Capacity building in the global polio eradication initiative: individual wins and institutional opportunities, a qualitative analysis.

The Global Polio Eradication Initiative (GPEI) is known to be one of the most successful disease eradication initiatives with massive reductions in polio transmission as well as its contributions to strengthening health systems and capacity building. Existing analyses provide limited insight into how capacity was developed, which forms of capacity were strengthened or neglected, and how these efforts were experienced by implementers. Understanding these factors can be helpful as GPEI accelerates transition and integration into national health systems. This study examines GPEIs capacity-building efforts from the perspectives of GPEI workers across multiple roles, levels and countries. We conducted a qualitative secondary analysis of semi-structured key informant interviews with global, national, and subnational stakeholders involved in GPEI. Data were coded inductively and deductively analyzed through Capacity Building Pyramid by Potter and Brough 2004. Country-based co-authors reviewed findings for contextual accuracy. We found that GPEI substantially strengthened individual and infrastructure capacity through large-scale training of frontline health workers, development of immunization infrastructure, and establishment of operational. Polio-funded platforms enabled outreach to hard-to-reach populations and were leveraged for other health priorities. Despite substantial investments, capacity building has remained largely individual training and program centric. There was insufficient integration into national systems leading to constrained country ownership and, lack of diverse trainings leading to limited supervisory and management capacity. Lessons of capacity building done under GPEI provide important guidance for future planning, and implementation of large-scale interventions. These findings highlight the need to move beyond predominantly individual-focused training toward deliberate, systems-level capacity strengthening. As polio transition planning accelerates, global health policymakers and planners must prioritize systems-level capacity strengthening, sustainable financing, and national governance to ensure continuity of immunization and public health functions beyond GPEI. Leveraging GPEI assets for broader health system strengthening can accelerate progress toward universal immunization and health care.