Analysis of Key Factors and Equity in Influenza Vaccination among Chinese Adults-Evidence from a Large National Cross-Sectional Survey

Dong Bo¹Zhi hao Lei^2,3Menghan Jiang⁴Yue Han^5*

• ¹School of Public Health, Zhejiang Chinese Medical University, Hangzhou, Jiangsu Province, China
• ²School of Mathematics, University of Edinburgh, Edinburgh, Scotland, United Kingdom
• ³Department of Biostatistics, Brown University, Providence, United States
• ⁴School of Humanities and Management, Zhejiang Chinese Medicine University, hangzhou, China
• ⁵960 Hospital of the Chinese People's Liberation Army, Jinan, Shandong Province, China

Influenza is prevalent globally, leading to severe morbidity and mortality. Vaccination remains a critical strategy for influenza prevention. Although previous studies in China have primarily focused on influenza vaccination among children, limited research has addressed the key determinants and equity issues concerning adult influenza vaccination. This study is the first to examine the key factors influencing adult influenza vaccination and its equity using data from the nationally representative Chinese General Social Survey. Results showed that the influenza vaccination rate among Chinese adults is low (6.75%). Key factors identified as influencing adult vaccination include government trust, physician trust, income, aging concerns, health insurance, age, education, and health status. These factors not only have independent effects but also interact to influence vaccination behavior. Regarding individual effects, government trust, physician trust, income, and aging concerns showed positive associations with vaccination rates. Conversely, health insurance status, age, educational attainment, and health status demonstrated negative associations. Regarding the interaction terms, there were positive associations between health insurance and government trust, education and government trust, health and physician trust, government trust, as well as education level and age with the target variables. In contrast, interactions between income and health insurance, as well as income and physician trust negatively influenced vaccination rates. The concentration index for adult influenza vaccination was 0.092. There was inequity in vaccination, with the distribution of vaccinations being skewed toward higher-income individuals. Decomposition analysis further revealed that the primary contributors to vaccination inequity, in descending order of magnitude, were income (32.6%), government trust (9.1%), education (8.7%), age (8.2%), and aging concerns (2.6%). To improve adult influenza vaccination rates and promote vaccination equity, it should be noted to emphasize building trust, subsidizing vaccination costs, and implementing comprehensive, targeted interventions..