Editor’s Note:
Each year, as autumn and winter arrive, influenza viruses return as expected, which poses a threat not only to individual health but also places a significant burden on public health systems. Vaccination remains the most effective and cost-efficient means of preventing influenza and its severe complications.
As the flu season approaches, we will release two special weekly series featuring summaries of scientific evidence, implementation experiences, and intervention practices related to influenza vaccination—primarily based on China’s domestic research and field data. This series aims to provide useful references for disease control and public health authorities in strengthening influenza vaccination programs, health education, and policy advocacy.
Intervention and Implementation Strategies
1. Immunization strategies and services
01
Government Public Welfare Initiative: The Zhejiang Province Case of Free Influenza Vaccination for Older Adults
Since 2020, Zhejiang Province has incorporated free influenza vaccination for adults aged 70 years and above into its provincial-level public welfare program, with some areas extending eligibility to those aged 60 and above. By 2024, the program had achieved full coverage across all districts and counties, benefiting a total of 1.9 million older adults, with a satisfaction rate exceeding 99%.
Haiyan County, one of the earliest pilot regions, began implementing the program in 2019. It adopted a three-tier grid-based mobilization model—led by the government and coordinated through health authorities at the township (or subdistrict), administrative village (or community), and village group leader levels—to ensure efficient organization and outreach. This structure enabled the target population coverage to expand steadily year by year.
From 2019 to 2023, the influenza vaccination rate among adults aged 60 and above in Haiyan County reached 61.0%, significantly higher than the provincial average of 36.4% during the same period. The success of the program can be attributed to scientific planning, interdepartmental collaboration, grassroots mobilization through local networks, and the integration of digital tools, offering a model that is both scalable and replicable for other regions.
https://doi.org/10.3389/fpubh.2025.1571499
02
Preferences and Determinants of Adult Vaccination Site Selection: A Cross-Sectional Study Across 30 Provinces in China
Participants in this study generally preferred vaccination sites that offered high convenience, efficient service, transparent pricing, and a comfortable environment. Adults aged 35–44 years, those with a monthly income above CNY10,000, and individuals who had previously received vaccines other than the COVID-19 vaccine were more likely to choose community health service centers as their preferred vaccination location.
The patterns of site preference were consistent across different vaccines, including influenza, herpes zoster, and pneumococcal vaccines, with the majority of participants favoring community health service centers for vaccination services.
Satisfaction analysis revealed that individuals who had previously received an influenza vaccine reported higher satisfaction with appointment systems, waiting times, and service hours compared with those who had not been vaccinated.
Multivariate analysis of vaccination decision factors showed that individuals who perceived influenza vaccination as important, were less concerned about service costs, valued convenience, and followed physicians’ recommendations were more likely to receive the influenza vaccine.
https://doi.org/10.1080/21645515.2024.2442104
03
Increasing Childhood Influenza Vaccination Coverage Reduces Influenza Cases Across All Age Groups: An Agent-Based Modeling Study
Raising influenza vaccination coverage among school-aged children can significantly reduce influenza infections and hospitalizations across the entire population. The study found that for every 5% increase in vaccination coverage among school-aged children, influenza cases in this group decreased by 3.2%, while overall population cases declined by 3.3%. When vaccination coverage increased by 15%, influenza cases dropped by 10.9% among children and 11.6% across the total population. The study identified two key mechanisms driving this effect: First, children serve as major transmission nodes for the influenza virus, and improving their immunity effectively disrupts transmission chains. Next, the use of the trivalent live attenuated influenza vaccine (LAIV3) may provide higher protective efficacy compared with the traditional quadrivalent formulation (LAIV4).
International experience: https://doi.org/10.1016/j.jinf.2025.106443
2. Healthcare Workers
01
Current Status, Willingness, and Influencing Factors for Influenza Vaccine Prescription Among Chinese Healthcare Workers
A nationwide cross-sectional survey was conducted via the expert consultation platform of the 2024 World Influenza Congress (July 3–10, 2024). Among hospital healthcare workers, 68.8% (778/1131) reported willingness to prescribe influenza vaccines, compared with 61.9% in community healthcare settings.
