Reye syndrome associated with vaccination with live virus vaccines. An exploration of possible etiologic relationships.

To determine whether vaccination with live virus vaccines may be etiologically related to Reye syndrome, we examined 404 cases reported to the Center for Disease Control. Fifteen of 269 children with Reye syndrome has been inoculated with live virus vaccines within 30 days before onset of illness. Although this temporal relationship may have occurred by chance, seasonal distribution and clustering of incubation periods suggests that live virus vaccines may occasionally serve as cofactors in the etiology of Reye syndrome through undefined mechanisms.