Toxoplasmosis infection correlates to higher suicide rate in women.
As a cat lady myself, I have long been fascinated with the strange puzzle that is the toxoplasma parasite. Alarmingly, a new study shows a strong correlation between toxoplasmosis in women and suicide attempts. Odder still, women with toxoplasmosis are more likely to commit suicide by violent means (stabbing, gunshot, jumping) than non-infected women.
Scientifically known as Toxoplasma gondii, this parasite is communicated to humans through the cat's waste, typically by cleaning the litter box. (Not only is it a gross job, it's also potentially parasitic!) In its normal life cycle, the toxoplasma parasite infects rats and mice. It makes them unafraid of the smell of cat urine, and more likely to take crazy risks. By subtly controlling the behavior of infected rodents, toxoplasma positions them to be eaten by cats, which are crucial for its next life stage.
But when cats came to live with us, so did the toxoplasma parasite. Clinically, toxoplasmosis (the disease caused by infection with the parasite) is relatively harmless in non-pregnant adults with a healthy immune system. (Because it can cause spontaneous miscarriages in pregnant women, women who are or wish to be pregnant are advised to stay away from the litter box.) You might come down with vaguely flu-like symptoms for a little while. No big deal.
However, several broad statistical studies have shown that toxoplasmosis seems to have an effect on human behavior over the long term, too. Between 10 percent and 20 percent of the population in the United States is infected with toxoplasma, and the infection correlates to a lot of interesting and unusual personality changes. People infected with toxoplasma become more fond of cats, for one thing.
Toxoplasma infection has also been linked to schizophrenia: schizophrenics are four times as likely to be carrying the toxoplasma parasite than non-schizophrenics.
Toxoplasma's effects are also strangely gender specific. Women are more likely to be rated as "warm" or "friendly," while men are more likely to become "suspicious and antisocial." Toxoplasmosis is linked to a higher incidence of risk taking behavior in men. And in women, it is linked to an increased incidence of suicide.
Women with antibodies to T. gondii are 1.5 times more likely to attempt suicide. And stranger still, the worse the infection, the more likely it is that the woman will attempt suicide.
Whether or not you are a cat lady, if you are experiencing suicidal thoughts, please reach out for help. In the United States you can call the National Suicide Prevention Lifeline 24/7 at 1-800-273-8255.