Toxoplasma gondii is a parasite commonly found in felines, but it can infect any warm-blooded animal including 30% of humans worldwide. A previous study revealed animals infected with it were more prone to show impulsive aggressive behaviors.
A group of scientists from the University of Chicago carried out a study to see if humans were affected in the same way. The work was submitted on October 29, 2014, and accepted in February this year.
Impulsive aggressive behavior is very common and sometimes, people snap for petty reasons. There are thousands of videos on YouTube featuring people losing their head over simple things like losing a match in a video game, the internet going down or any other little problem. Scientists proved that in a lot of these cases, people are infected with T. gondii.
Our beloved felines
The main host of the parasite is felines. Humans can be infected while handling cat litter, by drinking contaminated water or eating contaminated or undercooked meat. After the parasite is consumed, it travels through the body and establish itself in muscles and the brain. Scientists thought it was harmless, but recent studies have found that a more serious problem, intermittent explosive disorder (IED), might be linked to the infection.
Patients with IED have violent outbursts that sometimes lead to abrupt self-harming acts. Researchers studied 358 people. All the participants were evaluated in regards to aggressive, anxiety and other behaviors because scientists think the bacteria could also be implicated in personality disorders. The results are clear, a big portion of the participants diagnosed with IED also carried the bacteria.
In addition to this, the study also revealed increased levels of spontaneous aggression. Sex, race or socioeconomic status had nothing to do with it, but the participants with Toxoplasma gondii in their brains presented outbursts of rage. Sometimes, the subjects engaged in acts that they knew were going to harm them without any fatal risk, but in other cases, they put their lives at risk while having an episode.
“These findings are consistent with previous T. gondii seropositive status data, suggesting a relationship with self-directed aggression (ie, suicidal behavior) and a relationship involving schizophrenia or mania—disorders in which many individuals are often aggressive.59,60 Our results further add to the biological complexity of impulsive aggression, from both a categorical and a dimensional perspective.” the report reads.
In spite of this, the authors say that it is too early to take any drastic actions. Which means we don’t have to ban cats from our society. They claim that more studies are necessary because there is no evidence showing that treating the infection reduces aggressive behavior.
The full study was published online in the Journal of Clinical Psychiatry.
Source: Clinical Psychiatry