Newborn rats were injected intraperitoneally with uninfected human cells or cell infected with 56,000 pfu of varicella-zoster virus (VZV). Five to 6 weeks later, trigeminal ganglia were harvested and tested for VZV DNA and RNA by PCR. VZV gene 21 and 40 DNA were detected in most infected animals. Gene 21 RNA also was detected in ganglia from most infected animals, but not gene 40 RNA, paralleling previous observations in latently infected human ganglia. The neonatal rat may represent a useful new model for the study of VZV latency.