Herpesvirus inoculation of cornea.

We investigated the effect of primary ocular inoculation with an avirulent herpesvirus type 1 thymidine-kinase-negative mutant on keratitis, survival, and establishment of trigeminal ganglionic latency after ocular challenge with several virulent herpesvirus type 1 thymidine-kinase-positive strains in the murine model. The effect of previous inoculation with the thymidine-kinase-negative mutant was to reduce the severity of keratitis, promote survival, and reduce the frequency of recovery of latent virus compared to the control group for all three superinfecting challenge strains. However, the thymidine-kinase phenotype (negative or positive) of recovered latent ganglionic virus or viruses disclosed incomplete protection from the previous inoculation and recovery of more than one virus strain from the same trigeminal ganglion in several mice. The success of a live, attenuated herpesvirus type 1 vaccine against ocular herpes may be limited in certain individuals by possible superinfection and secondary ganglionic colonization by wild-type herpesvirus capable of producing recurrent ocular disease.