Toxoplasmosis in cats is an infectious disease caused by the parasite Toxoplasma gondii. Toxoplasma is one of the most common parasites in cats and can infect nearly all warm-blooded animals. More than 60 million people in the U.S. are thought to be infected with Toxoplasma gondii, according to Cornell University's College of Veterinary Medicine. Although cats are a necessary part of the life cycle of Toxoplasma, the parasite rarely causes any sickness in cats.

Let's take a closer look at toxoplasmosis as well as possible signs that your cat may have this disease.

What is Toxoplasmosis in Cats?

Toxoplasma gondii is one of the most common internal parasites in cats. While Toxoplasma can infect any warm-blooded animal, including birds, cats are the definitive host of toxoplasma; therefore, this parasite can only replicate in cats.

Toxoplasma is shed in the feces of infected cats. Cats become infected with Toxoplasma by eating anything contaminated by feces from other infected cats. They can also become infected by eating rodents, birds or other small warm-blooded animals infected with Toxoplasma. Once a cat becomes infected with Toxoplasma, the parasite grows and replicates in the gastrointestinal tract. Cats that are newly infected with Toxoplasma are considered contagious for about two weeks after the initial infection.

Cats with compromised immune systems — such as cats infected with the leukemia virus, feline immunodeficiency virus (FIV), the virus that causes feline infectious peritonitis (FIP), Mycoplasma haemofelis, cats that are receiving chemotherapy or cats that have had a kidney transplant — are at an increased risk for developing severe or life-threatening complications associated with Toxoplasmosis.

Symptoms of Toxoplasmosis in Cats

After being exposed to Toxoplasma, most cats become immune and may never show any signs. A smaller proportion of cats may develop mild diarrhea and lose their appetite. Toxoplasma can also negatively impact a cat's liver, lungs and nervous system. Additional signs associated with Toxoplasma include:

  • Fever
  • Difficulty breathing
  • Vomiting
  • Weight loss
  • Abdominal distention due to fluid retention
  • Neurological signs, including seizures, incoordination, circling, head tilt
  • Red eyes, swollen eyes, blindness

If you think your cat might be infected with toxoplasma, schedule an appointment with your local veterinarian as soon as possible. To protect people and other warm-blooded animals in the household, use gloves when cleaning the litter box, prevent any other animals from accessing the litter box and always wash your hands after cleaning the box. Women who are pregnant should not clean the litter box.

Toxoplasmosis in Kittens

Kittens exposed to the parasite while still in the womb are the most vulnerable; they're more likely to show signs than adult cats. These kittens are often stillborn or die before weaning. If a kitten survives, they often won't eat, will develop a high fever that doesn't respond to antibiotic therapy, and suffer from severe respiratory and neurological complications as well as liver problems.

Transmission from Cats to Humans

Toxoplasmosis in cats is considered a zoonotic disease, which means that humans can contract toxoplasmosis from infected cats. However, because toxoplasmosis is such a common parasite, many have already been exposed and are immune to the disease. In most people, toxoplasmosis only causes mild flu-like signs; immunocompromised individuals may develop more severe signs, such as fever, heavy breathing or neurological problems like seizures.

The people who run the greatest risk of becoming infected with toxoplasmosis are women who are pregnant and those with weakened immune systems. If a pregnant woman becomes infected with Toxoplasmosis, the fetus can develop neurological abnormalities, or the infection can result in miscarriage or stillbirth. Visit the Center for Disease Control or consult your primary healthcare provider to learn more about Toxoplasma in humans.

Diagnosis and Treatment for Toxoplasmosis in Cats

Your veterinarian will utilize a combination of an oral history, physical exam and laboratory findings to diagnose Toxoplasmosis in your cat. Expect your vet to take blood and fecal samples, and they may require urine samples as well. If your cat is showing respiratory signs, your vet may order a chest X-ray. If neurological signs are noted, additional tests may be ordered. Toxoplasmosis in cats is definitively diagnosed by detecting antibody and antigen titers in the blood.

Unless they are very sick, cats who test positive for Toxoplasmosis are usually treated at home. The medication of choice for Toxoplasmosis is typically an antibiotic called Clindamycin, given twice daily for at least two weeks as prescribed by a veterinarian. Signs of the disease usually decrease fairly quickly after starting therapy. Very sick cats who cannot eat or drink adequately may be hospitalized for treatment.

