Varicella-zoster virus-specific immunity after herpes zoster.

The frequency of varicella-zoster virus (VZV)-specific T lymphocytes was higher in elderly subjects who had herpes zoster infections than in age-matched controls. This increase in T cell response persisted for at least 2 years while antibody levels to VZV returned to control values at this time. There were no differences in T cell or antibody responses to VZV between individuals with and without postherpetic neuralgia. Elderly subjects who had not had herpes zoster had a comparable increase in VZV-specific T responder cell frequency after immunization with Oka strain VZV. The data suggest that the potential for a boost in T cell response to VZV persists in the elderly, and that immunization can elicit a T cell response in this age group.