Prepubertal vaccination of mice against experimental infection of the genital tract with type 2 herpes simplex virus.

Pre-pubertal immunisation of mice with a formalin-inactivated type 1 and 2 herpes simplex virus vaccine conferred a level of life-long protection against primary type 2 genital infection. Protection levels were better with type 1 vaccine and strikingly influenced by vaccine dosage where a one-hundred-fold reduction from the standard vaccine dosage diminished protection to insignificant levels. Vaccine efficacy was not significantly affected by the method of virus inactivation, the number of immunisations or the age of the mouse at immunisation. Vaccination conferred better protection than previous type 2 genital infection; this may be a consequence of a higher antigenic dose, more acceptable antigenic presentation or to a perversion of the immune response in a latently infected animal to homologous virus challenge.