Cats and Toxoplasmosis

By Katie McHenry

We often see news publications print articles about toxoplasmosis, causing not only widespread fear but also sweeping misinformation: “‘Cat Lady’ Parasite Linked to Permanent Brain Damage” (ABC News), “How Your Cat Is Making You Crazy” (The Atlantic), “Cat Poop Parasite Is Dangerously Widespread” (Live Science), to name just a few.

These inaccurate and overstated headlines can have devastating consequences, leaving untold numbers of cats homeless when their guardians begin planning families. We would like to separate fact from fiction surrounding this issue and invite you to explore this issue further.

What Is Toxoplasmosis, and What Are Its Symptoms?

According to the U.S. Centers for Disease Control (CDC), toxoplasmosis is an infection carried by the protozoan (single-celled) parasite called Toxoplasma gondii. Most healthy individuals who contract the infection won’t manifest symptoms, but for those with weakened immune systems (such as pregnant women, the elderly and HIV patients), symptoms range from swollen lymph glands and muscle aches to blurred vision and, in severe cases, brain or eye damage.

How Common Is this Type of Infection, and How Do People Contract It?

Per the CDC, “In the United States it is estimated that 22.5% of the population 12 years and older have been infected with Toxoplasma. In various places throughout the world, it has been shown that up to 95% of some populations have been infected with Toxoplasma.” However, so long as the individual is healthy, a person with toxoplasmosis more than likely won’t even know he or she has the infection.

While litter boxes are one potential avenue for a toxoplasmosis infection, it is not a common source of infection, especially if the litter box is scooped once or twice a day. In fact, according to the CDC, “The Toxoplasma parasite does not become infectious until 1 to 5 days after it is shed in a cat’s feces,” and therefore, according to the Humane Society of the United States, “exposure to the disease is unlikely as long as you clean the cat’s litter box daily.” A more likely culprit is actually our food supply: every year, consumers contract toxoplasmosis from undercooked meat, unwashed fruits and vegetables or even unpasteurized goat’s milk. Cornell University’s College of Veterinary Medicine asserts, “In the United States, people are much more likely to become infected through eating raw meat and unwashed fruits and vegetables than from handling cat feces.”

The CDC also states that, in order to help prevent a foodborne toxoplasmosis infection, consumers should be diligent in thoroughly washing and/or peeling produce; cooking meat to the appropriate temperature (and even freezing meat at subzero temperatures for several days before preparation); thoroughly washing their hands, utensils and kitchen surfaces that may have come into contact with raw meat; and avoiding unpasteurized goat’s milk.

If a Person Is Pregnant or Has a Weakened Immune System, Should He or She Surrender the Family Cat?

Such drastic measures aren’t necessary, but a person who’s pregnant or has a weakened immune system should take extra precautions, such as:

• Get your cat tested: Your cat can be tested for exposure to toxoplasmosis by your vet; the test can be done through a special fecal or blood test. However, exposure to toxoplasmosis doesn’t necessarily mean your cat has an active infection. Only during an active infection, and more than 24 hours after a cat uses the litter box, can accidental ingestion of your cat’s feces infect you with toxoplasmosis. As the CDC notes, “Toxoplasma cannot be absorbed through intact skin.”
• Scoop your cat’s litter box at least once a day: As noted previously, it takes between one and five days for Toxoplasma to become infectious. (A cat’s litter box should be scooped at least once a day, but preferably twice a day, regardless of whether toxoplasmosis is a concern.)
• Ask someone else scoop the litter box: However, if a pregnant woman scoops the litter box herself, she needs to wash her hands thoroughly with soap and hot water (just like anyone else for basic hygiene). If she wants to take extra precaution, she can also wear and dispose of gloves then wash her hands afterwards.
• Keep your cat indoors: There are many reasons to keep your cat indoors, but preventing toxoplasmosis is an additional motive. Cats can become infected with the parasite from eating another animal, such as a squirrel, that is infected with Toxoplasma; the parasite stays in the cat’s system between one and three weeks, during which time the cat sheds the parasite via his or her feces.
• Feed your cat canned or dry food: Cats on a raw food diet are at risk of contracting the parasite via the consumption of raw meat.

In other words, if you are a cat guardian, you stand a greater chance of getting toxoplasmosis from how you cook your dinner than from your cat! Remember, if your cat is indoors-only, is not already infected and does not consume raw meat, your cat’s chances of picking up the Toxoplasma parasite remains virtually non-existent. And it’s easy to also take additional steps to reduce your risk of exposure from your cat, such as scooping the litter box at least once a day (before the feces becomes infectious) and thoroughly washing your hands afterwards.

Even if you don’t have a cat, you can also reduce your risk of contracting toxoplasmosis by always remembering to thoroughly cook your meat and wash your produce, abstain from unpasteurized goat’s milk and wear gloves if you garden, to protect your hands from potentially contaminated soil. For further information, please visit the online resources provided by the U.S. Centers for Disease Control (CDC) or the Cornell University College of Veterinary Medicine.