This final ZDLH semiannual update (October 2025) highlights the consortium’s efforts to generate and use evidence, deepening the understanding of factors that influence the implementation and effectiveness of strategies for reaching zero-dose and under-immunized children, and missed communities. Explore the data dashboards and visit Related Resources to download each country's final semiannual update narrative.

The April 2025 semiannual update for the Gavi Board and other stakeholders highlights the ZDLH consortium’s efforts to generate and share evidence for a deeper understanding of the factors that affect the implementation and performance of strategies to identify and reach zero-dose and under-immunized children and missed communities. It synthesizes findings, challenges, and recommendations across the IRMMA Framework emerging from the Learning Hubs.

The October 2024 semiannual update for the Gavi Board and other stakeholders highlights the ZDLH consortium’s efforts to generate and share evidence for a deeper understanding of the factors that affect the implementation and performance of strategies to identify and reach zero-dose and under-immunized children, and missed communities. It synthesizes findings, challenges, and recommendations across the IRMMA framework emerging from the Learning Hubs.

The ZDLH helps generate, synthesize, and share ZD data and evidence at both the global and country levels. The structure is a hub-and-spoke model: JSI, the global learning partner manages learning and evidence at the global level, and four country learning hubs in Bangladesh, Mali, Nigeria, and Uganda, comprised of local partners/consortiums, capture and use country-level programmatic data and evidence to provide insights on how the ZD strategy is being translated at the subnational level through improved monitoring and evidence generation. This semiannual update synthesizes findings, challenges, and recommendations across the IRMMA framework emerging from the Learning Hubs.

This October 2023 ZDLH semiannual update informs Gavi, the Vaccine Alliance 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 zero-dose and under-immunized children, and missed communities.