This semiannual update for the Gavi Board and other stakeholders highlights the ZDLH consortium’s efforts to leverage evidence for a deeper understanding of the factors that affect the implementation and performance of strategies to identify and reach ZD and under-immunized (UI) children and missed communities. It synthesizes findings, challenges, and recommendations across the IRMMA framework emerging from the Learning Hubs. See the country reports for a detailed summary of each country’s priorities, activities, progress, and learnings to date.

This ZDLH semiannual update informs Gavi, the Vaccine Alliance Board (Gavi Board) and other stakeholders about the mechanism’s work to use evidence to better understand the factors influencing implementation and performance of approaches to identify and reach ZD and under-immunized (UI) children and missed communities.