Interventions Addressing Vaccine Hesitancy in the WHO European Region and in North America (United States and Canada): A Systematic Review

Objective: Vaccine hesitancy threatens optimal immunization coverage. This review systematically identified and evaluated interventions addressing vaccine hesitancy in the WHO European Region and in North America (United States and Canada).Methods: A systematic search was conducted across PubMed, Scopus, PsycInfo, Cochrane Library, and Embase from inception to 17 January 2024. Eligible studies evaluated interventions targeting vaccine hesitancy. Data extraction and risk-of-bias assessment followed the methodological guidance of the Cochrane Handbook, and reporting adhered to PRISMA 2020 guidelines. The review protocol was registered in PROSPERO (CRD42024565588). Interventions were categorized as educational, communicational, policy-based, organizational, or digital.Results: A total of 59 studies met the inclusion criteria. Effective approaches included multicomponent strategies, community engagement, reminder and recall systems, educational campaigns, and legislative measures. Digital interventions yielded promising but heterogeneous results. The effectiveness of interventions was often enhanced when tailored to specific population needs and local contexts.Conclusion: Multifaceted interventions adapted to the sociocultural context appear most effective in reducing vaccine hesitancy in Europe and North America. Further high-quality studies are needed to refine implementation strategies and evaluate long-term impacts.