Limited transcription of the herpes simplex virus genome when latent in human sensory ganglia.

Human paravertebral ganglia were examined for the presence of specific sequences of viral RNA by in situ cytological hybridization, using as probes individual fragments of herpes simplex virus type 2 DNA. Ganglia were obtained at autopsy from 40 patients, and 14 were positive for herpes simplex virus RNA. Transcripts from the left-hand 30% of the viral genome were detected in all of the herpes simplex virus-positive cases. RNA homologous to other sequences from the L component were present less frequently, and no RNA from the S component was detected. These results argue that specific transcription of the herpes simplex virus genome occurs in latently infected human ganglion cells.