Cat feces parasite Toxoplasma gondii can increase schizophrenia risk

Cats, particularly the outdoor or stray ones, might have a parasite called T. gondii or Toxoplasma gondii in their feces. T. gondii is capable of infecting all kinds of warm-blooded animal including us, the humans. According to the number put forward by the CDC, at this moment the United States is home to around 60 million individuals who carry this parasite.

The most worrying feature of the parasite is that individuals infected by it usually don’t experience any symptom; however, some with the excessively weak immune system might develop a condition called toxoplasmosis. Toxoplasmosis is often linked to flu-like discomforts, fetal development disorders, blindness, and miscarriage.

Scientists have recently found that other than causing toxoplasmosis, T. gondii might also be responsible for occurrence of different mental illnesses.


In a study published in the widely read mental health journal Schizophrenia Research, scientists have claimed that individuals, who had cats during childhood, are at high risk of developing mental illnesses such as bipolar disorder and schizophrenia later on.

During this new study, the researchers compared the findings of a couple of previous studies that analyzed links between schizophrenia and cat ownership. The findings of those studies supplement a recent study carried out by the Academic Medical Center in Amsterdam and suggest that there might be connections between cat exposure during childhood and mental disorders.

The Dutch study, on the other hand, is suggesting that an individual infected with the parasite T. gondii remains at two times higher risk of developing schizophrenia compared to people who don’t have it.

The past decades have seen a number of studies talking about connections between the infection caused by T. gondii and subtle behavioral changes, which include increase in the level of dopamine, introversion in men and extroversion in women, lack of inhibition even if the situation is scary or risky and so on.

Another major fact presented by those past studies is that T. gondii infection also increase’s one’s chances of getting into a motor accident by 100%. In spite of all these revelations made by the study, one should not freak out and stop having cats. This is because the study hasn’t succeeded in proving that T. gondii can cause mental disorders. The study has only hypothesized that the parasite might do so.