Enhancing influenza vaccination uptake: a systematic review and meta-analysis of intervention strategies

Despite extensive efforts, global influenza vaccination rates remain suboptimal, particularly among high-risk populations. We conducted a comprehensive literature search up to April 2023. Experimental studies assessing the effectiveness of interventions on influenza vaccination uptake were included, expressed as risk ratios (RR) with 95% confidence intervals (CI). Random-effects meta-analysis models were utilized for pooled estimates, with heterogeneity assessed through I2. Subgroup analyses and meta-regressions were performed. This meta-analysis includes 180 studies involving 2,390,119 participants and comprehensively evaluates the effectiveness of recipient-, provider-, health system-based, and multitarget interventions. Overall, interventions significantly increased vaccination rates, with a pooled RR of 1.26 (95% CI, 1.21 to 1.32). Notably, provider-based interventions were more effective for healthcare workers (RR = 1.56; 95% CI, 1.46 to 1.66), whereas recipient-based interventions were more efficacious for pregnant women (RR = 1.42; 95% CI, 1.09 to 1.85). Multitarget strategies were the most effective among older adults (RR = 2.10; 95% CI, 1.61 to 2.72) and population under age of 18 (RR = 1.53; 95% CI, 1.23 to 1.90). These findings provide critical insights for optimizing public health strategies, underscoring the need for innovative and tailored approaches to enhance global vaccination uptake.