Scientists have studied the parasite that cats infect humans. Promise to release a vaccine

For 70 years, science has known an extremely widespread and subtly acting parasite called Toxoplasma gondii , by which domestic cats infect the brains of their owners, causing them to change personality . Among the changes are increased riskiness (confirmed), slower reactions (confirmed), love for cats (not confirmed, but possible), schizophrenia and paranoia (in rare cases). Moreover, individual researchers believe that "in populations where this parasite is very common, massive personality changes can lead to changes in their culture."

Fortunately, recent scientific research allows us to hope that soon humanity will finally get rid of “cat addiction”.

Toxoplasma is one of the most common parasites in developed countries. It is distributed through cat droppings and unroasted meat. According to available estimates, 30-80% of the population are carriers, the figure varies greatly from country to country. Caused personality changes are usually too insignificant and invisible, the same schizophrenia is not diagnosed in all patients, so for most of us it is safe. However, toxoplasmosis can cause very serious consequences in people with a vulnerable immune system and pregnant women, increasing the risk of miscarriage or birth defects in a newborn.

A group of scientists from Australia studied in detail the life cycle of Toxoplasma gondii, including the mechanism of cell capture and food accumulation. New evidence may even help create a cure for toxoplasmosis.

A living creature from a cat captures brain cells such as neurons. To ensure his own growth and survival, he is able to hide his existence for decades, accumulating food reserves and completely hiding from the human immune system until his death. “The parasite does this by introducing special proteins into the host cell, modifying the original intracellular signaling pathways, which allows it to grow and multiply,” said Chris Tonkin of the Australian Institute Walter and Eliza Hall, co-author of the study.



Thanks to a more thorough study of the life cycle of the parasite, it is now possible to check whether mental illness is caused by the influence of the parasite. It is known that some people develop certain mental illnesses, including schizophrenia and bipolar disorder.

“We found that, like animals that are preparing for hibernation, Toxoplasma gondii accumulates a large amount of starch when they enter sleep mode,” says Tonkin. “If you determine and disable the mechanism that activates the accumulation of starch, as it turned out, you can kill an inactive parasite by preventing the spread of chronic infection.”

Scientists promise to create a vaccine that completely prevents the cat’s influence on humans, that is, it eliminates the risk of infection with Toxoplasma gondii.

The scientific work is published in the magazines Cell Host & Microbe and eLife .