Fact box: The mysterious disease at the Royal Free Hospital 1955
  
292 persons of the Royal Free Hospital staff in London, principally administrators, physicians and nurses, were taken ill between July 13 and November 24 1955. Although the hospital was almost full, only 12 patients were afflicted. The initial symptoms were malaise, headache, depression, emotional instability and a mild sore throat. Approx. three weeks later came the more typical phase with ache in the nape of the neck, the back and the arms and legs, plus dizziness. 74 percent of those afflicted showed neurological symptoms as well, such as blurred vision and muscle twitches.

Dr. Melvin Ramsay was a consultant physician at the Infectious Diseases Department of the Royal Free Hospital, and he also served as advisor to the Ministry of Health in matters concerning smallpox. He coined the expressions post-viral fatigue and benign myalgic encephalomyelitis for this condition, which had manifested itself also by a few earlier outbreaks during that same year, in other parts of England. Today still, there are many who regard this as an example of mass hysteria (see, for instance, Geoff Watts, "All in the mind", New Scientist 28 June 2002).

Dr. Ramsay, who treated several hundred patients of this kind, was, however, at an early stage convinced that this was not just figments of overheated minds. The symptoms were similar to the aftereffects of virus infections, such as Coxsackie or Epstein-Barr. In addition, hysteroid symptoms would hardly prevail for decades, which was the case with many of the afflicted:

"I am now in no doubt that ME is an endemic disease which is subject to periodic outbreaks of an epidemic kind. [...] Correspondence began to build up with doctors in the United States, Australia and New Zealand who were encountering similar problems. Many of these sufferers were doctors themselves or their wives. [...] The patients whom Dr Scott and I saw came to us in a state of utter despair, their medical advisers finding themselves baffled by a medley of symptoms which they were unable to place into any recognizable category of disease. Without exception, these patients had been referred for consultant opinion and they were generally seen by neurologists who were equally nonplussed, having found no abnormality on physical examination and with extensive laboratory investigations failing to yield a clue. I must add, however, that in no case had any investigation of the immune system been carried out. Many of these patients were finally referred for psychiatric opinion and it is interesting that four psychiatrists to my knowledge referred patients back with a note which in essence said 'I do not know what this patient is suffering from, but the case does not come into my field'. For the most part these unfortunate people were finally rejected as hopeless neurotics and there was at least one instance of a family breaking up when five doctors assured the husband that there was nothing wrong with his wife; she is now a chronic ME sufferer with permanent physical incapacity."

Melvin Ramsay, "Post-viral fatigue: The saga of the Royal Free Disease", 1984.