STUDY DESIGN: Double center, open label study in which adult healthy volunteers will be vaccinated with Zoster vaccine. Blood samples will be collected on day D-30 (pre- vaccination) D0 (at vaccination) and D1, D3, D7, D14, D30, D90 and D180 (post vaccination) to study innate and adaptive immunity responses. Even though Zoster vaccine is considered safe, volunteers are asked to report and record any local or systemic AEs for 7 days post-vaccination. Also AEs will be reported for 30 days post-vaccination any SAE for 180 days post vaccination. AEs developing the day of the blood draw will also be reported