The epidemic of encephalitis occurring in St. Louis and Kansas City during the summer of 1933 differed in a number of clinical and epidemiologic characteristics from the majority of previously reported epidemics. Since it is probable that these differences may be the result of different causative agents, no attempt will be made to review the voluminous and conflicting literature on the etiology of encephalitis, and this paper will be limited strictly to studies on the disease occurring in epidemic form in the recent outbreak.
Investigations into the etiology of the 1933 outbreak of encephalitis may be said to have begun before the nature of the disease was recognized or the onset of an epidemic was suspected. When the first few cases were admitted to the St. Louis County Hospital, the nature of the febrile illness was not immediately appreciated, and many cultures of blood and spinal fluid were made, as
MUCKENFUSS RS, ARMSTRONG C, WEBSTER LT. ETIOLOGY OF THE 1933 EPIDEMIC OF ENCEPHALITIS. JAMA. 1934;103(10):731-733. doi:10.1001/jama.1934.02750360007004