Two different strains of an alphaherpesvirus can establish latency in the same tissue of the host animal: evidence from bovine herpesvirus 1.

We inoculated plaque-purified bovine herpesvirus type 1 (BHV 1), strain K22, subtype BHV 1.2b, intravenously into susceptible cattle. Five months later, we reactivated latent virus with dexamethasone and then super-infected the same cattle intranasally and intravaginally with a different plaque-purified BHV 1, strain Cooper, subtype BHV 1.1. After a second dexamethasone treatment four months later, reactivated viruses were isolated and examined with restriction endonucleases. We showed that both virus subtypes were reactivated, proving that 2 different strains of an alphaherpesvirus can establish latency in the same tissue in the host animal.