CFS and HHV-6

 http://hhv-6foundation.org/associated-conditions/hhv-6-and-chronic-fatigue-syndrome

"HHV-6 has long been suspected as one trigger for CFS. HHV-6 reactivation in transplant patients can cause symptoms similar to CFS, including fatigue, cognitive dysfunction and autonomic dysfunction (Zerr 2012). Direct evidence of persistent central nervous system (CNS) infection is difficult to obtain, however, with current standard laboratory tests, as HHV-6 can persist in the CNS long after it has disappeared from the blood stream."
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 http://www.sciencedaily.com/releases/2013/07/130726092427.htm
"Many experts believe that chronic fatigue syndrome (CFS) has several root causes including some viruses. Now, lead scientists Shara Pantry, Maria Medveczky and Peter Medveczky of the University of South Florida's Morsani College of Medicine, along with the help of several collaborating scientists and clinicians, have published an article in the Journal of Medical Virology suggesting that a common virus, Human Herpesvirus 6 (HHV-6), is the possible cause of some CFS cases."
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 http://www.drpodell.org/chronic-fatigue-syndrome-hhv6.shtml
"Dr. Jose Montoya, a chronic fatigue syndrome physician at Stanford Medical School, treated 25 chronic fatigue syndrome (CFS) patients with Valcyte, an oral medicine that blocks HHV-6, Epstein Barr virus and other Herpes family viruses."
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http://www.sott.net/article/264201-Chronic-fatigue-syndrome-a-herpes-virus-infection-of-the-vagus-nerve

"Michael VanElzakker, a researcher affiliated with the Tufts University PTSD neuroimaging laboratory as well as the Massachusetts General Hospital Psychiatric Neuroscience division, has published a novel hypothesis on the possible etiology of Chronic Fatigue Syndrome (CFS). In the paper, published in Medical Hypotheses, VanElzakker suggests that CFS may be the result of a pathological infection of the vagus nerve. Although VanElzakker proposes that any neutoropic virus or bacteria could trigger CFS, HHV-6 is at the top of his list."