Title : Strengthening global vaccination efforts in fragile settings requires aligning vaccine product design with field realities
Abstract:
Background: In fragile and displacement settings, vaccine delivery continuity is often constrained by product characteristics rather than clinical efficacy. Vaccines designed for stable cold chains, skilled personnel, and multi-dose regimens may underperform when populations are mobile, leading to reduced series completion, increased cold chain excursions, and operational errors.
Methods: Drawing on field evidence from the Democratic Republic of Congo, South Sudan, Liberia, and Nigeria, this study presents the Field-Anchored Vaccine Specification Matrix (FAVSM), a structured framework that synthesizes operational experience and programmatic evidence to translate field constraints into product design requirements across four fragility domains: conflict, displacement, rural-remote, and urban informal settlements. The framework is published as a peer-reviewed book chapter in Vaccine Development: Lessons Learned and Future Trends (IntechOpen, 2026).
Results: The FAVSM identifies vaccine series completion as a key proxy for continuity of care and demonstrates that product attributes such as single-dose presentation, elimination of reconstitution steps, and thermostability are critical determinants of performance. Domain- specific weighting further shows that ease of administration can outweigh extended shelf-life in high-pressure delivery contexts.
Conclusions: Ensuring vaccine continuity for populations in motion requires aligning product design with field realities. The FAVSM provides a practical, evidence-informed framework to guide research and development toward vaccines that are not only efficacious but operationally fit for fragile settings.
