Flu, AIDS, meningitis, Ebola, polio, herpes, measles, rabies—the list of diseases caused by viruses is a litany of woe ranging from the merely annoying to the deadly. Every year almost two million people are killed by the human immunodeficiency virus (HIV), and around half that many people succumb to viral hepatitis infections. The economic toll of viral illnesses is nearly as staggering as the human one; flu costs the United States an estimated $25 billion a year, and HIV costs $36 billion. To make matters worse, new viruses continue to appear (see “Virus Hunter” below), often after hiding in animal populations for centuries before moving into humans—as did HIV, avian flu, and severe acute respiratory syndrome (SARS). But while public health officials and physicians focus on the threat of emerging viruses, little-noticed research is implicating these primitive microbes in diseases long thought to have nothing to do with them: mental illnesses.
The notion that “insanity is infectious,” as virologist Ian Lipkin of Columbia University’s Mailman School of Public Health bluntly puts it, goes back to antiquity. As late as the 1800s, the mentally ill were locked away because, among other reasons, they were thought to be contagious. The notion wasn’t completely misguided. Until the discovery of penicillin ushered in the age of antibiotics, a major cause of mental illness was syphilis. But biomedicine is subject to fads and fashion no less than skirts are, and over the last 40 years disease detectives seeking the cause of mental conditions such as schizophrenia, bipolar disorder, autism, and obsessive-compulsive disorder have turned from microbes to genes as the cause. And now, a parade of discoveries suggests that viruses may be the culprit rather than your family tree. The new research indicates that viral infection can affect the developing brain and contribute to mental illnesses even before birth….
by Sharon Begley
The Saturday Evening Post