Identifying characteristics that enable resilient immunization programs: a scoping review

Abstract

Abstract Objectives The COVID-19 pandemic highlighted the fragility of immunization programs and resulted in a significant reduction in vaccination rates, with increasing vaccine preventable disease outbreaks consequently reported. These vulnerabilities underscore the importance of resilient immunization programs to ensure optimal performance during crises. To date, a framework for assessing immunization program resilience does not exist. We conducted a scoping review of immunization programs during times of crises to identify factors that characterize resilient immunization programs, which may inform an Immunization Program Resilience Tool. Design Scoping review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews (PRISMA-ScR) guidelines. Data Sources CINAHL, CENTRAL, Embase, Google Scholar, MEDLINE, PsycINFO and Web of Science, databases were searched between 01-Jan-2011 to 02-Sep-2023. Citation searching of identified studies was also performed. Eligibility Criteria We included primary empirical peer-reviewed studies that discussed the resilience of immunization program to crises, shocks, or disruptions. Data extraction and synthesis Two independent reviewers screened records and performed data extraction. We extracted data on study location and design, crisis description, and resilience characteristics discussed, and identified evidence gaps in the literature. Findings were synthesized using tabulation and an evidence gap map. Results Thirty-seven studies met eligibility criteria. These studies captured research conducted across six continents, with most concentrated in Africa, Asia, and Europe. One study had a Randomized controlled trial (RCT) design, while 36 studies had observational designs (15 analytical and 21 descriptive). We identified five characteristics of resilient immunization programs drawing on the Health System Resilience Index (Integration, Awareness, Resource Availability and Access, Adaptiveness, and Self-regulation) and several evidence gaps in the literature. Conclusions To our knowledge, no immunization program resilience tool exists. We identified factors from the Health System Resilience Index coupled with factors identified through primary empirical evidence, which may inform development of an immunization program resilience tool.