Design, Development, and Deployment of an Electronic Immunization Registry: Experiences From Vietnam, Tanzania, and Zambia

"...aim to provide practical, operational insights to country decision-makers and partners who are considering or are in the process of implementing an EIR."

In many low- and middle-income countries (LMICs), immunisation information has traditionally been captured through paper-based tools at health facilities. However, as many LMICs are undergoing digital transformation of their health systems, there is an opportunity to leverage digital health solutions for immunisation. One such tool is an electronic immunisation registry (EIR), a confidential, computerised, population-based routine system to capture, store, access, and share individual-level, longitudinal health information on vaccine doses administered. A 2021 report found that EIRs had been piloted or implemented in more than 50 LMICs. This paper documents the practical experience of scaling an EIR across 3 country contexts: Vietnam, Tanzania, and Zambia.

Vietnam, Tanzania, and Zambia began designing and developing EIRs in the 2010s; each country is in the process of scaling an EIR nationwide. PATH, an international non-governmental organization (NGO) whose mission is to advance health equity, has been collaborating with and providing technical support to these country governments to introduce and scale their EIRs. Each country immunisation context is described in Table 1 of the paper; key characteristics of each country's EIR are outlined in Table 2. In short:

• Vietnam: ImmReg, a digital registry to manage individual vaccination history, and VaxTrak, a digital vaccine stock management tool, grew from a district-level pilot to a central piece of the country's health system, as part of the National Immunization Information System (NIIS) launched nationwide in 2017. As of October 2022, the NIIS includes 32.2 million client records and has been implemented in 16,000 facilities. In the second half of 2020, the government of Vietnam began transitioning to a paperless immunisation system.
• Tanzania: Tanzania's Ministry of Health, Community Development, Gender, Elderly and Children and PATH collaborated to design and implement an EIR. The first iteration, the Tanzania Immunization Information System, was developed in 2014, but due to technical challenges was replaced by a new system - the Tanzania Immunization Registry (TImR) - in 2016. From 2018 to 2019, the Tanga region transitioned to completely paperless reporting; Mwanza and Kilimanjaro regions transitioned to paperless reporting in April 2021. As of April 2021, TImR includes 1.9 million client records and has been implemented in 3,736 of approximately 6,000 facilities across 15 of 26 regions in mainland Tanzania.
• Zambia: Beginning in 2015, the Zambia Ministry of Health (MOH) partnered with PATH to develop an EIR. In early 2017, Zambia turned to the Open Smart Register Platform (OpenSRP) to develop the Zambia Electronic Immunization Registry (ZEIR). As of October 2022, ZEIR has been implemented in 29 districts in Southern and Western Provinces, capturing more than 329,000 client records across 596 health facilities.

Although each country's implementation experience has been well documented (see, e.g., Related Summaries, below), the present paper compares experiences related to 4 factors:

1. Timelines: The cases highlight the long timeline required to implement an EIR at scale. In Vietnam, it took 7 years from the start of Project Optimize to the nationwide introduction of the NIIS. In Tanzania and Zambia, 9 years after the EIR development process began, both countries are still in the process of scaling the EIR nationwide. Across all 3 countries, the timeline included multiple system iterations.
2. Partnerships: In all 3 case countries, interdisciplinary teams were established to oversee the EIR projects. At the national level, all cases highlight the importance of MOH leadership through all EIR phases to ensure country ownership, sustainability, and alignment with national strategies and standards. At subnational levels, all cases highlight the importance of user-centred design to inform the EIR design and development.
3. Financial costs: EIR guidance documents emphasise the need to develop a funding model that can sustain the project through the entire process.
4. Technology and infrastructure: All 3 case countries underscore the need to understand the local technology and infrastructure context and design the EIR to fit the context. An important aspect of ongoing technical support is direct support to end users.

The researchers note that, for new countries implementing EIRs, the design and development phases should be streamlined compared to these 3 case countries because the technology has advanced. In Vietnam, Tanzania, and Zambia, the importance of planning for sustainability and scale from the start was an emergent cross-cutting theme. Partnerships that promote government ownership and engage end users can foster sustainability. The importance of planning for ongoing financing, technical support, and system maintenance at scale was also highlighted.

Recommendations include:

• Plan for an iterative EIR development process to strengthen the system over the long term.
• Include end users from the start to inform the system requirements, support pilot testing, and provide routine feedback to inform incremental system updates.
• Establish an interdisciplinary team to oversee the EIR design, development, and deployment; national government/MOH staff should lead to ensure country ownership, sustainability, and alignment with national strategies and standards.
• Formalise team roles, responsibilities, and commitments of this interdisciplinary team through a written agreement.
• Ensure funding to sustain and maintain the EIR system.
• Capture costs on EIR design, development, and deployment to fill existing evidence gaps and test the hypothesis that there are economies of scale and cost savings from adapting existing systems.
• Develop long-term plans for ongoing system maintenance, updates, and end-user support. This should include identifying local expertise to provide ongoing system maintenance and support.
• Consider sustainability and scale from the beginning by establishing government ownership; planning for long-term financing, system maintenance, and user support; and preparing for the transition from the legacy tools to new tools.

"The findings and recommendations from this study can inform other countries considering or in the process of implementing an EIR."