Zero-Dose: An Equity Problem

Zero-dose children are believed to be among the world's most vulnerable children, with evidence suggesting that they belong to households and communities suffering from cumulative disadvantage that can be social, political, economic, geographical, and health systems factors reflective of entrenched inequalities.

Routine immunization services are typically the child’s first connection with the health system, and so in addition to providing direct protection, immunization programs provide a unique opportunity to expand the reach of the health system. It has been established that communities where there are clusters of people not receiving vaccination services are also likely not receiving any other essential health services³.  Reaching zero-dose children (and the communities where they reside) can increase their contact with the health system for other types of care as well. Exacerbated by the COVID-19 pandemic, reaching these zero-dose children and missed communities is an even more urgent global priority.

The Immunization Agenda 2030 (IA2030), a new global strategy endorsed by the World Health Assembly in May 2021, aims to reach zero-dose children, and bring them sustainably into the routine immunization system within countries. Aligned to the IA 2030 is the Gavi 5.0 strategy of “leaving no-one behind with immunization” by reaching zero-dose and missed communities. These global strategies recognize that context-specific, country-owned, people-centred, innovative, and tailored approaches must be taken to address this global priority.^4,5

How Can We Contribute to Global Efforts to Reach Every Child?

In working towards reaching every child, innovative approaches, strategic partnerships, transformational leadership, and collaboration across the entire ecosystem is required to ensure that children are reached with life-saving vaccines and health services. Some of our key recommendations include:

• Testing of innovative approaches – The quest to ensure that no child is left behind requires a tailored approach that addresses multiple and intersecting economic vulnerabilities, sociocultural barriers, and health system challenges to deliver immunization services through the primary health care system and WHO’s Expanded Program on Immunization. These innovative approaches need to be designed with, and not just for, the target communities. Principles such as human centered design (HCD), an approach that considers the needs, perspectives, and experiences of end users when designing solutions, should be leveraged for testing and scaling up. Using HCD, we can delve deeper into understanding caregivers/parents of zero-dose, the structural barriers they may face, their motivations, potential enablers to receiving vaccines, etc., in designing solutions to reach them that actually work.
• Strengthening the supply chain: Successful immunization programmes are built on functional, end-to-end supply chain and logistics systems. The goal is to ensure an uninterrupted availability of quality vaccines from manufacturer to service-delivery levels, so that opportunities to vaccinate does not get missed due to non-availability of vaccines. Building strong, resilient, effective, and efficient vaccine supply chains is a crucial step in reducing the number of zero-dose children, as it can improve vaccine distribution, reduce waste, increase uptake, provide real-time data, and reduce costs.
• Supporting national and sub-national planning, budgeting, and training to reach zero-dose children: Targeted country support is required to develop, transfer, and sustain country capacity including human resource capacity to deliver vaccination services. Partners need to work together with global, national, and subnational bodies to review and strengthen country strategies to build the capacity of human resources for immunization, recognizing that human resource capacity is at the heart of diagnosing and resolving the drivers of zero-dose cases and missed communities.
• Supporting immunization policymakers and program managers to generate and disseminate accurate, comprehensive, context-specific, and evidence-based recommendations: This support can take many forms, including providing access to research, data analysis, and technical expertise, as well as building capacity to interpret and use data to inform policy decisions. To be effective, recommendations must be based on robust and comprehensive data, including information on the local context, demographic patterns, and healthcare systems. This information can help policymakers and program makers make informed decisions on how to target resources and allocate funding to where they are needed most. By providing support to immunization policymakers and program managers, we can ensure that the strategies and interventions aimed at reducing the burden of zero-dose children are based on the best available evidence and are well-informed by the local context. This, in turn, can help to increase the impact and effectiveness of these efforts and ultimately, help to ensure that all children have access to life-saving vaccines. A key example of this is the provision of technical support to National Immunization Technical Advisory Groups (NITAGs) as a key aspect of the introduction of new vaccines in countries, as well as reviewing and updating the routine immunization schedule.
• Sharing learnings across and within countries and regions, towards accelerating progress: Evaluating country immunization programs is critical for learning and for accountability, in line with the IA2030 and Gavi 5.0 strategy. This could be through engagements with country governments, donors, multilateral agencies, and national counterparts to evaluate the progress of immunization programs, highlighting learnings and strengthening accountability on the journey to ending zero-doses and missed communities.

IQVIA works with donor organizations and governments to conduct vaccine audits, prioritising the work in Nigeria, which is one of the countries with the world’s highest burden of zero-dose children. IQVIA provides technical support to National Immunization Technical Advisory Groups (NITAGs) and has found this to be critical in the introduction of new vaccines in countries, as well as reviewing and updating the routine immunization schedule.

The challenge of reaching zero dose children and missed communities must not be underestimated. These children represent the most vulnerable communities, and typically, the furthest and hardest communities to reach. IQVIA will continue to contribute to global efforts in promoting the importance of vaccination, in increasing access to life-saving vaccines, and in driving utilization of vaccination of health services among the world’s under-served populations. We continue to push ourselves to do more to advance public health efforts and improve health for all.

¹WHO/UNICEF Immunization Coverage Estimates (WUENIC) 2021

²Cata-Preta, Bianca O., et al. "Zero-dose children and the immunisation cascade: understanding immunisation pathways in low and middle-income countries." Vaccine 39.32 (2021): 4564-4570.

³Wiysonge, Charles S., et al. "Interventions for improving coverage of childhood immunisation in low-and middle-income countries." (2016).

⁴Mahachi, Kurayi, et al. "Zero-or missed-dose children in Nigeria: Contributing factors and interventions to overcome immunization service delivery challenges." Vaccine (2022).

⁵Galles, Natalie C., et al. "Measuring routine childhood vaccination coverage in 204 countries and territories, 1980–2019: a systematic analysis for the Global Burden of Disease Study 2020, Release 1." The Lancet 398.10299 (2021): 503-521.