You get toxoplasmosis from cats by accidentally swallowing a microscopic parasite called Toxoplasma gondii, which is shed in an infected cat’s feces. The key word is “accidentally.” This isn’t something you catch from petting your cat, being scratched, or sharing a couch. It happens through contact with contaminated feces, usually during litter box cleaning, gardening in contaminated soil, or eating unwashed produce from a garden where cats have been.
Why Cats Are the Only Source
Cats, both domestic and wild, are the only animals in which Toxoplasma gondii completes its full reproductive cycle. When a cat eats infected prey (a mouse, bird, or raw meat), the parasite multiplies inside the cat’s intestinal lining and produces tiny egg-like structures called oocysts. The cat then sheds millions of these oocysts in its feces over a short window, typically between days four and eleven after the initial infection. This shedding period usually happens only once in a cat’s lifetime.
At any given time, roughly 1% of domestic cats are actively shedding oocysts. Surveys across different U.S. states have found active shedding rates ranging from 0% to 6.6%, with an average around 0.7%. So while cats are the sole definitive host for this parasite, the chance that your specific cat is shedding right now is quite low.
How Oocysts Actually Reach You
Fresh cat feces aren’t immediately dangerous. Oocysts need one to five days after being shed to become infectious, a process called sporulation. This delay is important because it means daily litter box cleaning significantly reduces your risk. If you scoop the litter every 24 hours, you’re removing the feces before the parasite inside them can infect anyone.
The most common ways people accidentally ingest the parasite from cats include:
- Cleaning the litter box and then touching your mouth, food, or face without washing your hands thoroughly
- Gardening or digging in soil where cats have defecated, then transferring the parasite to your mouth via unwashed hands
- Eating unwashed fruits or vegetables from a garden where outdoor cats roam
- Children playing in sandboxes that cats have used as a toilet
Once oocysts sporulate in soil, they can survive for months to over a year in warm, moist conditions. This is why garden soil and outdoor sandboxes pose a real, if underappreciated, risk long after a cat has moved on.
Which Cats Pose the Highest Risk
Not all cats are equally likely to carry the parasite. Cats get infected by eating raw or undercooked meat, or by hunting and consuming prey animals like rodents and birds. That means outdoor cats that hunt are the primary concern. Indoor cats that eat only commercially prepared, cooked food are unlikely to ever encounter the parasite in the first place.
Feeding your cat a raw meat diet also increases the risk. Cooking inactivates any Toxoplasma cysts present in meat, so standard commercial cat food is considered safe. If your cat stays indoors, doesn’t hunt, and eats cooked food, the odds of it ever shedding oocysts are very low.
Cat Contact vs. Cat Feces
A common misconception is that simply living with a cat puts you at high risk. It doesn’t. You cannot get toxoplasmosis from a cat licking you, sleeping on your bed, or rubbing against your legs. The parasite is transmitted exclusively through the fecal-oral route, meaning something contaminated with cat feces has to reach your mouth. Casual contact with your cat is not a transmission pathway.
It’s also worth noting that undercooked meat is actually a more common source of human toxoplasmosis than cat litter. The CDC lists contaminated undercooked meat and shellfish alongside cat feces as major routes of infection. Many people who test positive for Toxoplasma antibodies were never directly exposed to cat feces at all.
Practical Steps to Prevent Infection
The single most effective habit is scooping the litter box every day. Because oocysts take one to five days to become infectious after being shed, daily cleaning removes them before they pose a threat. If you’re pregnant or have a weakened immune system, have someone else handle litter duty entirely. If that’s not possible, wear disposable gloves and wash your hands thoroughly with soap and warm water immediately afterward.
Gardening deserves the same caution. Wear gloves whenever you work in soil or handle sand, especially in areas where cats may have defecated. Wash your hands with soap and warm water when you come inside, and scrub any homegrown produce before eating it.
To reduce your cat’s risk of ever picking up the parasite, keep it indoors and avoid feeding raw meat or unpasteurized milk. An indoor cat on a standard commercial diet has minimal opportunity to become infected, which means it has minimal opportunity to infect you.
Why Pregnancy Gets Special Attention
Toxoplasmosis is a mild or even invisible infection for most healthy adults. Many people never realize they’ve had it. But a first-time infection during pregnancy can cross the placenta and cause serious harm to the developing baby, including vision problems, brain damage, or miscarriage. This is why the warnings around cat litter and pregnancy are so emphatic.
The risk is specifically tied to a new infection during pregnancy, not a past one. If you were infected before becoming pregnant, your immune system has already built defenses that protect the fetus. The concern is for women who encounter the parasite for the first time while pregnant. For this group, avoiding litter box contact, wearing gloves while gardening, and thorough hand washing are simple precautions that dramatically cut the risk.