Recovering Lost Gains in Routine Childhood Immunization

The Sabin Vaccine Institute’s Vaccine Acceptance & Demand initiative is proud to provide funding to 7 grant partners awarded through the 2023-2024 Social and Behavioral Research Grants Program. This blog is the first in a series examining the selected research projects based on one of three themes: zero-dose children, life-course immunization, and operationalizing of the WHO BeSD Framework.

Data from the World Health Organization (WHO) and UNICEF indicates that the COVID-19 pandemic has contributed to the greatest global decline in childhood vaccinations in 30 years, with 25 million children missing out on vaccinations in 2021 alone. According to the UNICEF State of the World’s Children 2023 Report, this is a 31% increase in the number of children missing vaccinations from 2019 and contributes to the estimated 67 million children missing out on routine immunization between 2019 and 2021. These data also demonstrate an increase in zero-dose children, defined by Gavi as children who have not received a single dose of diphtheria, tetanus and pertussis (DTP)-containing vaccine. Vaccine coverage dropped in every region, but the most severe impacts were felt across low-and middle-income countries (LMICs). Such a rapid and sharp decline rolls back decades-long advancements in global immunization while hindering the attainment of present goals.

These three Sabin-funded projects are focusing on ways to restore childhood immunizations back to pre-pandemic levels. In alignment with the goals outlined in the Immunization Agenda (IA 2030) to reach 90% coverage of essential vaccines by the year 2030, grant partner teams are prioritizing under-served and marginalized populations, including children with disabilities and families living in urban slums, zero-dose children are a key subset of these populations.

Many of the social and structural determinants of health including economic stability, gender, physical environment, education, food security, social context, and health care system may contribute to missed immunizations. Half of all zero-dose children are predominantly found within densely populated urban, remote/hard-to-reach, or fragile and/or conflict-settings, and two-thirds live in just five countries: Nigeria, India, the Democratic Republic of the Congo, Pakistan, and Ethiopia. All teams funded in this track are situated in countries with the highest number of ZDC (Nigeria, Ethiopia, Pakistan), undertaking mixed methods studies to investigate various social and structural determinants of ZDC in their communities.

Sabin Vaccine Institute is proud to support the following 2023-2024 Social and Behavioral Research Grant partners in their pursuit of solutions to lost gains in routine immunizations due to the COVID-19 pandemic. These projects conduct research in both rural and urban slum populations within Nigeria, Pakistan, and Ethiopia to assess the prevalence of zero-dose children, understand the structural determinants of zero-dose populations, and implement and evaluate solutions to improve vaccination uptake amongst zero-dose children within these settings. The knowledge gained from these projects will have a variety of uses, including informing immunization-related policy and programming, including further understanding of both demand-side and supply-side barriers, intervention cost-effectiveness, and provision of immunization cascade data.

Meet Our Partner Teams Focused on Zero-dose Children

Design-thinking for Improving Immunization Micro-planning Processes in Zero-dose Communities (Di-Micro Plan) in Nigeria

Dr. Abisoye Oyeyemi, Dr. Titilope Adedeji, and Ganiyat Eshikhena of Corona Management Systems will investigate the structural drivers of zero-dose children in urban slum settlements in Kano State, Nigeria. Kano State has both the highest zero-dose burden and the greatest number of urban slums in Nigeria. Using a design-thinking approach to strengthen the capacity of health workers in developing comprehensive micro-plans focused on reaching children and their families in slum settlements, the team hopes to improve immunization access to zero-dose communities in this setting. The approach is also expected to address knowledge gaps around the structural determinants of zero-dose children in Nigeria alongside assessing the effectiveness of inclusive micro-planning processes on immunization uptake .

