BackgroundThe live attenuated varicella-zoster virus (VZV) vaccine is used for the prevention of chickenpox and herpes zoster; however, there have been few studies on the immunogenicity of intradermal vaccination. ObjectiveTo compare the immunogenicity between subcutaneous and intradermal VZV vaccination. MethodsThirty healthy participants aged 50–75 who developed erythema less than 10 mm in diameter in VZV skin test were examined. Thirteen participants received full dose of VZV vaccine subcutaneously and 17 participants received one-fifth dose of vaccine intradermally. Immunogenicity to VZV was determined by VZV skin test reaction, proliferation of VZV-specific memory T cells, levels of VZV-specific serum antibody, and cytokine production from peripheral blood cells. ResultsVZV skin test reaction was similar between two groups. VZV-specific memory T cells were significantly increased only in the intradermal injection group. The increase of VZV-specific memory T cells correlated with Th1, Th2 and Th17 cytokines and cytotoxic molecules. No serious adverse events were observed in either group after vaccination. ConclusionIntradermal injection with one-fifth dose VZV vaccine showed a similar or greater effect on VZV-specific cellular immunostimulation than conventional subcutaneous injection. These findings suggest that one-fifth dose intradermal vaccination may have a comparable preventive effect to conventional subcutaneous injection.