This article reports a secondary analysis of prospectively collected data from healthcare workers (HCWs) at six hospitals in Georgia to identify factors associated with uptake of seasonal influenza vaccine during three consecutive seasons (2021–2022, 2022–2023, 2023–2024).
The parent study was a longitudinal prospective cohort established in early 2021 to evaluate COVID-19 and influenza vaccine effectiveness among HCWs at six secondary-level urban hospitals in Georgia. Of 3,849 HCWs across the six hospitals, 1,606 (42%) initially enrolled in the cohort. For this secondary analysis the authors restricted to participants who completed all three years of follow-up and who completed the baseline sociodemographic questionnaire, self-reported influenza vaccination status for each of the three seasons, and the Year 3 (early 2023) attitudinal questionnaire. The analytic sample therefore included 403 HCWs.
Questionnaires were administered at enrolment (early 2021) and at re-enrolment in Years 2 and 3 (early 2022 and early 2023). Influenza vaccination status for each season (2021–2022, 2022–2023, 2023–2024) was self-reported by participants. The Year 3 questionnaire included four Likert-scale items on attitudes towards influenza and influenza vaccination and questions about reasons for receiving or not receiving influenza vaccine in the 2022–2023 season. For analysis, attitudinal responses were dichotomized into agreement versus neutral/disagreement or into higher versus lower perceived effectiveness/worry as described in the source. Study data were stored in REDCap.
The primary outcome was influenza vaccination uptake defined as receipt of influenza vaccine in at least one of the three seasons versus receipt in none of the seasons. The authors compared HCWs vaccinated in at least one season with those unvaccinated across all three seasons. Multivariable logistic regression produced adjusted odds ratios (aORs) and 95% confidence intervals (CIs) to identify factors independently associated with uptake. The analysis focused on overall uptake across the three-year period rather than season-specific uptake because restricting to participants with complete follow-up limited sample size and statistical power for seasonal models.
Among the 403 participants the median age was 46 years (interquartile range 36–54) and 364 (90%) were female. Occupational categories were nurses or midwives (168; 42%), support staff (85; 21%), doctors (75; 19%), and other staff (75; 19%). Overall, 289 participants (72%) reported receiving influenza vaccine in at least one of the three seasons, while 114 (28%) reported no influenza vaccination in any season.
In multivariable analysis, age and attitudinal and institutional factors were associated with uptake. HCWs aged 30 years and older were more likely to have been vaccinated across the study period, with the 40–49 age group showing the highest odds of uptake (aOR 2.67, 95% CI 1.09–6.59) compared with younger HCWs.
Beliefs about the safety and effectiveness of the influenza vaccine were strongly associated with uptake. HCWs who did not believe the vaccine was safe had lower odds of vaccination (aOR 0.27, 95% CI 0.11–0.68). Those who doubted vaccine effectiveness were also less likely to be vaccinated (aOR 0.36, 95% CI 0.14–0.89).
No differences in uptake by sex or by occupational category were observed in adjusted models. Notably, participants at one hospital (Hospital B) had substantially lower odds of vaccination (aOR 0.06, 95% CI 0.02–0.23) compared with the reference hospital, indicating marked institutional variation.
The Year 3 questionnaire included items on reasons for vaccination decisions for the 2022–2023 season; the source reports that these responses were collected and categorized for analysis. Specific aggregated reasons were collected as part of the survey and were used to explore motivations and barriers, but the source did not provide detailed enumerated frequencies of each reason in the text excerpt provided here. Details on the distribution of specific reasons are reported in the paper’s supporting information and tables referenced by the authors.
This analysis identifies three key domains associated with influenza vaccine uptake among Georgian HCWs over three seasons: increasing age (particularly age 40–49), confidence in vaccine safety and effectiveness, and facility-level differences. The strong associations between attitudinal measures and uptake align with the broader literature linking vaccine confidence to healthcare worker vaccination behaviour.
Limitations noted by the authors and apparent from the study design include reliance on self-reported vaccination status, restriction to participants with complete three-year follow-up and Year 3 attitudinal data which reduced the analytic sample relative to initial enrolment, and modest sample size that precluded season-specific multivariable analyses. These constraints could affect generalizability and may introduce reporting bias. The source indicates that data and supporting information are available in the published article for further detail.
From a practice perspective, the findings suggest that interventions to increase influenza vaccination among HCWs in Georgia should address concerns about vaccine safety and effectiveness, and consider facility-level barriers or facilitators that produced marked differences between hospitals. Targeted communication for younger HCWs and institution-specific strategies may be warranted.
In this cohort of 403 Georgian HCWs followed across three influenza seasons, 72% received influenza vaccine in at least one season. Lower uptake was associated with doubts about vaccine safety and effectiveness and with attendance at one particular hospital, while older HCWs were more likely to be vaccinated. The authors recommend that future vaccination campaigns for HCWs explicitly address safety and effectiveness concerns and target demographic and institutional disparities to improve uptake. For full methodological details, tables, and supporting data, refer to the published article and its supporting information as cited by the authors.