 “This research grant will play a crucial role in advancing vaccination policy and programming by supporting research that identifies gaps and barriers in current vaccination efforts, developing new vaccines, testing new vaccination strategies, evaluating vaccination programs, and building capacity. The activities are tailored around estimating the burden of zero dose children and missed communities, assessing the structural determinants and drivers of zero-dose, co-designing and deploying microplanning capacity building among health workers and immunization program managers in urban slums in Kano state. By conducting this research, we believe it will also demonstrate the effectiveness of a design thinking capacity building approach in improving microplanning practices, policymakers and program managers can make evidence-based decisions and implement improvements that can increase vaccination rates and prevent the spread of disease. Summarily, through this research and capacity building activities, this research grant can improve vaccination uptake, prevent the spread of disease, and save lives.”

Understanding Structural Determinants of Zero-dose Children in Urban Slum Communities of Pakistan

This project has been developed by Dr. Omera Naseer, Tanzeel Zohra, and Dr. Aamer Ikram at the National Institutes of Health in Islamabad, Pakistan and explores the socioeconomic and political determinants of zero-dose children living in urban slum communities across three major cities: Karachi, Lahore, and Peshawar. Utilizing a mixed methods approach, the team will also estimate the prevalence of zero-dose children within these urban slum settings. Results from this work will be shared with national, provincial, and local-level decision makers to craft policy and programming solutions to reach zero-dose children with immunization services. This work supports immunization systems as they implement targeted approaches for reaching zero-dose children and ensuring their immunization completion according to WHO recommendations.

“The outcome of this piloted study is expected to integrate clarity in structural determinants of zero-dose children and improve the output of ongoing vaccination campaigns in urban slum communities across Pakistan. Generated data will identify gaps and formulate evidence-based policy and programs that are tailored to the unique needs of these communities and will reduce the liability of zero-dose-associated child mortality in urban slums. In addition, the lessons learned from this research will contribute to and expand the scope of the project to other LMICs with the same socioeconomic and political determinants.”

Assessing the Effect of Active Community-based Surveillance Augmented by Referral Slip in Reducing Zero-dose and Under-immunized Children in Remote and Pastoralist or Semi-Pastoralist Communities in Ethiopia

In partnership with the Consortium of Christian Relief and Development Associations/Core Group Partners Project (CCRDA/CGPP), Negussie Deyessa, Filimona Bisrat, and Legesse Kidanne plan to assess the impact of active community-based surveillance augmented by a referral slip on immunization coverage among zero-dose and under-immunized children living in remote and pastoralist communities in Ethiopia.  Utilizing a cadre of community volunteers (CVs), the team will implement a randomized control trial in 80 pastoralist districts across the country to assess the effectiveness of community-based surveillance along with the use of vaccination referral slips against standard practice in improving uptake of routine immunization among zero-dose children. This project aims to reduce the prevalence of zero-dose children, minimize dropout rates, and improve the timely completion of Ethiopia’s vaccination schedule.

 “This project has devised an intervention to enhance the efficiency of Community Volunteers through referral slips and active community-based surveillance to refer identified newborns, immunization defaulters, and other follow-ups to increase immunization coverage and reduce the number of zero-dose children. The project will use active community-based surveillance augmented by referral slips to help the CVs authenticate the tracking and referring newborns, zero-doze children, and defaulters, including children, in follow-up. Involving CVs in referral slips will strengthen the linkage between CVs and the public to improve demand for immunization, which further helps to enhance performance improvement for herd immunity. The intervention could reduce the high zero dose children, minimize the dropout rate, and improve the timely completion of the vaccination schedule, improving immunization coverage, which will have a high impact on the children by reducing morbidity and mortality from vaccine-preventable diseases. Finally, the study will measure the cost of the intervention using the CVs and compare it against the routine government office level and outreach site vaccination.”

The Sabin Vaccine Institute is a leading advocate for expanding vaccine access and uptake globally, advancing vaccine research and development, and amplifying vaccine knowledge and innovation. Unlocking the potential of vaccines through partnership, Sabin has built a robust ecosystem of funders, innovators, implementers, practitioners, policy makers and public stakeholders to advance its vision of a future free from preventable diseases. As a non-profit with more than two decades of experience, Sabin is committed to finding solutions that last and extending the full benefits of vaccines to all people, regardless of who they are or where they live. At Sabin, we believe in the power of vaccines to change the world.