Toxoplasma gondii is a single-celled parasite that has the power to transform a timid mouse into a fearless cat-seeking rodent. Cats that eat such mice may subsequently infect people with the parasite.
What transpires to infected persons, though? Do they turn into Toxoplasma gondii zombies that behave how the parasite sees fit?
The answer is complicated; research indicates that persons who test positive for toxoplasmosis are more prone to take particular sorts of risks than those who do not, but it is still unclear how this occurs.
Although Toxoplasma gondii may survive in various species, it usually begins its life cycle within a mouse or rat. According to a 2019 study published on the preprint database bioRxiv, this is probably because cats prey on rodents, giving the parasite a route to the cat gut, the only place where it is known to be able to reproduce because cat guts are rich in linoleic acid, a component required for Toxoplasma gondii sex.
Toxoplasma gondii uses a rather unsettling method, brain manipulation, to facilitate this change from vermin to feline host. Rodents’ behavior is changed by the parasite, which makes them less risk-averse. Additionally, it is believed to make mice drawn to the smell of cat excrement. In other words, the parasite alters the way that mice and rats think, increasing their propensity to go out in front of cats where they would be captured, killed, and devoured. Toxoplasma gondii may infect humans; in fact, toxoplasmosis, the infection this parasite causes, is considered to affect at least one-third of the world’s population. While some people become sick while cleaning out the litter box of their beloved cat, many of us simply consume undercooked foods or unwashed veggies. What does this entail for the one in three of us who become the parasite’s host, then?
