Objective To evaluate the vaccine effectiveness (VE) of varicella vaccine (VarV) in individuals aged 2–17 years in a real-world setting.

Methods On the basis of linked surveillance system data in 2024, a 1:3 individually matched case-control study design was adopted. Chi-square tests were conducted to compare distribution differences between groups. A conditional logistic regression model was employed to calculate the VE of VarV.

Results This study included 928 subjects (232 cases and 696 controls). There were differences (all P<0.001) between the case and control groups in terms of immunization history, number of doses, age at initial vaccination, and time since vaccination. The overall VE of VarV against varicella was 71.55% (95%CI: 60.26%–79.63%). The VE of one dose (VarV1) and two doses (VarV2) was 60.95% (95%CI: 41.85%–73.78%) and 76.73% (95%CI: 66.29%–83.93%), respectively. VE for initial vaccination at age of 1, 2, and ≥3 years was 71.13% (95%CI: 59.33%–79.51%), 82.15% (95%CI: 56.01%–92.76%), and 67.27% (95%CI: 37.07%–82.98%), respectively. The VE within ≤5 years, 6–10 years, and ≥11 years after the last dose was 80.93% (95%CI: 71.42%–87.28%), 66.20% (95%CI: 48.78%–77.69%), and 46.49% (95%CI: 12.57%–67.25%), respectively.

Conclusions VarV demonstrates significant effectiveness in real-world settings, with two-dose vaccination providing superior protection. However, its VE notably wanes with time since vaccination.