2024 Yes Influenza vaccine effectiveness among primary and secondary school students in Shenzhen during the 2023/24 influenza season https://doi.org/10.1080/22221751.2025.2490531 Jiang, Yawen Asia Observational Epidemiological Students Elementary (K-5) Middle/Jr High (6-8) High School (9-12) Viruses Respiratory symptoms seasonal influenza Vaccine effectiveness Primary and secondary school students Public health Test-negative case-control study This study found 57.1% influenza vaccine effectiveness among Shenzhen students in winter 2023/24. Protection was stronger for B/Victoria than A(H3N2), and effectiveness decreased with age. 2025