encephalomyelitis chronic fatigue syndrome myalgic encephalomyelitis http://purl.bioontology.org/ontology/MEDDRA/10028414 A disease given its first diagnostic criteria in 1986: (1) muscle fatiguability in which, even after minimal physical effort, three or more days elapse before full muscle power is restored; (2) extraordinary variability or fluctuation of symptoms, even in the course of one day; and (3) chronicity. Signs of encephalomyelitis were considered to be one of the symptoms noted in the 1950s. ME myalgic encephalomyelitis/chronic fatigue syndrome