A small new study offers an intriguing clue about the baffling ailment known as chronic fatigue syndrome. Researchers in the UK say CFS, also known by its more scientific name of myalgic encephalomyelitis, appears to be triggered by an overactive immune system, reports the Guardian. Those who have CFS—including Seabiscuit and Unbroken author Laura Hillenbrand—suffer not just debilitating fatigue, but headaches, nausea, vertigo, and other symptoms that leave them unable to complete even the most basic tasks. The study suggests that sufferers may have an immune system that is genetically predisposed to go into hyper-drive when a virus or infection shows up, reports CNN. When it does, the cascade of debilitating—and easily misdiagnosed—symptoms begins. If the researchers are right, it could be a big first step on a poorly understood ailment.
"This is a light in the fog, a direction of travel," says King's College London researcher Carmine Pariante, per the BBC. "Although screening is a long way off, our results are the first step in identifying those at risk and catching the illness in its crucial early stages." The study involved 55 people with hepatitis C who were given the standard treatment of the drug interferon-alpha. This treatment typically produces symptoms consistent with CFS, and the researchers measured levels of a protein linked to inflammation in participants' blood before, during, and afterward. Eighteen people had a particularly strong immune reaction to the treatment—including fatigue—and they also had higher levels of the suspect protein before the treatment began. (Read more chronic fatigue syndrome stories.)