1955 Royal Free Hospital outbreak

The Royal Free Hospital outbreak was a cluster outbreak of myalgic encephalomyelitis at the Royal Free Hospital in London.

In 1955, between July and November, 292 members of the medical, nursing, auxiliary medical, ancillary, and administrative staff fell ill, of which 255 were admitted to the hospital. The disease name myalgic encephalomyelitis was coined to describe the illness.

Location
The outbreak occurred at the Royal Free Hospital, then situated at 256 Grays Inn Road, London, England, which is now the Eastman Dental Hospital. (The current Royal Free Hospital site is now in the Hampstead area of London.)

Onset
Onset involved symptoms of an upper respiratory infection, sore throat, gastrointestinal disturbances including nausea and vomiting, or acute vertigo.

Symptoms
Symptoms included:
 * Severe headache
 * Malaise
 * Lassitude
 * Vertigo
 * Pain in limbs
 * Nausea
 * Dizziness
 * Neck stiffness, neck pain
 * Pain in back
 * Myalgia, which in some patients caused them to cry out in pain, muscle weakness, cramps, twitching
 * Depression
 * Abdominal pain
 * Vomiting
 * Diplopia (double vision)
 * Tinnitus
 * Diarrhea
 * Swollen lymph nodes
 * Paraesthesia

Usually by the second or third week of the disease, there was objective evidence of involvement of the central nervous system which appeared to be characteristic of the outbreak.

Signs

 * Low-grade fever (tended to transiently occur with relapse of symptoms)
 * Swollen lymph nodes
 * Objective sensory impairment and muscle tenderness
 * Extensor plantar responses
 * Nystagmus
 * Diplopia

Findings

 * Inconsistent or normal cerebrospinal fluid
 * Electromyograms showed abnormalities of activity, but no evidence of lower motor neuron degeneration (12 of 25 abnormal. )
 * non-specific EEG abnormalities
 * Neutropenia and abnormal lymphocytes, consistent with a viral infection
 * normal or slightly elevated erythrocyte sedimentation rate
 * negative virology
 * abnormally high lactic dehydrogenase and glutamic oxaloacetic transaminase

"Evidence of involvement of the sympathetic nervous system or actual hypothalamic damage was to be found in most cases. This often took the form of orthostatic tachycardia chilliness of the extremities with increased sensitivity to cold, circulatory impairment and hypothermia."

Epidemiology
Between July 13, 1955 and November 24, 1955, 292 people, of whom the vast majority were hospital personnel, became ill. Personnel from the medical, nursing, auxiliary medical, ancillary, and administrative departments were affected. Of these two hundred fifty-five were admitted to the hospital. Despite the hospital census being near capacity, only 12 patients were afflicted.

By October 5, 1955, the hospital had to close to new admissions contain the outbreak and because of the shortage of unaffected staff. The first to report ill were a resident doctor and a ward sister. More females became ill than males, but at the time it was believed to be because of the staff's living quarters not gender, as more females than males resided at the facility.

Similar cases had occurred in the population of North West London before this outbreak and sporadic cases continued to occur after the outbreak.

Prognosis
For many patients, symptoms waxed and waned in intensity over a long period. A very large majority had complete recovery of neurological function.

Long-term follow-up
A follow-up study 65 years later found that there was one group of patients that recovered completely or nearly completely, a second group that recovered but was subject to relapses, and a third that showed little or no recovery, these patients remaining incapacitated.

Another follow-up study in 2021 interviewed former hospital staff who were present during the outbreak, and reported on their recollection of patient symptoms and circumstances at the time. Twenty-seven former hospital staff were, including a few who developed ME. The accounts of the former staff were found to be inconsistent with the McEvedy and Beard hypothesis that the illness was psychosomatic in nature, caused by mass hysteria or psychoneurosis. Observable signs of physical illness reported by the former staff included enlarged posterior cervical glands, ptosis (drooping of the eyelids), hemiparesis (one-sided paralysis), some patients crying due to extreme muscle pain, nausea, and vomiting. Patients typically delayed seeking medical treatment for the first few days, which is also inconsistent with patients overly anxious about the possibility of contracting an illness. Some patients had blood tests which found leukopenia, or lymphocytes typical of viruses. While some patients seemed to be neurotic and lacked physical signs, a large number of patients were seriously ill with significant physical signs, leading to most hospital staff at the time believing that the cause of illness was an infectious disease. Some patients remained hospitalized for over six months.

Notable studies and publications

 * 2021, Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Organic Disease or Psychosomatic Illness? A Re-Examination of the Royal Free Epidemic of 1955
 * 2020, Myalgic Encephalomyelitis (ME) outbreaks can be modelled as an infectious disease: a mathematical reconsideration of the Royal Free Epidemic of 1955
 * 2016, Is chronic fatigue syndrome finally being taken seriously?
 * 1987, Royal Free disease: perplexity continues
 * 1984, Myalgic Encephalomyelitis and Postviral Fatigue States: The Saga of Royal Free Disease, A. Melvin Ramsay, Gower Medical Publishing, London (book)
 * 1978, Epidemic myalgic encephalomyelitis (The BMJ)
 * 1978, Epidemic neuromyasthenia 1955-1978 (A. Melvin Ramsay, The BMJ)
 * 1977, Icelandic disease (benign myalgic encephalomyelitis or Royal Free disease) (A. Melvin Ramsay, Elizabeth Dowsett, J V Dadswell, W H Lyle, and J G Parish, The BMJ)
 * 1970, Epidemic malaise (Dr Betty Scott, The BMJ)
 * 1970, Epidemic malaise (N. D. Compston, H. E. Dimsdale, A. Melvin Ramsay, and A. T. Richardson, The BMJ)
 * 1970, Epidemic malaise (Dr E D Acheson, The BMJ)
 * 1970, Epidemic malaise (Dr Paula Gosling, The BMJ)
 * 1970, Epidemic malaise (Dr G J Burke, The BMJ)
 * 1970, Epidemic malaise (Dr E J Hopkins, The BMJ)
 * 1970, Epidemic malaise (Dr J F Galpine, The BMJ)
 * 1970, Epidemic malaise (Dr D C Poskanzer, The BMJ)
 * 1970, Epidemic malaise (Dr J G Parish, The BMJ)
 * 1965, Eclipse of hysteria (Dr Betty Scott, A. Melvin Ramsay, The BMJ)
 * 1965, Hysteria and 'Royal Free Disease' (A. Melvin Ramsay, The BMJ)
 * 1957, An Outbreak of Encephalomyelitis in the Royal Free Hospital Group, London, in 1955, The Medical Staff Of The Royal Free Hospital
 * 1956, An Outbreak of Encephalomyelitis in the Royal Free Hospital Group, London, in 1955, N.D. Compston

Learn more

 * Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Organic Disease or Psychosomatic Illness? A Re-Examination of the Royal Free Epidemic of 1955