny one-celled protozoan parasite. Mature parasites live in the small and large intestines of dogs and sometimes cats, blocking the absorption of nutrients from food. It is there that the parasite multiplies and eventually becomes cysts. Cysts are shed in the feces of an infected pet. Once cysts are accidentally ingested the cycle begins again.

How is Giardia transmitted?

The most common cause of Giardia is ingestion of water or soil that has been contaminated with infected feces. Sources may be ponds, lakes, and streams but also include environments such as dog kennels, animal shelters, and pet stores. Dogs and cats pass the parasitic cyst in their stools into the environment. The stool is immediately infectious.

Can I get Giardia from my pet?

Transmission of Giardia from pets and wildlife to humans is uncommon. Human to human transmission as well as ingestion of contaminated water or soil is the most likely cause of infection in humans. Thorough hand washing can help to decrease the risk of infection.

How will I know if my pet has Giardia?

Signs that your dog or cat may have Giardia include:

  • Decreased appetite
  • Mucus in stools
  • Diarrhea with or without blood
  • Vomiting
  • Dehydration
  • Tiredness
  • Gas
  • Weight loss
  • Many dogs have no signs of illness

How is Giardia diagnosed in dogs and cats?

Definitive diagnosis is determined by Giardia-specific fecal examination. Often, patients are presumptively diagnosed and treated based on clinical signs and medical history.

How is Giardia treated in pets?

Once a diagnosis of Giardia is made, your vet will recommend the most appropriate treatment for your pet. Commonly, this involves prescription medication.

Removing your pet’s stool and disinfecting the environment will help to prevent the potential spread of Giardia to other pets and people. Bathing pets can help to remove cysts from the fur and skin, decreasing the likelihood of reinfection.

The prognosis for pets suffering from Giardia is good, although geriatric or those patients with weakened immune systems may be at increased risk of serious complications. Hospitalization may be recommended for these individuals. Always follow the recommendations of your veterinarian.

Read more:

Roundworms in Dogs and Cats

Hookworms in Dog and Cats

Coccidia in Dogs and Cats

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Published: 7/9/2021
Last updated: 7/30/2021

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