That sweet little cat that purrs and sits on your lap could be carrying a disease that can facilitate miscarriages, fetal development disorders, weeks of flu-like illness, blindness, and even death. It has also been associated with mental health problems, including schizophrenia and bipolar disorder.
The parasite toxoplasma gondii (T. gondii) is one of the most commonly carried parasites. It can attach itself to, and infect, any warm-blooded species, and is often carried by cats. It is possible that you may be carrying it yourself. The Centers for Disease Control and Prevention (CDC) estimates that more than 60 million people in the U.S. may have it.
If you do have it, you may not notice it or have any symptoms, although people with weakened immune systems are much more likely to exhibit symptoms and be affected. If you are infected with T. gondii you can contract an illness called toxoplasmosis, which could lead to flu-like symptoms or miscarriages if you are pregnant. Two more studies have been published that associate it with mental health disorders.
Mental health link
Several universities have conducted research for decades in order to prove a causal link between the parasite and mental health problems. E. Fuller Torrey, of the Stanley Medical Research Institute, and Dr. Robert H. Yolken, from the Stanley Laboratory of Developmental Neurovirology at the Johns Hopkins University School of Medicine, have been studying the link between the T. gondii infection and schizophrenia. Their most recent work was published in Schizophrenia Research.
Researcher Wendy Simmons, who also worked with Torrey and Yolken, has compared their research with studies that were conducted previously. These studies explored a link with owning a cat as a child and then developing schizophrenia later in life.
Simmons explored an unpublished survey on mental health from 1982, 10 years before any data on cat ownership and mental illness had been published. By comparing the studies, they concluded that exposure to a cat in childhood may have a connection, or be a risk factor, for developing mental disorders.
Another recent study, which was conducted by the Department of Psychiatry at the Academic Medical Centre in Amsterdam, investigated the findings of 50 published studies. They confirmed that the T. gondii infection is associated with mental disorders. Results showed that an individual infected with T. gondii was almost twice as likely to develop schizophrenia.
"In schizophrenia, the evidence of an association with T. gondii is overwhelming," the authors said. "These findings may give further clues about how T. gondii infection can possibly alter the risk of specific psychiatric disorders." This research was published in the journal Acta Psychiatrica Scandinavica.
The cat population is huge, and according to the Humane Society there are 75 to 80 million pet cats and another 30 to 40 million stray or feral cats roaming the United States. It would make perfect sense to say that outdoor cats have an increased likelihood of infection.
What to do
You can protect your children by making sure your cat stays indoors. If you have a sand box, keep it covered when you aren’t using it. The CDC recommends that pet owners change their cat's litter box daily, since T. gondii does not become infectious until one to five days after it is shed in feces. Also take precaution in feeding cats raw food or food that hasn’t been cooked all the way through.
Toxoplasmosis is something an unborn baby can be affected by, so it is recommended that pregnant women avoid cleaning litter boxes. If this cannot be avoided, be sure to wear disposable gloves and wash your hands.