Prevention of Toxoplasmosis in Cats

The easiest way to prevent Toxoplasmosis in your cat is to keep your cat indoors as well as avoiding feeding your cat raw meat, bones, viscera or unpasteurized milk. Preventing your cat from free roaming, hunting birds and rodents, or entering buildings where food-producing animals are housed, are additional ways you can protect your cat from this disease.

If you're pregnant, consider speaking with your veterinarian and having your cat tested for Toxoplasma. Healthy cats with positive antibody titers pose little danger to humans, but cats without an antibody titer are more at risk of becoming infected and posing a danger to humans. Your veterinarian can offer guidance. Additionally, talk with your doctor if you have questions about Toxoplasmosis and your pregnancy.

While Toxoplasmosis in cats is common, taking the necessary precautions can protect yourself and your cat from this disease.

Dr. Sarah Wooten Dr. Sarah Wooten

Dr. Sarah Wooten graduated from UC Davis School of Veterinary Medicine in 2002. A member of the American Society of Veterinary Journalists, Dr. Wooten divides her professional time between small animal practice in Greeley, Colorado, public speaking on associate issues, leadership, and client communication, and writing. She enjoys camping with her family, skiing, SCUBA, and participating in triathlons.

Related articles

Your Cat in Heat: What You Need to Know

Puppy, kitten and pet dieting, cat nutrition and dog nutrition information from Hill's Pet

What Is a Munchkin Cat?

Learn all about munchkin cats, including how to spot one, typical features & characteristics, personality, and any special care requirements.

Explaining Your Cat's Greeting

Learn about the different types of greetings cats can show you, such as head butting or slow blinking, and how to interpret each of her signals.

Why Does My Cat Attack My Feet?

Inquiring cat parents want to know: Why do cats attack feet? Why do cats like feet so much? Find out why your furry friend is nipping at your toes.

Are Bananas Safe for My Cat?

Are bananas safe for your cat? Learn helpful information on whether bananas are a good treat for your cat and why other options might be better.

Can Cats Get Asthma?

Could your cat's wheezing & breathing issues be an asthma attack, or is it just a hairball? Learn to recognize signs of asthma and what you should do.

Do Cats Fart?

While it may not be common, cats to indeed pass gas. Learn how your cat's food impacts their gassiness and whether you need to be concerned.

How to Talk to Cats (and Are They Really Listening?)

Learn tips for talking & communicating with your cat, including suggested gestures like blinking, as well as how to tell if they are actually listening.

Stage 1 Kidney Disease in Cats Often Goes Unnoticed

Learn more about stage 1 kidney disease in cats, such as the cause, symptoms, treatment and how the proper food can help manage her condition.

Choosing the Right Food for Your Senior Cat

Senior cats over age 7 have different nutritional needs than younger cats. Learn what to look for when choosing a food for older and aging felines.

Types of Cat Litter & How to Choose the Right One

Sift through our guide to learn about the many different types of cat litter and how to choose the best one for your feline friend.

The Effects of Catnip on Your Cat

Learn what catnip is, and whether or not it is safe to give to your cat and any side effects associated with catnip.

The Tales Your Cat's Tail Tells

Your cat's tail can tell you about what's going on inside her head. Tails are good indicators of mood. Take a little time to observe your cat's behavior and you will start to get a feel of the tales the tail tell

Gingivitis in Cats: Causes, Signs, Treatment & Prevention

Learn helpful info about gingivitis in cats, the most common oral disease among cats, including what it is, causes, symptoms, treatment & prevention tips.

Cat Arthritis: Signs, Causes and Treatment

Get the answers to your questions about cat arthritis here, from signs of arthritis in cats to treatment for feline arthritis.

5 Tips to Help Your Cat Exercise in Winter

Discover fun and creative cat exercise ideas to help your kitty stay fit and active through the winter months.

How to Clean Cat Ears: A Step-by-Step Guide

Does your cat need help keeping their ears clean? Check out this guide on how to clean cat ears, from when to consider it to what to use.

Feline Pancreatitis: What You Need to Know

Learn from a veterinarian: How to spot the serious signs of feline pancreatitis, emergency care, and what kind of diet to feed her while she's recovering.

Are Olives Safe for My Cat?

Learn the science behind why many cats are attracted to olives and love eating them, as well as any health concerns about stuffed olives and olive oil.

When Are Cats Full-Grown?

Learn key signs to tell if your kitten is reaching cat adulthood, including life stage specifics and special considerations for gender, breed & more