Analysis of influencing factors indicated that healthcare workers with a history of influenza vaccination were more likely to provide vaccine prescriptions (adjusted odds ratio [aOR] = 0.30, 95% CI: 0.23–0.39, P < 0.001). Incentive mechanisms, including monetary bonuses and integration into monthly/annual performance evaluations, significantly increased prescription willingness. Regarding vaccine promotion strategies, 63.4% of healthcare workers considered WeChat public account notifications the most effective way to enhance public awareness of vaccination.
https://doi.org/10.1186/s41256-025-00430-0
02
Barriers and Recommendations for Influenza Vaccination Among Healthcare Workers in Chinese Community Health Centers
A study was conducted in 24 urban community health centers and 12 township health centers across four cities in Shandong Province (Jinan, Qingdao, Jining, and Weifang). The results showed that most healthcare workers (86%) were willing to receive the influenza vaccine, yet 32.2% reported that they would not proactively recommend vaccination to others.
Healthcare workers’ vaccination behaviors were influenced by their perceptions of vaccine benefits and risks, confidence in vaccines, and vaccine accessibility. Those who had previously received the influenza vaccine were more likely to recommend it to others.
https://doi.org/10.1080/21645515.2024.2352916
3. School-based Implementation
01
Implementation Strategies to Address Influenza Vaccination Barriers in Beijing Schools
Facilitators for school-based influenza vaccination (SLIV) programs included convenient vaccination channels, intergovernmental collaboration, top-down guidance from authoritative institutions, and integrating SLIV into routine school workflows. Key barriers were parental misconceptions about vaccines, inadequate vaccine supply and coordination of vaccination dates, and lack of planning or information. To address these barriers, the study proposed multi-level strategies at the system, school, and consumer levels, such as developing detailed implementation blueprints, training school personnel, and strengthening engagement with students and parents.
https://doi.org/10.1186/s43058-023-00501-8
02
Survey on Influenza and Influenza Vaccination Knowledge, Infection Status, Uptake, and Influencing Factors Among Primary and Secondary School Teachers in a District of Beijing
In April 2024, a cross-sectional survey was conducted using stratified random sampling, selecting 5 schools each from 51 primary schools and 40 secondary schools in a juridical district. Teachers demonstrated high perceived susceptibility to influenza (e.g., 91.38% considered school outbreaks likely) and perceived severity (e.g., 88.41% believed infection would impact teaching). While 67.59% recognized that influenza vaccination could effectively prevent influenza, awareness of vaccine safety was limited, with 48.00% concerned about potential adverse reactions. Regarding vaccination willingness, physician recommendations (adjusted odds ratio [aOR]=2.62) and provision of free vaccination services for teachers (aOR=10.26) significantly increased their likelihood of getting vaccinated.
https://doi.org/10.3760/cma.j.cn112338-20241224-00821
4. Public and Community
01
CDC Influenza Vaccination Communication Strategy Highlights the Value of Disease Mitigation Messaging
During the 2023–2024 influenza season, the U.S. Centers for Disease Control and Prevention (CDC) conducted targeted influenza vaccination campaigns for pregnant women and parents under the “Wild to Mild” initiative. This strategy emphasized the disease mitigation effect—reducing the severity of illness—to successfully reshape public expectations of influenza vaccine benefits. In the increasingly complex post-pandemic communication environment, evidence-based messaging that highlights the “illness severity reduction” effect, combined with culturally adapted elements, can significantly enhance vaccination willingness among specific populations.
https://doi.org/10.1080/10810730.2025.2453840
02
Characteristics and Determinants of Repeated Influenza Vaccination Among Older Adults in Shanghai, 2020–2022
Although influenza vaccination coverage among older adults in Shanghai remains low, the rate of repeated vaccination has increased. Between 2020 and 2022, the average vaccination coverage among registered older adults was 4.1%, showing a declining trend. However, the rate of repeated vaccination rose from 28.35% in 2020 to 63.53% in 2021 and 64.38% in 2022. Factors promoting repeated vaccination included good management through community health centers, Shanghai residential household registration, and advanced age (70 years and above). The study also indicated that repeated influenza vaccination did not increase the risk of adverse events.
https://doi.org/10.1080/21645515.2024.2364480
03
Effectiveness of Instant Messaging Intervention on Influenza Vaccination Among Older Adults in China: From Willingness to Action
This study was conducted in Shandong among older adults with initially low influenza vaccination willingness. An ecological momentary intervention (EMI) was implemented by showing a 2-minute influenza awareness video jointly produced by the Chinese CDC and the World Health Organization, covering basic influenza information and the importance of vaccination. After viewing the video, participants’ willingness to vaccinate was reassessed via questionnaire. Following the EMI, the proportion of older adults willing to receive the influenza vaccine increased to 79.8% (95% CI: 78.4%–81.2%), an increase of 18.5% (95% CI: 16.3%–20.7%). Correspondingly, the actual influenza vaccination rate rose from 40.4% (95% CI: 38.5%–42.3%) before the intervention to 53.9%, an increase of 13.5% (95% CI: 10.9%–16.2%).
