Epidemiology and Seroimmunological Studies on Aseptic Meningitis

One hundred and fifty-five patients with aseptic meningitis syndrome were investigated serologically, virologically and epidemiologically in Kyoto and Matsuzaka during the peiod 1959-1963. Laboratory procedure included attempts to isolate enteroviruses from stools and cerebrospinal fluid, and antibody determinations for Polio, ECHO, Coxsackie group B, Mumpsm Adeno, and Japanese encephalitis viruses. Cases of aseptic meningitis were encountered mostly in summer, as expected. Males moderately outnoubered females, as generally reported. Age distribution showed a peak in childhood and early school age. Aseptic meningitis showed diverse etiologies, associated most frequently with Polio, ECHO, Coxsackie group B and Mumps viruses. A viral etiology could be established for 65.7% and 70.7% in Kyoto, and 83.9% in Matsuzaka with serological techniques employed. It was shown that 25 strains of enteroviruses, including Poliovirus type I, ECHO virus types 4, 6, 7 and 14, Coxsackie group B virus types 2, 3 and 5, were recovered from stools of patients. Only one strain of ECHO virus type 7 was isolated from cerebrospinal fluid. Comparison of cases of aseptic meningitis during the period 1959-1961, before the administration of Polio vassine, with the cases during the period 1962-1963, after administration, was made. In the former, Poliovirus played a leading role as an agent of aseptic meningitis, but in the latter, the association of Poliovirus was not demonstrated. And no evidence was found that Polio mass vaccination might have any influence upon the other virus patterns.