High-Resolution Geospatial Mapping of Zero-Dose and Underimmunized Children Following Nigeria's 2021 Multiple...

Area of Science:

• Public Health
• Epidemiology
• Geospatial Analysis

Background:

• Nigeria has the world's largest population of "zero-dose" children, defined as those lacking any routine vaccinations or the initial diphtheria, tetanus, and pertussis vaccine.
• Over 2.3 million unvaccinated children were estimated in Nigeria as of 2022, highlighting a critical public health challenge.

Purpose of the Study:

• To identify and map "zero-dose" and underimmunized children in Nigeria.
• To pinpoint high-risk geographical areas for targeted immunization interventions.

Main Methods:

• Utilized data from the 2021 Nigeria Multiple Indicator Cluster Survey/National Immunization Coverage Survey.
• Employed high-resolution (1 × 1 km) geospatial modeling to predict the prevalence and distribution of unvaccinated children.

Main Results:

• "Zero-dose" and underimmunized children are disproportionately found in socially deprived populations.
• Positive correlations were observed between unvaccinated children and factors including stunting, contraceptive prevalence, and literacy.
• Significant regional and ethnic variations in prevalence were noted, with higher rates in northern Nigeria, indicating substantial heterogeneity.

Conclusions:

• Enhancing Nigeria's immunization system is crucial for improving vaccine coverage.
• Geospatial modeling offers an effective strategy for delivering vaccines to underserved communities.
• Equitable vaccine access is essential for achieving global vaccination goals.