Influenza vaccination coverage of population and the factors influencing influenza vaccination in mainland China: A meta-analysis

Introduction: The best way to prevent influenza is receiving vaccination. However, the influenza vaccination coverage in mainland China was low. A meta-analysis was conducted to estimate the vaccination rates of the population and the factors influencing influenza vaccination in mainland China. Methods: A systematic study was conducted on March 18, 2018, using Chinese language databases including China National Knowledge Infrastructure, Chinese Science and Technology Periodical Database, WanFang Database, and English language databases including PubMed, Web of Science, and Cochrane Library. Based on the inclusion and exclusion criteria, the pooled coverage rate and estimated odds ratios (OR) of influencing factors were obtained using data abstraction. Subgroup analysis and meta-regression analysis were also employed to explore the heterogeneity. Results: The pooled vaccination coverage rate in 126 included articles was 23.2% (95% confidence interval (CI): 22.8%, 23.7%), and the pooled vaccination rate among the general population was 9.4% (95% CI: 8.0%, 10.9%). The influenza vaccination rate fluctuated from 2005 to 2017. Vaccination rates in 2009-2010 were much higher than other years, pandemic influenza vaccination rate was 37.3% (95% CI: 28.4%, 46.1%) and seasonal influenza vaccination rate was 29.8% (95% CI: 24.6%, 34.9%). In the analysis of influencing factors, those recommended by healthcare workers was the most reported reasons for influenza vaccination with an OR = 5.2 (95% CI: 2.9, 9.4), and following as received influenza vaccination previously, perceived safety of vaccination, perceived effectiveness of vaccination, perceived severity of the disease. Meta-regression analysis indicate that the heterogeneity maybe significantly consistent with the sample size, study population, study region, and vaccination policy. Conclusion: Compared with other countries (the United States), vaccination rates were lower in mainland China. There were a few factors influencing the rate, which included vaccination policy, vaccination history and knowledge and attitudes toward influenza and vaccination.