Immunology researchers have established there’s no evidence of an infectious cause behind the chronic fatigue syndrome (CFS), prompting warnings an understanding of what triggers the debilitating illness could be a decade away.
In 2009 a paper in the journal Science made a possible connection between chronic fatigue syndrome and the retrovirus XMRV. The paper was later retracted.
This week a study published in mBio, the online journal of the American Society for Microbiology, revealed no evidence of infection with retroviruses XMRV and pMLV in a study of 147 patients with chronic fatigue syndrome.
“We went ahead and set up a study to test this thing once and for all and determine whether we could find footprints of these viruses in people with chronic fatigue syndrome or in healthy controls,” said study co-author Ian Lipkin, from Columbia University’s Centre for Infection and Immunity.
“These results refute any correlation between these agents and disease,” Dr Lipkin said.
Syndromes intrinsically have “woolly boundaries” said Andrew Lloyd, infectious diseases physician and immunology researcher at the UNSW. “Not everybody within the syndrome label will necessarily have the same illness, there may be more than one illness within the label and some people will be mislabelled.”
But Dr Lloyd said the Columbia University study was “the final nail in the coffin” in the link between XMRV and the family of gammaretroviruses and chronic fatigue syndrome.
“Does that mean that viruses don’t have a role? Absolutely not – it’s clear that viral infections act as a trigger.
“The next question is, is persistence of those virus the driver of ongoing illness, and the answer to that is no.”
However Dr Lloyd said it’s still possibile there are viruses not yet discovered that cause chronic fatigue syndrome, and it’s also in theory possible that a virus might act as a co-factor.
“This whole viral XMRV storyline is actually a distraction,” he added, with researchers now moving their focus to the brain.
Dr Lloyd said that the theory of academic research of CFS had already moved on from infectious viruses.
“Finally three decades later the Americans have arrived back where started,” said Ian Hickie, professor of psychiatry at University of Sydney.
“If you had to choose a place in the body where the problem lies we’re already 99.9% confident the problem is in the brain and we already have some ideas about how the brain might be disturbed to generate this illness,“ Dr Lloyd said.
He added that it would be a “minimum of a decade before we really get to the heart of the matter”, adding that those affected by CFS needed to be patient while the scientific process ran its course.
“The tools available to investigate the central nervous system now in this decade are much greater than they were so we need to capitalise on that, reduce the nonsense, and get on with using those tools to try and find solutions that really help people,” Professor Hickie said.