Post-Marketing Surveillance of Adverse Events Following Recombinant Zoster Vaccine - China, 2020-2023.

Objective: To assess adverse events following recombinant zoster vaccine (RZV) in China during the post-marketing period. Methods: The study obtained data on adverse events following immunization (AEFI) and vaccination doses of RZV from the Chinese National Immunization Information System (CNIIS). We analyzed RZV AEFI reports from 2020 through 2023. Results: During the study period, 1.99 million doses of RZV were administered, and 10,525 RZV AEFI cases were reported. The reporting incidence of AEFI was 527.76 per 100,000 doses administered, with serious AEFI at 0.55, common vaccine reactions (usually minor) at 518.19, and rare vaccine reactions (possibly serious) at 4.06 per 100,000 doses. Among adverse vaccine reactions, the most frequently reported common vaccine reactions were fever (333.76/100,000) and local redness and swelling (213.51/100,000), while the main reported rare vaccine reaction was allergic rash (3.01/100,000). Conclusions: Most RZV AEFIs were common vaccine reactions, consistent with adverse events reported in RZV clinical trials. The incidence of rare vaccine reactions was very low, and most of which were allergic rash. No special safety concerns were identified and AEFI surveillance should be continued.