Herpesvirus hominis infection in newborn mice: treatment with interferon inducer polyinosinic-polycytidylic acid.

Intranasal inoculation of newborn mice with Herpesvirus hominis (HVH) type 2 provides a model for disseminated herpesvirus infections of human newborn infants. Treatment of this experimental infection with polyinosinic-polycytidylic acid [poly(I:C)] significantly increased the mean survival time and markedly altered the pathogenesis of the infection. No significant protection against final mortality was observed. Poly(I:C) therapy completely inhibited detectable viral replication in all target organs tested except the brain. In the brain there was a 2-day delay in the onset of viral replication in treated animals, which correlated with the 1- to 2-day increase in mean survival time. In general, the control of HVH replication occurred in those target organs in which poly(I:C)-induced interferon was detectable. The failure of poly(I:C) to alter the final mortality of newborn mice infected with HVH appears to be primarily due to the lack of sufficient levels of interferon induced in brain tissue and the failure to prevent viral replication in this critical target organ.