Declining Effectiveness of Herpes Zoster Vaccine in Adults Aged ≥60 Years

Abstract

Understanding long-term effectiveness of herpes zoster (HZ) vaccine is critical for determining vaccine policy. 176 078 members of Kaiser Permanente ≥60 years vaccinated with HZ vaccine and three matched unvaccinated members were included. Hazard ratios and 95% confidence intervals (CIs) associated with vaccination at each year following vaccination were estimated by Cox regression model. The effectiveness of HZ vaccine decreased from 68.7% (95% CI, 66.3%-70.9%) in the first year to 4.2% (95% CI, -24.0% to 25.9%) in the eighth year. This rapid decline in effectiveness of HZ vaccine suggests that a revaccination strategy may be needed, if feasible.

Background paper to the decision not to recommend a standard vaccination with the live attenuated herpes zoster vaccine for the elderly in Germany

“…To examine the long-term protection provided by the vaccine, a follow-up study was initiated with the same study cohort, using the identical study design for a period of 8 years [40,41]. 176,078 subjects who received the vaccination between January 2007 and December 2014 at the age of ≥60 years were compared to 528,234 non-vaccinated persons at a ratio of 1:3.…”

“…For this issue it was therefore necessary to combine the results from the SPS study and its follow-up studies (STPS and LTPS) (36,38,39) and to take into account the results of the post-marketing study with members of the Kayser Permanente [41]. The results of the longterm observations show, that the HZ vaccine provides only short term protection against HZ.…”

Clinical and economic impact of herpes zoster vaccination in elderly in Italy

“…Applying a wane rate of protection in the time equal to that reported by Tseng et al 4 to the vaccine efficacy data for both HZ and PHN, the simulation model has calculated the results shown in Table 5.…”

“…Loss of protection over the time. The study by Tseng et al 4 showed the decline and then the loss of vaccine efficacy against HZ in 8 years. At present, however, no data are available on loss of efficacy against PHN.…”

“…At present, however, no data are available on loss of efficacy against PHN. In this scenario, then, the percentage of reduction reported by Tseng et al 4 has been applied to the vaccine efficacy against HZ reported in the clinical trials. It has been hypothesized a parallel loss of protection also for the vaccine efficacy against PHN.…”