A community-based survey of varicella-zoster virus-specific immune responses in the elderly

Abstract Background In the USA, live attenuated varicella-zoster virus (VZV) vaccine is licensed for use in people 50 or older, to reduce the incidence and/or severity of herpes zoster. However, this vaccine is not yet available in Japan, and the immunity profile for VZV in older people has not been investigated in detail in Japan. Objectives The aim of this study was to conduct a detailed survey about the immunity profile for VZV in older people in Japan. Study design A panel of immunologic tests (skin test, ELISPOT, gpELISA, IAHA and NT) were used to analyze the immunity to VZV in the subjects. And an interview about zoster history was carried out with each of the subjects. Results Cellular immunity test (skin test and ELISPOT) results declined with increasing age; on the contrary, humoral immunity test (gpELISA, IAHA and NT) results increased with advancing age. In addition, strongly boosted humoral immunity was found in the subjects with zoster history, however relatively small increase was found in cellular immunity test results. Conclusions Cell-mediated immunity (CMI) to VZV decreased and humoral immunity increased with increasing age in this population.