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Parasite Found in Kitty Litter may Cause Mental Illness

Susan Patterson
February 22nd, 2013
Updated 02/22/2013 at 3:10 am
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animalcat 265x165 Parasite Found in Kitty Litter may Cause Mental IllnessSomething very bad may be lurking in your kitty litter box. According to new research out of Sweden, a very common cat litter parasite, known as Toxoplasma gondii, may contribute to mental illness. Between 30-50% of the world population is infected with Toxoplasmosis, caused by exposure to the parasite in question. According to the Centers for Disease Control and Prevention (CDC), over 60 million people worldwide may be infected. Swedish experts estimate that 20% of their population has been infected.

Parasite Exposure

The most common point of contact between humans and this nasty parasite is in poorly cooked meat. The CDC reports that toxoplasmosis is the leading cause of death from foodborne illness. People can also become infected by touching cat feces when cleaning the litter.


If you have a strong immune system, it is unlikely that you will ever know that you have been exposed to the parasite. However, infection can cause mild like flu symptoms before heading into a symptomless dormant stage. The real concern is with people who have a stressed immune system or those that are pregnant. The parasite can enter the brain of fetuses and people whose bodies are too weak to put up a defense.

Risky Behavior and Toxoplasmosis

Although toxoplasmosis appears to go dormant in healthy subjects, researchers are now concerned that perhaps there is more going on behind this symptomless facade.

Some studies have found that people who have toxoplasmosis have a higher rate of depression, anxiety and schizophrenia. This information coupled with the fact that infected laboratory rats are not afraid of cats and may even be attracted to them. They become easy prey and scientists feel that this is how the parasite assures its survival. The cats consume the infected rats and more parasites turn up in their feces that will infect more rats.

Once the parasite is in the brain it appears to hijack the chemical messengers responsible for passing signals to different parts of the brain to secure their propagation. Isolated research done on infected cells indicates that the parasite causes immune cells to secrete a chemical messenger known as GABA. People with mental illnesses such as bipolar disease, anxiety, depression and schizophrenia  all show disturbances with GABA systems.

Other research, published in the Archives of General Psychiatry, came to similar conclusions as far as mental status being compromised. Looking at 45,000 women in Denmark, the researchers found that those infected with T. gondii were 1.5 times more likely to attempt suicide than those unaffected.

“The fact that a parasite can get into an organism, target its brain, stay there without killing the host and alter the circuitry of the brain— we’ve seen this in insects and fungi, but it’s the first time we’ve seen it in a mammalian host,” said Stanford University’s Patrick House.

Although humans have lived with parasites since the beginning of time, these studies warrant further investigation into the role of this parasite and potential mental illnesses in our society.

Tip: Always wash your hands after changing the kitty litter, stay clear of littler if you are pregnant, and cook all your meat well.

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  • stv

    Remember that many lone older folks use animals, dogs or cuts for therapy and company. It is a good idea those more susceptible to health risks to be aware of what is going on. Prevention is better than cure. Pathogens of any form and shape that "hibernate" ( lie dormant) in your body are only waiting for the right environment or opportunity to do what they are designed to do; repeat their cycle of life which is more often than not at the expense of the host ,

  • @Joshiedooozie

    A compromised/weak immune system leads to many issues/dangers; Toxoplasmosis is one of them. But strange how it is more likely to happen to those infected with HIV/AIDS, those with t-cells below 200. Are we all infected with the parasite? Does it simply lie dormant until the immune system becomes weak?

  • Hal Hanson

    The article said: "Tip: Always wash your hands after changing the kitty litter, stay clear of littler if you are pregnant, and cook all your meat well."

    Well, duh. What is the point? I am sure dog feces has things to steer clear of also but how many people are out there scooping with their hands protected only be plastic bags? Sounds like alarmist fodder to have something to fill up the blog-o-sphere….

  • Violet

    Cats are safe, awesome & toxoplasmosis is extremely rare! See Dr Becker from Mercola's article on it: