If you have cats, you’ve probably heard of the dangers of contracting Toxoplasmosis, a potentially fatal disease, from our cats’ feces (read the 10 Do’s & Don’ts of Cat Litter). Is it really something to worry about, or is it just a sensational headline? Watch the video below and read on for more information.
What is Toxoplasmosis?
- Toxoplasmosis is primarily a food borne illness, like Salmonella or Listeria, that is transmitted through eating undercooked meat or through ingesting food contaminated with the parasite, Toxoplasma gondii
- It is a global problem with up to half the world’s population, including 60 million Americans, currently carrying the Toxoplasma parasite, but it appears to be declining in some countries, including the US
- Most people develop no symptoms at all after infection because our immune system prevents the parasite from causing illness. But infected people may carry the parasite for life without ever knowing it (diagnosis is made through a blood test).
- Some infected people may experience mild Toxoplasmosis symptoms resembling a flu with swollen lymph glands, or muscle aches and pains that can last for several weeks to months, requiring no medical treatment
- People with weakened immune systems can have very serious side effects including fever, vomiting and seizures
- Pregnant women who are newly exposed to the parasite could infect their unborn child which could seriously harm their development, leading to vision loss and mental disability. According to the Centers for Disease Control and Prevention, “if you have been infected with Toxoplasma before becoming pregnant your unborn child is protected by your immunity. Some experts suggest waiting for 6 months after a recent infection to become pregnant.” Talk to your doctor if you are concerned about screening.
So where do cats come in?
Cats and Toxoplasmosis
- The cat family is a “definitive” host where the parasite can reproduce and pass through their feces. All other warm-blooded mammals, including rodents and birds, are “intermediary” hosts that can be infected through ingesting contaminated material.
- Cats don’t automatically carry the Toxoplasma parasite. Outdoor cats can ingest the parasite through eating any contaminated material like infected animals, or from contaminated soil where the parasite’s spores can survive for several months to year. Cats can also ingest the parasite through being fed raw meat. Kittens can get it from their mothers if they are infected. Like humans, healthy cats show no signs or symptoms of infection.
- Once infected, cats shed the parasite in their feces for up to 3 weeks in the form of microscopic oocysts. Of the 74-96 million house cats in the United States, approximately 1% of cats have intestinal infection at any time and will be shedding oocysts, so the prevalence of infected cats is low as compared to other parts of the world: 17% in Czechoslovakia, 20% in Brazil, 23% in Costa Rica, 40% in Turkey, 41% in Egypt.
- The parasite is only infectious in their feces through spores that develop after 1 to 5 days outside of the cat’s body, and can then survive in moist soil and water for several months to years.
- Poor hygiene can lead to accidentally ingesting the oocysts after cleaning the litter box, gardening in contaminated soil or ingesting anything contaminated by the parasite.
So the question remains:
Should you worry about getting Toxoplasmosis?
Acute infections in at-risk people can lead to hospitalization and death. In the United States, Toxoplasmosis causes an estimated 327 deaths, 400–4,000 cases of congenital (mother-to-child) transmission, 4,428 hospitalizations, and 4,800 cases of symptomatic eye disease each year, and an analysis showed a higher risk among “persons who were foreign-born, persons with a lower educational level, those who lived in crowded conditions, and those who worked in soil-related occupations.” Some studies have linked latent or dormant infections to long-term changes in behaviour and personality, mental disorders such as schizophrenia, and to the treatment of these disorders, while other studies have found no such link to schizophrenia (experts agree more research is needed in the long-term effects, if any, on latent Toxoplasmosis). So, yes, you should take great precautions to prevent acquiring Toxoplasmosis.
But to the question:
Should you worry about getting Toxoplasmosis from your cat?
You’re much more likely to get it from eating undercooked meat or contaminated water. Toxoplasmosis is very common in many countries where undercooked meat is eaten, like in France, where prenatal screening programs are in place to protect mothers and their babies. The CDC acknowledges that even if you are at high-risk for serious illness — immunocompromised individuals and pregnant women — the risk of getting Toxoplasmosis from your cat is so low there is no need to worry, and that you may keep your cat. But since Toxoplasmosis can be severe, you should still take standard precautions.
What can you do to prevent Toxoplasmosis?
- Only eat meat that has been well-cooked, and wash your fruits and vegetables thoroughly
- Freeze meat for several days at sub-zero temperatures before cooking
- Do not eat raw or undercooked oysters, mussels, or clams
- Wash utensils and surfaces well after coming into contact with raw meat or unwashed produce
- Teach children the importance of hand-washing and avoiding places that could be contaminated, and make sure that outdoor sandboxes are covered, especially in areas frequented by outdoor cats
- Keep cats indoors where they are much less likely to ingest the Toxoplasma parasite or pass it to other animals
- Only feed your cats canned or dry commercial-grade food or well-cooked meat
- NEVER flush used cat litter, even if it says it’s flushable. The parasite can survive filtration and harm aquatic wildlife and our drinking water.
- Avoid handling stray cats, or letting new cats into the home that might have been outdoor cats
- Since the parasite in the fecal matter is infectious only after 24 hours, clean the litter daily
- Wash your hands well with hot soap and water after cleaning the litter box or gardening
- Regularly replace all the cat litter and wash the litter box with hot water and a mild detergent (strong chemical and scents can deter cats and be toxic to them). This will depend on how many cats you have, the type of litter, and how many litter boxes you have. The Humane Society of the United States recommends every two to three weeks.
- If you are pregnant or immunocompromised, the CDC recommends getting someone else to clean the litter box, but that if you have to, wear disposable gloves when handling litter or while you’re gardening and wash your hands well
With education and simple precautions, there’s no reason to fear contracting Toxoplasmosis directly from your house cat. The CDC have targeted Toxoplasmosis as a priority based partly in the ability to prevent and treat the disease, and because little attention has been given to it thus far. You can apply the same safety procedures in preventing it as you would any other common foodborne illness like Salmonella or Listeria, and practice simple hygiene when you share your home with a cat.
The majority of recommendations in this article are from the Centers for Disease Control and Prevention. You can print out a pdf of their informative pamphlet, Toxoplasmosis: An Important Message for Cat Owners, here.
Remember, keep cats indoors, and spay/neuter
I hope this has shed some light on the concern over getting Toxoplasmosis from your cat. In short, you shouldn’t be, but do be aware of the risks of ingesting its parasite, Toxoplasma gondii, from undercooked meat and contaminated water.
However, pet guardians should be vigilant in stemming the spread of the parasite by keeping their cats indoors and spaying/neutering. Toxoplasmosis is a zoonotic disease, meaning that it is spread to humans from animals, and the cat family is the only host where the parasite can reproduce and spread from their feces, potentially infecting other wildlife and the environment, thereby affecting us. The ASPCA estimates that 74-96 million cats are owned in the United States, a number that has tripled in the last 40 years, with an additional 70 million living as strays. We are largely responsible for the growing population of cats, and through allowing our cats to be outdoors, we are potentially contributing to the spread of Toxoplasmosis to our food supply. So while the answer to the question, Should you worry about getting Toxoplasmosis directly from sharing your home with a cat, is no, we should definitely worry about indirect transmission from outdoor cats to the environment and back to humans.
As with any findings regarding disease and prevention, some scientists disagree with this information, so you should not take any of this material as the final word, and those interested may want to research the topic further. If you have any concerns or questions about Toxoplasmosis regarding you or your cat, please contact your health care provider and/or veterinarian.