Toxoplasma

By Rebecca Hernandez

Toxoplasma amoebae in the process of producing daughter cells

I hate to say it, but there’s a good chance you’ve got this little bugger in your brain - about half of the world’s population is infected with this mind-bending amoeba.

This single-celled parasite’s primary host is cats, so it’s possible to infect yourself if you don’t wash your hands properly after changing Fluffy’s kitty litter. Fortunately most people’s immune systems are strong enough to keep Toxoplasma at bay.

However, recent research suggests that if it affects enough brain cells, it can actually cause neurotic behaviour, including severe anxiety, depression, and even schizophrenic-like symptoms.

Some scientists even hold Toxoplasma responsible for more global implications; they suggest that a high rate of Toxoplasma infection could shift an entire population’s behaviour and these shifts might explain fundamental differences in human cultures. For example, recent research found that countries with high Toxoplasma prevalence tended to have higher aggregate neuroticism scores than other countries. This could lead to different countries having different work ethics.

A brain altering parasite? Possibly, but don’t give the cat away yet.

Interesting fact: It’s not just human behaviour that Toxoplasma affects. The amoeba makes infected rats less afraid of cats, which increases the chances of the parasite reach its preferred feline host.

Danger of Death: Only 10-20% of people show any acute symptoms of infection, but for anyone with decreased immune function, Toxoplasma can be deadly.

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