People with the condition are much more likely than others to harbor a little-known pathogen
The long, fruitless search for the cause of chronic fatigue syndrome has taken a curious turn. Scientists report online October 8 in Science that an obscure retrovirus shows up in two-thirds of people diagnosed with the condition. The researchers also show the retrovirus can infect human immune cells.
These findings don’t establish that the pathogen, called gammaretrovirus XMRV, causes chronic fatigue, cautions study coauthor Robert Silverman, a molecular biologist at the Lerner Research Institute of the Cleveland Clinic. “Nevertheless, it’s exciting because it is a viable candidate for a cause.”
Roughly 1 to 4 million people in the United States have chronic fatigue syndrome, according to the Centers for Disease Control and Prevention. The condition shows up as mental and physical exhaustion, memory lapses, muscle pain, insomnia, digestive distress and other health problems. Doctors often diagnose chronic fatigue only after ruling