"The researchers, led by Robert H. Yolken, M.D., of the Stanley Laboratory of Developmental Neurovirology at the Johns Hopkins University School of Medicine and E. Fuller Torrey of the Stanley Medical Research Institute, compared an unpublished survey on mental illness from 1982 and two later studies, which found an association between long-term childhood exposure to cats and the development of serious mental illnesses, including schizophrenia and bipolar disorder."Granted, the link rests in exposure to cat feces, which can contain a parasite called Toxoplasma gondii. The parasite is relatively harmless to the bulk of the population, but can be devastating to those with compromised immune systems. Men and women who are immunocompromised can develop toxoplasmosis, which can, on top of raising the risk for mental illness, cause photophobia, blindness, miscarriages in pregnant women, fetal birth defects, and even death.
According to estimates by the Centers for Disease Control, as many as 60 million people in the United States may be infected with Toxoplasma gondii.
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