The Infection Connection

Abstract

M ichael Harrington, a neurologist at the National Institute of Mental Health (NIMH) in Bethesda, Md., knows that his slides of protein patterns taken from the spinal fluid of healthy and schizophrenic persons are not setting the scientific world on fire. Many people have criticized our work and called it a fishing expedition, he says. Yet the fish he and his colleagues recently netted actually no more than tiny splotches on specially prepared, computer-analyzed strips of gel may pan out nicely, leading to the identification of viruses that could contribute to some cases of schizophrenia. Theories about a possible role for viral infections in schizophrenia have circulated in the psychiatric community for more than a century. But research attempting to demonstrate such a link provided only indirect evidence and is fraught with pitfalls, says psychiatrist Charles A. Kaufmann of St. Elizabeths Hospital in Washington, D.C. The infectious disease theory has traditionally stirred up controversy, a hallmark of much research on mental illness. The term schizophrenia encompasses a number of disorders that are caused, according to various schools of thought, by genes, stress, early family interactions, a biochemical imbalance, infections, nutrition or some combination of these factors. Symptoms are severe and include social withdrawal, incoherent speech, blunted emotions, delusions and hallucinations. At least 2 million people in the United States are estimated to have some form of schizophrenia. In the past 10 years a number of brain diseases, such as multiple sclerosis (which also affects the spinal cord) and Alzheimer's disease, have been increasingly examined for evidence of viral infection. Viruses are of interest to schizophrenia researchers for a number of reasons, explains psychiatrist E. Fuller Torrey of St. Elizabeths Hospital. They often influence the nervous system, they may not flare up into active infections for 20 years or more, they wax and wane in their intensity and they can alter brain cell function without causing visible, surface changes. One way to tell whether viruses are at work is to look for changes in protein production in spinal fluid, which closely reflects brain proteins, says Harrington. Only recently, however, have researchers developed techniques that detect trace amounts of protein. More than 300 proteins now can be separated by electrical charge and mass in gel preparations, il-