A parasite found in undercooked food and cat feces may be responsible for a surprising number of schizophrenia cases.
Gary Smith, PhD, of the School of Veterinary Medicine at the University of Pennsylvania, using epidemiological modeling, estimates that the parasite, Toxoplasma gondii, is responsible for more than one-fifth of schizophrenia cases.
Prior research has linked T. gondii to schizophrenia as the infection is known to enter the brain. In addition, animal studies have shown infection with T. gondii leads to changes in behavior and personality.
While just over 20% of the U.S. population is infected with the parasite, most people are able to fend it off with no ill effects.
Using a population attributable fraction, or PAF, a metric epidemiologists use to determine how significant a risk factor might be, Smith found that 21.4% of schizophrenia cases would not have happened if T. gondii was not present. The results were presented in the journal Preventive Veterinary Medicine.
“Instead of ridiculing the idea of a connection between T. gondii and schizophrenia because it seems so extraordinary, we can sit down and consider the evidence,” he said in a statement. “Perhaps then we might be persuaded to look for more ways to reduce the number of people infected with Toxoplasma.”
Some research has indicated certain antipsychotic drugs may be effective in stopping the parasite from reproducing.
A parasite responsible for toxoplasmosis — Toxoplasma gondii — may be involved in the cause of around a fifth of schizophrenia cases in the US. This is according to a new study published in the journal Preventive Veterinary Medicine. University of Pennsylvania researcher Greg Smith calculated that around a fifth of schizophrenia cases may be attributable to T. gondii.
More recently, studies have linked T. gondii infection to schizophrenia, and some have found that antipsychotic medication may even stop the parasite from replicating. But such research has been met with much criticism.