Aseptic meningitis in infants < 2 years of age: diagnosis and etiology.

Standard virologic methods were used to characterize the relative contribution of each of the enterovirus classes to the etiology of aseptic meningitis during a prospective study of this disease among children < 24 months old. Viruses were isolated in cell culture from 164 (60%) of 274 cases identified over 5 years and in newborn mice from only 2 of 104 remaining cell culture-negative cases. Serologic tests identified the viral pathogen in 3 additional cases. The group B coxsackieviruses and the echoviruses were implicated in 156 (92%) of the 169 laboratory-diagnosed cases. Forty-eight percent of all diagnosed cases were due to group B coxsackievirus serotypes 2, 4, and 5; 78% of all cases were attributable to only 8 of the 67 known enterovirus serotypes. Polioviruses were the only viruses isolated from 7 children, including a cerebrospinal fluid isolate from 1 child and a urine isolate from another. Disease was attributable to the group A coxsackie-viruses for only 3 cases.