Vaccines are cornerstones of public health, yet equitable access remains a major global challenge. While China has achieved sustained high coverage of National Immunization Program (NIP) vaccines, some WHO-recommended cost-effective non-NIP vaccines, such as Hib, pneumococcal conjugate (PCV), rotavirus, and human papillomavirus vaccines (HPV) are not universally accessible and often require out-of-pocket payment. This study examines geographic and urban–rural disparities in the availability of these four vaccines across China using data from a nationally representative China’s National Health Accounts survey in 2022, covering 355 district- and county-level disease control centers and 2,609 public primary health facilities across 27 provinces. Availability was defined as the presence of at least one dose delivered or administered. Inequality was assessed using Slope Index of Inequality (SII) and the Erreygers-corrected Concentration Index (CI), based on provincial GDP per capita. We found significant disparities in vaccine availability across economic development levels and urban–rural settings in China. Overall, HPV vaccines were most available (96.9%) and PCV13 the least (86.5%) at the district/county level. Urban areas had markedly higher availability than rural areas, particularly for PCV13 (94.2% vs. 79.1%). At the clinic level, over 70% of urban clinics provided all four vaccine types, compared to just 40% in rural areas. The vaccines with the highest inequality were DTaP-IPV-Hib (CI: 0.408), PCV13 (CI: 0.362), and RV5 (CI: 0.343), indicating strong pro-rich distribution. In contrast, the Hib vaccine demonstrated the lowest inequality (CI: 0.209). These findings highlight significant inequities in the availability of WHO-recommended non-NIP vaccines across China, particularly affecting rural and economically disadvantaged regions underscoring the need of expanding vaccine provision in underserved areas, strengthening rural service capacity, and considering the inclusion of these vaccines in the NIP.

Objectives: This study aimed to investigate the protective effect of the Changchun Baike varicella vaccine in Yanji City from 2018 to 2024. Methods: Varicella surveillance data from 2018 to 2024 and vaccination records from 2018 to 2020 were collected from the China Disease Prevention and Control Information System and analyzed. Results: In total, 2452 varicella cases were reported in Yanji from 2018 to 2024, with an average annual incidence rate of 62.71 per 100,000 population. Notably, the annual incidence rate decreased from 142.37 per 100,000 in 2018 to 55.25 per 100,000 population in 2024. Additionally, the highest and lowest incidence rates were observed in the 10–14 and ≥40 years age groups, respectively. Moreover, the vaccine demonstrated high protective effectiveness of 98.0–99.0% for one dose and 99.0% for two doses across the study period. These estimates were derived from propensity score-matched cohorts ranging from 686 to 6990 individuals (343 to 3495 matched pairs) across three overlapping observation periods (2018–2022, 2019–2023, and 2020–2024). Conclusions: The two-dose varicella vaccination schedule demonstrated superior protective efficacy compared with the single-dose schedule.

Background: Varicella burden is closely linked to national socioeconomic development, yet systematic analyses of its non-linear relationship with the Socio-demographic Index (SDI) are lacking. This study aims to elucidate this relationship and inform equitable, context-specific strategies. Methods: Based on data from the Global Burden of Diseases 2021 study, we analyzed global trends (1990–2021) in the incidence, prevalence, mortality, and disability-adjusted life-years (DALYs) of varicella. Joinpoint regression was used to identify trend transition points, and an autoregressive integrated moving average (ARIMA) model was applied to forecast the disease burden through 2035. Analyses were conducted, and countries and territories were stratified into five SDI groups: high (SDI > 0.81), high–middle (0.70–0.81), middle (0.61–0.69), low–middle (0.46–0.60), and low (SDI < 0.46). These approaches aimed to systematically elucidate the socioeconomic gradient of the varicella burden and to specifically investigate its potential non-linear relationship with SDI. Results: From 1990 to 2021, global age-standardized mortality and DALYs declined by −45.71% (95% UI: −48.32% to −42.95%) and −36.15% (95% UI: −39.04% to −33.01%), respectively, while incidence and prevalence rates slightly increased. A significant U-shaped relationship emerged between burden and SDI, with rates highest in low- and high-SDI regions. The rise in high-SDI regions was driven by increasing incidence and prevalence from 1996 to 2015. Projections to 2035 indicate continued global decline but persistent disparities. Conclusions: The varicella burden follows a U-shaped socioeconomic gradient. Rising incidence in high-SDI regions highlights that economic development and routine pediatric vaccination alone are insufficient. Precision strategies tailored to SDI levels—closing adult immunity gaps in high-SDI, sustaining gains in middle-SDI, and expanding vaccine access in low-SDI regions—are essential.

This study aimed to investigate the protective effect of Changchun Baike varicella vaccine in Yanji City from 2018 to 2024. Varicella surveillance data from 2018 to 2024 and vaccination records from 2018 to 2020 were collected from the China Disease Prevention and Control Information System and analyzed. In total, 2,452 varicella cases were reported in Yanji from 2018 to 2024, with an average annual incidence rate of 62.71 per 100,000 population. Notably, the annual incidence rates decreased from 142.37 per 100,000 in 2018 to 55.25 per 100,000 population in 2024. Additionally, the highest and lowest incidence rates were observed in the 10–14 and ≥ 40 years age groups, respectively. Moreover, Changchun Baike varicella vaccine showed protective efficacies of 98.0–99.0% and 99% for the first and second doses, respectively, from 2018 to 2024. Importantly, the two-dose varicella vaccination schedule demonstrated superior protective efficacy compared with the single-dose schedule.