1953 Maryland outbreak

1953 Maryland outbreak: In July, 1953, a sudden outbreak of a polio-like infection occurred in the student nurses at Chestnut Lodge Hospital, a private, psychiatric hospital in Rockville, Maryland, near Washington, DC.

The Montgomery County Health Department, the Maryland State Health Department, National Institute of Allergy and Infectious Diseases, and Georgetown University School of Medicine were involved in deciphering the outbreak. The investigators later stated in an article for the New England Journal of Medicine: "In a typical severe case the early manifestations included localized muscular weakness, stiffness of the neck and back, headache, diarrhea and temperature elevation. Within a few days it became apparent that the epidemiologic features and the course of the illness were not compatible with poliomyelitis and that we were dealing with an entity unknown to us." The outbreak was deemed to resemble other outbreaks of poliomyelitis-like illnesses in hospitals around the same time, including the Los Angeles County Hospital in 1934. Epidemic neuromyasthenia became the final diagnosis.

Fifty cases were documented; 48 females and 2 males, of which 47 of the cases were in the student nurse population. Lumbar puncture were done on 25 of the cases and all 25 were negative for cerebral spinal fluid involvement. Eight lumbar were repeated and all of those were negative, also.

In 1970, this outbreak was one of fifteen mentioned in a paper by psychiatrists Colin McEvedy and A. W. Beard, who wanted to renamed all fifteen outbreaks as mass hysteria or myalgia nervosa. The psychiatrists were criticized by patients and researchers, such as Dr. Melvin Ramsay who were directly involved in the outbreak. McEvedy admitted to Dr. Byron Hyde, when invited to discuss his theory, that he did not examine any patients and undertook only the most cursory examination of medical records.