Cat Owners, Beware: A Parasite Might Be Controlling Your Behavior

We're sorry to break the news, but the same fur baby you've been cuddling with might literally be altering in your brain. You see, your cat could be the proud owner of a lovely little mind-altering parasite called Toxoplasma gondii, which can affect virtually any mammal on earth. Including you.

Why It's Important

Toxoplasma gondii is a single-celled protozoan that lives and reproduces in the guts of cats. Usually, it gets there by infecting the brains of prey animals like rats and mice and making them lose their fear of cat smell so they won't run when a cat tries to eat them. Though it gets into human brains more by accident—we won't be eaten by giant cats any time soon—it may still take a toll on our brains. The parasite has been linked to suicides, car crashes, mental disorders such as schizophrenia, and brain cancer. Scary stuff! A Czech evolutionary biologist, Jaroslav Flegr, controversially suggests that Toxoplasma gondii's effects go even further. He claims that infected men become more reckless, introverted, suspicious, and oblivious to other people's opinions to them. Infected women, on the other hand, become more outgoing, trusting, image-conscious, and rule-abiding, according to Flegr.

On the whole, however, side effects of the infection are subtle. Still, it can be especially harmful to pregnant women and people with weakened immune systems.

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Why You Should Care

As we said, you can easily get this parasite from your cat. But how? Since it lives in Fluffy's gut, it eventually makes it into the litter box. You clean the litter box, forget to wash your hands, go to eat something, and bam—toxoplasmosis.

Cleaning the litter box isn't the only way you can become infected with Toxoplasma gondii, however. Anywhere cat feces might wind up, including contaminated drinking water and unwashed vegetables, can be a carrier of the parasite. Undercooked meat can also be a source. But this is just one parasite, which begs the question: How many other parasites are controlling our minds?

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Written by Curiosity Staff December 15, 2016

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