Imagine going to work or school every day, working out at the gym, spending time with family and friends—basically, living your life in a full and vigorous way. Then one day, you wake up, feeling sick. A bad cold maybe, or perhaps the flu. A few days pass, and you think it should be over—but it’s not, you still feel achy and exhausted. Now imagine that you never get better— plagued by unrelenting fatigue not relieved by sleep. Any exertion just makes you worse. You are forced to leave your job or school and are unable to participate in any of your favorite activities; some days you can’t even get out of bed. The worst part is that your doctors don’t know what is wrong and nothing seems to help.
Unfortunately, this is not fiction, but reality for at least a million Americans—who suffer from a condition that carries the unwieldy name of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), a perplexing disease that biomedical research desperately needs to unravel . Very little is currently known about what causes ME/CFS or its biological basis . Among the many possibilities that need to be explored are problems in cellular metabolism and changes in the immune system.
A number of studies suggest that abnormalities in cellular metabolism, a complex biological process that the body uses to create energy , may underlie ME/CFS. A recent study of metabolite pathways in blood samples from people with ME/CFS reported a signature suggestive of a hypometabolic condition, similar to a phenomenon biologists have studied in other organisms and refer to by the term “dauer” (a hibernation-like state) . A number of other studies have suggested that changes in the immune system may play a causal role in ME/CFS , either due to a post-infectious autoimmune process or due to a unknown chronic infection.
To date, most studies in ME/CFS have looked at relatively small numbers of people with ME/CFS and employed different methods—and rarely has a finding been replicated. Given the heterogeneity of the illness and complexity of the assays, rigorous confirmatory studies in larger groups of people with ME/CFS are necessary to provide the evidence base for effective therapy development. ME/CFS, as much as any other disorder, is in need of a concerted effort by the scientific community to understand its biological basis.
The NIH is committed to stimulating additional research to reveal the causes of this debilitating disease. ME/CFS is such a complex condition, affecting so many body systems, that we do not know where the answers will come from. Informed by results from a 2014 ME/CFS workshop , NIH initiated a call to action to all of its relevant Institutes and Centers in October 2015. The resultant NIH research effort, led by Trans-NIH ME/CFS Working Group, leverages an impressive scope of expertise across the NIH to attack this research gap.
The Trans-NIH ME/CFS Working Group recently solicited research applications to seed a nationally coordinated approach to understand the cause(s) and mechanisms of ME/CFS. In January, NIH issued two Funding Opportunity Announcements (FOAs). These FOAs seek to establish a research consortium for ME/CFS research, including a coordinating center to facilitate collaborative science among the sites and enable widespread data sharing. The consortium will provide a foundation upon which rigorous ME/CFS research can build to make new discoveries, validate research findings, and attract new investigators from various disciplines to study ME/CFS.
The research consortium is just a first step toward growing an innovative and vigorous research community to focus on this disease. The NIH is always open for other scientists to submit research grants on ME/CFS, and most NIH funding goes to these regular grant proposals, which are reviewed on a three times per year cycle. In addition, a variety of other research initiatives were recently launched. The NIH awarded seven Administrative Supplements to expand ME/CFS research in current grants. These projects use state-of-the-art technology to pinpoint genes that may be involved in the disease and to reveal how specific immune cells play a role in ME/CFS. Some of these projects will zero in on potential biomarkers, which are desperately needed to help with diagnosis and for tracking disease progression. Descriptions of these awards can be found at: https://www.nih.gov/mecfs/funding.
The NIH is also initiating ME/CFS research at the NIH Clinical Center in Bethesda, MD. Led by Dr. Avindra Nath, an expert in neurovirology and infections of the nervous system, dozens of investigators from seven of NIH’s Institutes and Centers will carry out an extremely detailed and comprehensive evaluation of several dozen people with ME/CFS, focusing on those whose symptoms can be clearly traced to an infectious-like illness and who have been sick for less than five years. These volunteers will undergo a comprehensive battery of tests, including blood draws and brain scans, to help researchers learn more about the clinical and biological features of this disease.
One of our goals is to improve communication about these research efforts to individuals with ME/CFS and advocates who have been affected by this devastating disease. We host regular telebriefings, which enable NIH staff to update the community on our activities and provide ME/CFS stakeholders with an opportunity to ask questions and offer their perspectives. You can learn about NIH’s ME/CFS-related efforts and briefings by visiting the ME/CFS website at www.nih.gov/mecfs. If you would like to receive periodic updates from NIH by email, please visit the ME/CFS website and click on “Join our listserv.”
We recognize and empathize with the suffering experienced by people with ME/CFS and their frustration that so little is known and so little research has been done to find answers. We aim to change that. The NIH is committed to unraveling the underlying biologic cause(s) of ME/CFS as swiftly as possible, and promoting research that will inform the development of effective strategies for treatment and prevention of this devastating condition.
Note: Walter Koroshetz, M.D. is Director of the National Institute of Neurological Disorders and Stroke (NINDS), NIH; Francis Collins, M.D., Ph.D., is the Director of the National Institutes of Health (NIH).
 Beyond myalgic encephalomyelitis/chronic fatigue syndrome: Redefining an illness. Institute of Medicine. Washington, DC: The National Academies Press. 2015.
 Workshop Resources, NIH Pathways to Prevention Workshop: Advancing the Research on Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Office of Disease Prevention, NIH. 2014 Dec 9-10.
 Metabolic profiling indicates impaired pyruvate dehydrogenase function in myalgic encephalopathy/ chronic fatigue syndrome. Fluge Ø, Mella O, Bruland O, Risa K, Dyrstad SE, Alme K, Rekeland IG, Sapkota D, Røsland GV, Fosså A, Ktoridou-Valen I, Lunde S, Sørland K, Lien K, Herder I, Thürmer H, Gotaas ME, Baranowska KA, Bohnen LM, Schäfer C, McCann A, Sommerfelt K, Helgeland L, Ueland PM, Dahl O, Tronstad KJ. JCI Insight. 2016 Dec 22;1(21):e89376.
 Metabolic profiling of a myalgic encephalomyelitis/chronic fatigue syndrome discovery cohort reveals disturbances in fatty acid and lipid metabolism. Germain A, Ruppert D, Levine SM, Hanson MR. Mol Biosystems. 2017 Jan 31;13(2):371-379.
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 Impaired calcium mobilization in natural killer cells from chronic fatigue syndrome/myalgic encephalomyelitis patients is associated with transient receptor potential melastatin 3 ion channels. Nguyen T, Johnston S, Clarke L, Smith P, Staines D, Marshall-Gradisnik S. Clinical & Experimental Immunology. 2017 Feb;187(2):284-293.
 Illness progression in chronic fatigue syndrome: a shifting immune baseline. Russell L, Broderick G, Taylor R, Fernandes H, Harvey J, Barnes Z, Smylie A, Collado F, Balbin EG, Katz BZ, Klimas NG, Fletcher MA. BMC Immunol. 2016 Mar 10;17:3.
 National Institutes of Health Pathways to Prevention Workshop: Advancing the Research on Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Green CR, Cowan P, Elk R, O’Neil KM, Rasmussen AL. Ann Intern Med. 2015 Jun 16;162(12):860-865.
Chronic Fatigue Syndrome (Medline Plus, National Library of Medicine/NIH)
Beyond Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Redefining an Illness (National Academies of Sciences, Engineering, and Medicine, Washington, D.C)