Demand Side Incentives Project (DSI)

Background Immunisation coverage is a critical aspect of public health, as it protects children from vaccine-preventable diseases and deaths. However, according to World Health Organisations and United Nations Children's Education Fund, WHO/UNICEF Estimates of National Immunisation Coverage (WUENIC) data, approximately 25 million children worldwide missed out on life-saving vaccines in 2021, an increase of 6 million compared to 2019. This included 18.2 million zero-dose children, with more than 60% of them living in ten countries, including Nigeria. The global coverage of the third dose of diphtheria-tetanus-pertussis (DTP3) also declined from 86% in 2019 to 81% in 2021 according to the same WUENIC reports, the lowest level since 2008. Several factors have been identified as potentially contributing to this decline, such as increased conflict and fragile settings, misinformation, and disruptions caused by the Corona Virus Disease 2019 (COVID-19) pandemic, including service and supply chain disruptions and resource diversion to pandemic response efforts. The 2022 WUENIC results however show that vaccination coverage has started to improve following on from the decline in the preceding years.

Each year, nearly 2.5 million children living in Nigeria do not receive DTP1, and in 2020, an additional 500,000 children were unvaccinated because of the COVID-19 pandemic. In Nigeria, DTP1 coverage was reported in the 2022 Multiple Indicator Cluster Survey (MICS) to be 68%. The 2021 WHO/UNICEF estimates of national immunisation coverage (WUENIC) report a DTP1 coverage of 70%. Data from the District Health Information System 2 (DHIS 2) for 2022 shows cumulative DTP1 national coverage at 90.95%. These differences in coverage contribute to the challenges of visibility into where and why zero dose children exist.

The Equity Reference Group for Immunisation (ERG) has emphasised and called for a greater focus on four key areas to reach Zero dose children, namely conflict-affected, urban poor, and remote rural areas as well as gender-related barriers. Factors that have been reported to drive the existence of zero dose children in Nigeria include maternal education, fears and misconceptions, and access to health facilities, many of which are intricately linked to the four key areas identified by the ERG. Approximately 55% of zero-dose children in Nigeria however are concentrated in seven states - Kano, Sokoto, Bauchi, Katsina, Niger, Zamfara and Kaduna and are at greater risk of becoming sick or dying from preventable diseases. Sub-national variations in coverage exist, with Lagos and Kano states contributing the largest burden of zero-dose children despite significant differences between the state level coverages.

Inequities in immunisation coverage are reportedly common in urban areas affecting the urban poor, who often live in urban slums. Cumulative DTP1 coverages higher than 100% are unfortunately not uncommon on the DHIS 2, appearing to be reported more often among urban LGAs than among rural LGAs. In-country stakeholders largely attribute this data quality issue to the denominator used to calculate the coverage, as this denominator is based on the projected growth rates from the 2006 population census. The factors around geographical location however run deeper than the level of the LGA with administrative data on the DHIS 2 also showing disparities in DTP1 coverage between health facilities. Nigeria also has communities that have or are still experiencing conflicts, contributing to limited access to immunisation services in these communities and increased number of zero-dose children.

To improve immunisation coverage, Nigeria adopted the Reach Every Ward (REW) strategy in 2005, the REW strategy focuses on routine immunisation in health facilities and outreaches, including components such as improved access for under-served and hard-to-reach areas; supportive supervision; monitoring and use of data for action; community mobilisation and improving community links with service delivery. The National Emergency RI Coordination Centre (NERICC) implements the Optimised Integrated Routine Immunisation Sessions (OIRIS) approach with five key pillars: optimised Routine Immunisation (RI) sessions, integration with other services, intensified supportive supervision, ownership, and accountability. OIRIS aims to enhance RI service access by removing barriers through improved microplan development and implementation in states and Local Government Areas (LGAs). OIRIS also drives the implementation of the revised community engagement strategy, with community level line-listing of newborns to support connection to immunisation services, as a complement to other communications and demand generation activities and strategies.