Coccidia in kittens and cats inhabit the intestinal tract. There are several species of these tiny parasites that are found in cats and other mammals, and some species are contagious to humans. The good news is that healthy adult cats rarely get sick with coccidia, and most cats can beat coccidia infections on their own without treatment. Read on to learn more about coccidia in cats as well as signs that your cat might have these parasites.

What Is Coccidia in Cats?

Coccidia are parasites that live in the gastrointestinal tract of cats and other mammals. There are several species of coccidia parasites, and cats can harbor a few different types. Common types include Isospora felis and Isospora rivolta, intestinal parasites that only infect cats, and Cryptosporidium parvum and Toxoplasma gondii, two coccidia species which are both known to be zoonotic, or contagious to humans.

No matter the species of coccidia, they're all spread the same way: accidental ingestion of sporulated oocysts, the infectious life stage of coccidia parasites. Oocysts lurk in feces from cats infected with the parasite, or food or water contaminated with feces. Toxoplasma can also be spread by consuming raw meat infected with parasitic cysts; therefore, cats that hunt or eat raw meat are at higher risk for developing coccidia.

Signs of Coccidia in Cats

Signs of a coccidia infection vary based on the species of coccidia as well as the age and health of the cat. Coccidia in kittens usually causes more clinical signs than coccidia in healthy adult cats because kittens typically have a weaker immune system relative to adult cats. On the other hand, there may be no signs in adult cats — the cat may look and act completely healthy and be able to overcome the infection without treatment. Cats with other underlying health issues are at higher risk for developing coccidia.

Signs of coccidia in kittens include watery or mucusy diarrhea that is sometimes streaked with blood. A severe infection of coccidia in kittens can cause weakness. Signs of a possible infection with Toxoplasma may include no signs at all, or the cat may display signs such as:

• Excessive tiredness or sleeping
• Weight loss
• Fever
• Excessive eye discharge or squinting
• Difficulty breathing
• Diarrhea
• Vomiting
• Loss of balance
• Seizures
• Weakness

Another factor to consider is that pregnant cats infected with Toxoplasma may deliver stillborn kittens. However, male cats seem to be at a higher risk for Toxoplasma than female cats.

Diagnosing Coccidia in Cats

If you suspect your cat is suffering from a coccidia infection, make an appointment to have your cat seen by your local veterinarian. When you take your cat to see the vet, try to bring a fresh sample of feces with you. Typically, coccidia can be diagnosed by a combination of history from you, a physical exam of your cat and a microscopic fecal examination.

Because many cats can be infected without the appearance of clinical signs, it's important to get your cat's feces tested at least yearly to make sure your cat isn't unknowingly harboring and spreading the parasite. However, the good news for toxoplasmosis is that cats only shed this parasite for around 7 days after the first time they're exposed. So although repeat exposure may cause your cat to become sick, it would be unlikely that they would be at risk of exposing other pets or people in your house to the parasite.

If your cat is visibly sick or the vet suspects a Toxoplasma infection or other disease, then the vet may order additional tests to check how your cat's internal organs are functioning and rule out other diseases. They may also do blood tests that look for antibodies against the toxoplasma parasite to help determine if they've ever been exposed or are dealing with an active infection.