Tanzania’s immunization program, aligned with national strategies, emphasizes universal, quality, and gender-sensitive services.1 Although Tanzania’s vaccination coverage has been historically high, the country experienced declines during the COVID-19 pandemic which have persisted, despite efforts from the Ministry of Health (MOH). The 2024 WUENIC data reported 87% coverage for the first dose of Pentavalent vaccine, dropping to 83% of the third dose.2 According to national estimates, around 7% of Tanzania’s children are classified as zero-dose (ZD), residing in predominantly underserved communities.

To improve immunization service delivery and reduce the percentage of ZD and under-immunized children, Tanzania’s MOH began investing efforts in the immunization service experience (SE). Service experience encompasses all aspects of client interaction with health services, from accessibility, convenience, and quality of care to client satisfaction and outcomes. In the context of immunization, it spans the entire process from the client’s initial awareness and engagement with immunization services to delivery of care and follow-up care. It includes health worker behavior, service delivery efficiency, and the environment in which immunizations are administered. Understanding SE is crucial for improving the ability of health workers to provide high-quality services and the systems and environments they need to do so. It is also critical for improving demand for and uptake of services, client satisfaction, adherence to vaccination schedules, and public health outcomes.

In 2025, the MOH tested a newly developed global guideline, “Enhancing the Immunization Service Experience: A Practical Guide for Immunization Managers”3. The guideline provides district-level management with a framework for how to implement and monitor select evidence-based interventions to improve immunization service experience. The Tanzanian MOH agreed to pilot test the guide and interventions, documenting lessons learned to improve the guide and its use. This case study reports lessons of this pilot and guides a path toward wider use.