A new study reports chronic fatigue syndrome is not caused by the XMRV and pMLV viruses, as previously thought.
Health Day reported researchers from Columbia University, the National Institutes of Health, and other key institutions "examined 147 patients with chronic fatigue syndrome from sites across the country and compared them to 146 healthy patients."
The much anticipated results reported the journal mBio found "no link between the illness, also called myalgic encephalomyelitis, and mouse leukemia retroviruses, including one called XMRV," the New York Times reported.
Studies have previously found those with chronic fatigue syndrome had high levels of the virus, as scientists looked for the cause of this mysterious disease.
About 1 million Americans suffer from the condition, the Times wrote, which causes massive fatigue.
Women often suffer in higher proportion, which also affects memory and causes some joint and muscle pain, Health Day reported.