Infection eyed as culprit in chronic disease

There are skeptics, but this line of research is gaining attention.

By Susan J. Landers, AMNews staff. July 19, 2004.

Washington -- Imagine prescribing antibiotics for patients with atherosclerosis, or administering vaccines to prevent schizophrenia. Many researchers are thinking outside the box and are pursuing the infectious agents they believe might play a large role in causing chronic diseases.

"It is becoming increasingly acceptable and recognized that infections are probably an underappreciated cause of chronic disease," said Siobhan O'Connor, MD, MPH, assistant to the director of the National Center for Infectious Diseases at the Centers for Disease Control and Prevention.

The list of chronic diseases known to be caused by infectious agents is growing. AIDS, cervical cancer, liver cancer and peptic ulcers all result from these bugs, and researchers are exploring links to heart disease, additional cancers and psychiatric disorders. About 70% of all deaths in the United States are caused by chronic diseases, making them a prime target for research attention.

There was a time when the very idea of an infectious agent causing a chronic disease brought heaps of scorn upon the scientists who proposed it. That's what happened in the 1980s when it was suggested that ulcers were caused by Helicobacter pylori rather than stress and spicy food. Since then, H. pylori has been linked to duodenal ulcers, gastric cancer and certain types of lymphomas.

The ulcer story caused a shift in thinking that went well beyond that one disease, said E. Fuller Torrey, MD, associate director of laboratory research at the Stanley Medical Research Institute. He has been examining the role of infectious agents in schizophrenia and bipolar disorder "for more years than I care to remember." As for the current status of his research: "I wouldn't say we were respectable, but we are no longer not respectable, either."