Stomach Bug Linked to Chronic Fatigue Syndrome

Researchers seeking the cause of chronic fatigue syndrome have linked a group of intestinal viruses to the disease, according to a new study. About 80% of patients with the syndrome showed signs of enterovirus gut infections, compared to only about 20% of otherwise healthy volunteers. "It opens up a new direction in the research for this elusive disease," said the study's author.

Some are skeptical that there's a cause-and-effect relationship. "This is an illness with a lot of different origins, and to assume that its cause is due to an infection is a leap," said a scientist with the Centers for Disease Control. The syndrome is characterized by  exhaustion not relieved by sleep.  (More virus stories.)