Detection of bovine herpesvirus type 1 RNA in trigeminal ganglia of latently infected rabbits by in situ hybridization.

At times after conjunctival inoculation with bovine herpesvirus type 1 (BHV-1), representing the acute and latent phases of infection, rabbit trigeminal ganglia were examined for the presence of BHV-1 nucleic acids by in situ hybridization using a 3H-labelled BHV-1 DNA probe. During the acute phase of virus infection, both BHV-1 DNA and RNA were detected in ganglionic neurons and occasionally in adjacent satellite cells. However, during the latent phase of infection only viral RNA was detectable in involved neurons. Viral RNA appeared restricted to the nucleus of latently infected cells and was present in varying amounts in individual cells. These results indicate that the BHV-1 genome is transcriptionally active in ganglionic neurons during latent infection.