https://doi.org/10.1016/j.vaccine.2024.05.032
04
Strengthening Vaccination Through Community Engagement: Evidence from China
This study analyzed data from the 2021 China General Social Survey (CGSS) and found that individuals who received community notifications were more likely to have COVID-19 vaccine up-take compared with those who did not receive notifications (100% vs. 53.3%). Influenza vaccination rates were also significantly higher among the notified group (2.7% vs. 1.9%). Mechanism analysis indicated that community notifications increased vaccination uptake by enhancing individuals’ awareness of vaccine benefits. Heterogeneity analysis further revealed that the impact of community engagement was particularly pronounced among older adults, individuals with lower educational attainment, and those with poorer economic conditions.
https://doi.org/10.1038/s41598-024-61583-5
05
Differences in Influenza Vaccination Hesitancy and Decision-Making Between Parents and Grandparent Caregivers of Preschool Children: A Comparative Study
Grandparents demonstrated more positive attitudes and higher willingness toward influenza vaccination for themselves and their grandchildren. Using a self-developed Influenza Vaccination Hesitancy (IVH) scale and a vaccine hesitancy determinants matrix, the study analyzed key factors influencing vaccination attitudes and decisions in both groups. The IVH score for parents was 32 (IQR: 28–36), significantly higher than that of grandparents at 30 (IQR: 25–33) (p < 0.001), indicating that grandparents held more favorable views toward influenza vaccination. Mandatory vaccination policies positively influenced the vaccination attitudes of both groups, and adequate vaccine supply was identified as a key facilitator for both parents and grandparents.
https://doi.org/10.1016/j.vaccine.2025.127696
5. Demand Forecasting and Surveillance
01
Optimizing Influenza Vaccine Allocation: A Public Health Planning–Based Demand Forecasting Approach
The study retrospectively analyzed influenza vaccination data from multiple Mayo Clinic regions over four past flu seasons, including electronic health records, employee occupational health files, and inventory records. Analysis showed that approximately 68% of quadrivalent influenza vaccines and 85% of high-dose vaccines were administered between August and November each year. Based on this temporal pattern, the team developed a forecasting algorithm focusing on two key parameters: the early-season vaccination proportion (August–November) and a demand adjustment factor for the remaining quarters. Comparing actual data from the 2023–2024 flu season with model predictions demonstrated the algorithm’s strong performance. For Regions 3 and 5, the error rate between ordered and administered quadrivalent vaccines was below 10%. Compared with traditional allocation methods, the new strategy saved over USD 1 million while minimizing the risk of vaccine shortages.
https://doi.org/10.1093/ajhp/zxae336
02
International Comparative Study on Seasonal Influenza Vaccine Demand Planning and Implications for the German System
Germany faces multiple challenges in influenza vaccine supply, including unreliable demand forecasting, complex administrative procedures, non-binding orders, excessive financial risk for healthcare providers, significant vaccine wastage, and an underdeveloped replenishment system. The study suggests that Germany could optimize its influenza vaccine demand planning by drawing lessons from other countries: Australia implements cross-state vaccine demand forecasting and a strict vaccine registration system; Canada coordinates vaccine distribution through federal–provincial bulk procurement and effectively utilizes surplus stock; the UK employs the ImmForm online platform for centralized ordering and real-time monitoring; the US encourages pre-order systems to reduce supply chain delays; Switzerland has established an emergency vaccine redistribution mechanism; and Singapore optimizes vaccine allocation through public–private partnerships.
International experience: https://doi.org/10.1186/s12889-025-22420-0
03
Exploring the Lagged Correlation Between Baidu Search Index and Influenza-Like Illness (ILI): 2014–2019
The study analyzed ILI% data and Baidu Search Index data from 30 provincial-level regions in China between April 2014 and March 2019. Results showed a significant lagged correlation between the overall Baidu index and ILI%, with a median lag of 0.5 days. The prevention and symptom indices responded more quickly to ILI%, with median lags of -9 and -0.5 days, respectively, while the general and treatment indices had median lags of 0 and 3 days. These findings suggest the potential to develop predictive models based on the prevention and symptom indices to forecast influenza outbreaks and provide early warning.
https://weekly.chinacdc.cn/en/article/doi/10.46234/ccdcw2024.084
Content Editor: Tianyi Deng
Page Editor: Ruitong Li
