1934 Los Angeles atypical polio outbreak

The 1934 Los Angeles County Hospital epidemic is the first known recorded cluster outbreak resulting in what is now known as myalgic encephalomyelitis.

Between May 1934 and December 15, 1935, one hundred ninety-eight (198) employees of Los Angeles County Hospital came down with an acute onset neurological illness, including about 10.7% of the nurses and 5.4% of the physicians. As a poliomyelitis epidemic was occurring in California at this time, the first impression from the medical community was that the illness was polio, especially since the the illness presented with similarities including sharp febrile onset and flaccid weakness.

In short time, striking deviations from polio began to emerge in five areas:
 * the relatively high attack rate (4.4% of all employees fell ill compared to the incidence of 0.07% of polio in the Los Angeles community);
 * fatality rate (there were 0 deaths compared to a 1.39% fatality rate with polio);
 * low paralytic rate, both in terms of weakness at any time or in residual paralysis (an estimate of 7% of polio cases resulted in residual paralysis in the Los Angeles community)
 * high transmission rate/communicabilty;
 * age selection of adults (only adults were afflicted, whereas, polio is predominantly a childhood disease, with the highest incidence in those under six years of age)

Publications

 * Epidemiological Study Of An Epidemic, Diagnosed As Poliomyelitis, Occurring Among The Personnel Of The Los Angeles County General Hospital During The Summer Of 1934 - ''Public Health Bulletin no.231-240 1936-1938 By: A.G. Gilliam
 * Observations On The Epidemic Of Polio-Encephalitis In Los Angeles, 1934* - California And Western Medicine By: E.C. Rosenow, MD; F.R. Heilman, M.D.; and C.H. Pettet, M.D.
 * Poliomyelitis-The Los Angeles Epidemic of 1934* - Western Journal of Medicine By: R.W. Meals, MD; Vernon F. Hauser, MD; and Albert G. Bower, MD
 * Use of Serum and the Routine and Experimental Laboratory Findings in the 1934 Poliomyelitis Epidemic* - American Public Health Association By: John F. Kessel, Anson S. Hoyt and Roy T. Fisk

Newspaper articles

 * Los Angeles Polio Epidemic Decreases - Madera Tribune, Number 55, 6 July 1934
 * Infantile Paralysis Development Shown - Madera Tribune, Number 58, 10 July 1934  Editor's Note:  This article reveals that persons over the age of 20 were being described as having "Infantile Paralysis".
 * Infantile Paralysis Outbreak Not Serious - Madera Tribune, Number 55, 6 July 1934
 * Infantile Paralysis Peak Reported Passed - Madera Tribune, Number 56, 7 July 1934
 * Real Heros of Paralysis Epidemic - Healdburg Tribune, Number 290, 11 October 1934    Editor's Note:  GREAT PHOTOGRAPH OF SICK NURSES!

Learn more

 * Los Angeles County Hospital, Wikipedia