Safety profile of herpes zoster vaccines in the United States: a descriptive and disproportionality analysis of adverse events reported to the vaccine adverse event reporting system (VAERS), 2017-2024.

BACKGROUND

Herpes zoster causes substantial morbidity in older adults, and US herpes zoster vaccination shifted from the live-attenuated Zostavax to the recombinant Shingrix after 2017 We describe the post-marketing adverse-event profile of these vaccines reported to the US Vaccine Adverse Event Reporting System (VAERS) and identify events reported disproportionately for herpes zoster vaccines.

METHODS

In a descriptive cross-sectional design, we analyzed 69,822 US VAERS reports listing a herpes zoster vaccine, received 1 January 2017-25 April 2024. Reports were characterized by demographics, brand, MedDRA preferred terms and system organ classes, and US FDA serious-event indicators; brand subgroups were summarized descriptively. Reporting odds ratios (RORs) with 95% confidence intervals compared the combined herpes zoster vaccine cohort with all other US VAERS reports. Reporting followed the STROBE guideline.

RESULTS

Shingrix accounted for 58,813 (84.2%) reports and Zostavax for 10,507 (15.0%). Reports were predominantly in women (63.9%) and adults aged 50-69 years (median age 64.0 years). Reactogenic and injection-site terms predominated-pyrexia (18.3%), pain (17.8%), chills (15.9%), headache (15.4%), and injection-site pain (14.2%). Against all other US reports, injection-site and influenza-like reactions were modestly enriched (e.g., injection-site pain ROR 2.92), whereas vesicular rash was strongly over-reported (ROR 43.70); the latter was concentrated in live-vaccine reports and reflects reported vaccine-strain disease rather than an unexpected adverse reaction. Serious reports comprised 6.6% of the cohort (2.9% Shingrix, 27.6% Zostavax).

CONCLUSION

Eight years of VAERS data are consistent with the recognized reactogenicity of the recombinant vaccine and the live-vaccine profile of Zostavax; most reported events were transient and non-serious. These hypothesis-generating disproportionality signals require confirmation in active surveillance with denominator data.