The Epidemiology of Aseptic Meningitis and Related Nonspecific Disease in Connecticut, 1957: Virological and Clinical Studies †

The advent of modern tissue culture techniques reported in 1949 by Enders, Weller, and Robbins' initiated a new era in the study of virus infections. As a result, it has been possible to carry out systematic studies of the etiology of disease syndromes, and, to date, some seventy new agents have been isolated. It is now possible for virus isolation to contribute to the establishment of an etiological diagnosis in cases of poliomyelitis and aseptic meningitis for which previously there had been no practicable laboratory evidence of disease.1'8 The accidental discovery in tissue culture of the Echo group of viruses was followed by the demonstration that these agents are widely distributed in normal populations."" It has now become apparent that in addition to sharing epidemiological similarities with Coxsackie and polioviruses, members of the Echo group are also capable of producing characteristic disease patterns.' Not until 1954 was the association of Echo viruses with aseptic meningitis firmly established, when outbreaks associated with type 6 were described."' Subsequently type 48.18 has also been reported as cause of extensive outbreaks of aseptic meningitis. During 1956, for the first time, numerous epidemics associated with rash were reported, the etiologic agent being Echo Virus Type 9.19 In these outbreaks many associated cases of nonspecific febrile illness with rash also were reported. In Connecticut, Davis and Melnick' carried out studies covering 1955 and 1956 to determine the etiology of reported cases of aseptic meningitis