The Formative Years

The first definitive description of an illness resembling poliomyelitis was by Gilliam after the 1930s Los Angeles outbreak. Careful clinical observation in all the epidemics repeatedly found reproducible signs and a distinctive pattern of CNS and sensory nerve involvement, muscle weakness with pain or tenderness, and emotional lability with a chronic, relapsing course.

In the 1950s, the public eye was caught by several outbreaks of a mysterious illness that incapacitated communities, often in hospitals. In the Iceland epidemic it was noted patients who contracted the illness developed immunity to poliomyelitis, suggesting confirmation of an association.

Autopsy findings on experimentally infected monkeys during the Adelaide epidemic led to the conclusion that the disorder was caused by inflammation of the brain and spinal cord. Accordingly, names such as atypical polio and Akiyuri disease were replaced in 1956 in the UK by the term Benign myalgic encephalomyelitis. However, autopsies on humans have revealed only evidence of infection, notably in the brain, heart, and skeletal muscle.

WHO Classification and Disgrace

ME has been included in the classification of the World Health Organization (WHO) as a disease of the central nervous system since 1969.

In the ICD-10, ME is the only disorder listed in the tabular classification under G93.3, Post-viral fatigue syndrome (PVFS).

Despite the increasing prevalence of non-epidemic cases, the disorder was soon dismissed by some as mass hysteria due to the 1970 McEvedy and Beard speculative research, in which no patients were examined. Interest dropped, to be rekindled only after a similar outbreak at Incline Village, Lake Tahoe, Nevada in the mid-1980s.

CDC Intervention

In 1987, researchers from the Centers for Disease Control & Prevention (CDC) assumed that the cases they observed during the mid 1980s were not ME, and therefore attached a different name to the phenomenon: Chronic Fatigue Syndrome (CFS). The criteria are broader than those for ME and the assumption that the two disorders are identical requires testing.

The Centers for Disease Control & Prevention published a first working case definition for CFS in 1988,[240]. In 1993 the term Chronic fatigue syndrome (CFS) was added to the alphabetic list of the WHO ICD classification.

Villified but Vindicated

Research increased, more so after the criteria were relaxed in 1994, but was criticised for over-inclusiveness. With all objective signs now expunged, the obvious possibility of misdiagnosis bedevilled clinical and research work. Lacking a diagnostic laboratory test of any kind, CFS has frequently been misdiagnosed, for example, in patients presenting CFS symptoms with similar biological conditions or infections (such as Lyme disease or Epstein-Barr, the latter of which is often the cause of glandular fever, or infectious mononucleosis), or psychological conditions (ranging from depression to hypochondria).

A lack of information and awareness has led to many patients being stigmatised, sometimes as hypochondriacs or lazy, yet at other times as over-active and perfectionistic. Because immune-related symptoms are common in ME patients, their immune system was suspected to be dysfunctional, or responding inappropriately to specific viruses; this lead to the proposal of the alternative name “chronic fatigue immune dysfunction syndrome” (CFIDS).

Researchers in a study of patient perspectives have argued that the earlier failure of Western medicine to demonstrate a viral etiology for ME led to a paradigmatic shift to psychiatric and sociocultural research, which effectively delegitimized ME and later CFS as a biomedical phenomenon. More accurate criteria should help to increase homogeneity and identify pathology. It has also been noted that some journals operate pro-psychiatric editorial policies, resulting in a narrow range of opinions and undermining the physicians’ understanding of the illness. A major recurrent criticism of CFS is that it does not make post-exertional malaise or muscle weakness an essential criteria thus leading to the uncertainty and controversy over the appropriatness of physical rehabilitation programmes.

ME Redux

Recent research on CFS may be relevant to ME. For example, studies have revealed pathologically delayed recovery of muscle strength, cardiac and vascular abnormalities, and defects in cellular metabolism. Neurocognitive dysfunction has been objectively observed; and physiological abnormalities relating to immune activity, gene expression, oxidative stress and the nervous system have also been found, plus many psychological and psychiatric studies have also been done. The U.S. Centers for Disease Control & Prevention (CDC) now recognize CFS as a serious illness, but also list ME as a differential diagnosis on their web site, reflecting the incompatibility of the traditional definitions.

The CFS definition allowed sufficient laxity for US specialists, including those who had preceded the CDC at Lake Tahoe, to customize the definition for those patients they thought most representative of ME.

In 2003 a group of international specialists published the consensus definition of an illness now termed “ME/CFS,” the criteria of which, including CNS and exertional signs, was more like that of ME than CFS. In January 2007 The American “CFS Name Change Advisory Board” publicized their deliberation that CFS should now be called ME, though no statement was made on definition. The CDC continue to widen their CFS definition.


* Wallis AL, “An investigation into an unusual illness seen in Epidemic and Sporadic Form in a General Practice in Cumberland in 1955 and subsequent years”, M.D. Thesis, Edinburgh University, 1957

* Acheson E (1959). “The clinical syndrome variously called benign myalgic encephalomyelitis, Iceland disease and epidemic neuromyasthenia.”. Am J Med 26 (4): 569-95. PMID 13637100.

* Goldstein JE, Hyde BM (1992). The Clinical and scientific basis of myalgic encephalomyelitis/chronic fatigue syndrome. Ogdensburg, N.Y: Nightingale Research Foundation, 628-633. ISBN 0-9695662-0-4.

* Carruthers BM, Jain AK, De Meirleir KL, Petersn DL, Klimas MD, Lerner AM, Bested AC, Flor-Henry P, Joshi P, Powles ACP, Sherkey JA, van de Sande MI (2003). “Myalgic encephalomyalitis/chronic fatigue syndrome: Clinical working definition, diagnstic and treatment protocols”. Journal of Chronic Fatigue Syndrome 11 (1): 7-36. DOI:10.1300/J092v11n01\_02.

* Gilliam AG. (1938) Epidemiological Study on an Epidemic, Diagnosed as Poliomyelitis, Occurring among the Personnel of Los Angeles County General Hospital during the Summer of 1934, United States Treasury Department Public Health Service Public Health Bulletin, No. 240, pp. 1-90. Washington, DC, Government Printing Office.

* Jason LA, Helgerson J, Torres-Harding SR, Carrico AW, Taylor RR (2003). “Variability in diagnostic criteria for chronic fatigue syndrome may result in substantial differences in patterns of symptoms and disability.”. Eval Health Prof 26 (1): 3-22. PMID 12629919.

* Jason, LA, et al., “Chronic Fatigue Syndrome: The Need for Subtypes.” Neuropsychology Review, Vol. 15, No. 1, March 2005, pp. 29-58 [PDF Format]

* Crowhurst G, “Supporting people with severe myalgic encephalomyelitis.” Nursing Standard. 19, 21, 38-43. 2005

* Goudsmit E, Stouten B, Howes S, Illness Intrusiveness in Myalgic Encephalomyelitis An exploratory study [1]