Mapping the Implementation Determinants and Context of Uganda's National Expanded Program on Immunization: A Scoping Review

Children under 5 years old are among the most vulnerable to vaccine-preventable diseases. This places them at the forefront of immunization efforts, as exemplified in Uganda. Uganda's National Expanded Program on Immunization (UNEPI) has made steady progress in vaccine coverage over the last 4 decades. However, challenges continue to impact the program's implementation. This scoping review identified key determinants, as well as the policies and actors shaping UNEPI's implementation. A total of 76 peer-reviewed and gray literature sources were included. Data were extracted and synthesized using both descriptive and thematic analysis. A total of 60 facilitators and 73 barriers were mapped across nine themes. Prominent facilitators included effective communication and sensitization, strong community mobilization, technical and financial support from implementing partners, and availability of increased funding. Recurring barriers included vaccine stock-outs, shortages, and delays, fear and concern over vaccine side effects, costs associated with vaccination, and negative attitudes and treatment from health workers. Key actors shaping implementation included caregivers, peers and social networks, community leaders and village health teams, health workers, district health teams, government and policymakers, and implementing partners. The key policies shaping UNEPI focus on strengthening community engagement, service delivery, logistics, and governance. The findings from this review demonstrate the need for approaches that strengthen service delivery, logistics, workforce capacity, data use, and meaningful community engagement together.