Reconstruction of immunisation during conflict: A mixed-methods cohort evaluation of programme delivery and outcomes in Myanmar
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Introduction
Routine childhood immunisation is frequently disrupted in conflict-affected settings, leaving many children unvaccinated (zero-dose [ZD]). Their vaccination is now a global priority, but published evidence on restoring immunisation services in these settings is limited. We evaluated a nurse-led, community-based Expanded Programme on Immunisation adapted to a conflict-affected setting in Myanmar, focusing on factors associated with full immunisation (FI) among ZD children.
Methods
This mixed-methods observational cohort study enrolled children from November 2023 to December 2025; analyses of FI outcomes were restricted to children enrolled ≥18 months, with primary analyses focused on ZD children. Associations between programme delivery factors—including vaccination opportunity (the ratio of vaccination sessions available to visits required for FI based on age and vaccination schedule [accelerated versus routine])—and FI were assessed using mixed-effects logistic regression with a random intercept for site. Programme cost and qualitative data from document review and questionnaires were also analysed.
Results
Of 13,263 children enrolled, 6563 (49%) were in the analytic cohort; 2,684 (20%) were ZD. Among ZD, 452 (17%) were FI at 12 months and 1329 (50%) at 18 months. Accelerated schedule (OR 3.00, 95% CI 1.11–8.13) and greater vaccination opportunity (OR 2.1 per 0.5 unit increase in opportunity, 95% CI 1.8–2.4) were strongly associated with FI at 12 months, with smaller effects at 18 months. The cost per fully immunised ZD child was US$147, primarily reflecting substantial vaccine costs. Qualitative findings indicate that community engagement increased demand and access, but insecurity and logistical challenges limited service continuity and vaccination opportunities.
Conclusion
FI improved over time but remained suboptimal through 18 months. Vaccination opportunity and schedule influenced the timing of FI, but sustained follow-up was critical for completion. Community-based delivery enabled restoration of immunisation services where formal systems had collapsed, demonstrating what is possible—and what it demands—in active conflict.
Funding
United Nations
KEY MESSAGES
WHAT IS ALREADY KNOWN ON THIS TOPIC
Reaching zero-dose (ZD) children in fragile and conflict-affected settings is a priority of the WHO Immunization Agenda 2030, but published evidence on programmes attempting to restore immunisation in such settings is limited.
Routine immunisation services in Myanmar collapsed following the 2021 military coup and subsequent access restrictions amounted to a de facto humanitarian blockade.
WHAT THIS STUDY ADDS
This study provides among the first longitudinal evidence on implementation, costs, and outcomes of community-based immunisation among ZD children during active conflict.
Half of ZD children and 78% of those who were incompletely immunised at enrolment achieved full immunisation within 18 months.
Programme factors including accelerated vaccination schedule and increased vaccination opportunities were associated with earlier completion; sustained retention was the dominant determinant of overall coverage.
HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY
Community-based delivery through civil society organisations can restore immunisation services in high priority settings but its fragility and need for sustained external support cannot be ignored.
Expanding vaccination opportunities, using accelerated schedules, and actively retaining children after enrolment are actionable steps to increase coverage.
