[Trend and area specific difference analysis on influenza vaccination coverage in key populations in Shandong Province, 2015-2024].

Objective: To analyze the changing trends and area specific differences in influenza vaccination coverage in key populations in Shandong Province and provide evidence for influenza prevention and control. Methods: The information about influenza vaccination in Shandong during 2015 to 2024 were collected from the Immunization Information System of Shandong Province, and the annual percentage change and average annual percentage change (AAPC) were calculated by using software Joinpoint 5.3.0. The trend of changes in vaccination coverage was analyzed and area specific differences were compared. Results: From 2015 to 2024, the influenza vaccination coverage in medical personnel ranged from 0.02% to 20.54% in Shandong (AAPC=63.24%, 95%CI: 51.37%-100.65%), showing a rapid increase from 2015 to 2020 (P<0.001) and a stead decrease from 2020 to 2024 (P=0.008). The vaccination coverage in teachers and students ranged from 1.51% to 6.88% (AAPC=12.33%, 95%CI: -0.97%-36.27%), with a monotonic increase from 2015 to 2024 (P=0.070). The vaccination coverage in elderly people aged ≥60 years ranged from 0.03% to 11.68% (AAPC=102.65%, 95%CI: 64.16%-208.69%), with a rapid increase from 2015 to 2017 (P<0.001), a steady increase from 2017 to 2020 (P<0.001), and a slower increasee from 2020 to 2024 (P=0.046). There were area speciific differences in the temporal trend of influenza vaccination coverage. Compared with areas with low gross domestic product (GDP), the areas with high and medium GDP had significantly higher vaccination coverage and increase rates. Conclusions: The influenza vaccination coverage in key populations showed an upward trend in Shandong from 2015 to 2024, and the vaccination coverage in elderly people aged ≥60 years increased significantly. However, it is important to increase vaccination coverage in areas with low GDP and in teachers and students.