Lessons Learned from routine immunization strengthening program in South Sudan

South Sudan’s Greater Upper Nile region is a complex environment with significant operational challenges to delivering vaccines while navigating seasonal floodings, insecurity and conflict, and cold chain constraints. The Gates Foundation has supported routine immunization strengthening in the Greater Upper Nile region of South Sudan from 2018 to 2025, implemented by Access For Humanity (AFH).

To better understand implementation successes, adaptation, and emerging lessons, the foundation commissioned Development Delivery Partners (DDP) to document the program experience in 2024 - 2025. The materials provide detailed insight into how teams are navigating these constraints, including the role of mobile outreach as a primary delivery mechanism; the importance of community systems in identifying and following up missed children; and the operational realities of maintaining cold chain functionality down to the last mile.

The lessons learned, for the use of program managers, implementers, donors operating in similar complex settings, are provided as:

• Short documentary videos
• Case reports
• Two-page case summaries

Documentary videos 

Case reports: Full narrative reports 

Case summaries: Two-page summary of key insights