does it work?
well yeah apparently - from cdc usa
Vaccine Efficacy
In a clinical trial involving more than 38,000 adults 60 years of age or older, the vaccine reduced the overall incidence of shingles by 51% and the incidence of PHN by 67%. The efficacy of the vaccine in preventing shingles was higher in the younger age group (60-69 years; vaccine efficacy was 64%) than in the older age group (older than 70 years; vaccine efficacy was 38%).
Studies are ongoing to assess the duration of protection from one dose of zoster vaccine and the need, if any, for booster doses.