Gammaretrovirus Thought to be Important Cause of Chronic Fatigue
November 12, 2009
Earlier this month, a study published in the journal Science answered a question that medical scientists had been asking since 2006, when they learned of a novel virus found in prostate tumors called xenotropic murine leukemia virus-related virus, or XMRV: Was it a human infection?
The new study provided overwhelming evidence that XMRV is a human gammaretrovirus — the third human retrovirus (after H.I.V. and human lymphotropic viruses, which cause leukemia and lymphoma). Infection is permanent and, yes, it can spread from person to person (though it is not yet known how the virus is transmitted).
That would have been news enough, but there was more. XMRV had been discovered in people suffering from chronic fatigue syndrome, a malady whose very existence has been a subject of debate for 25 years. For sufferers of this disease, the news has offered enormous hope. Being seriously ill for years, even decades, is nightmarish enough, but patients are also the targets of ridicule and hostility that stem from the perception that it is all in their heads. In the study, 67 percent of the 101 patients with the disease were found to have XMRV in their cells.
Many people don’t realize how severe this illness can be. It is marked by memory and cognition problems, and physical collapse after any mental or physical exertion. The various co-infections that occur only make matters worse. Many patients are bedridden. And recovery is rare. A significant number of patients have been ill for more than two decades.
It is estimated that more than a million Americans are seriously ill with the disease. (Not everyone infected with XMRV will necessarily get chronic fatigue syndrome — in the same way that not all of the 1.1 million Americans infected with HIV will get AIDS.)