Peer-reviewed article

MULTI-LEVEL DETERMINANTS OF MEASLES AND YELLOW FEVER IMMUNISATION UPTAKE IN NORTH-CENTRAL NIGERIA: A CROSS-SECTIONAL ANALYSIS OF HEALTH SYSTEM DRIVERS

Vincent-Vera Okwosa, Abah Michael Idoko, Adamu Ishaku Akyala, Olutoyin Coker, Ikenna Osemeka Okeke et al. · 30 Jul 2026

Abstract

Despite safe, effective vaccines for measles and yellow fever (YF), North-Central Nigeria continues to experience escalating outbreaks. Vaccine coverage falls below the WHO 80% threshold in key states, yet the multi-level determinants — spanning cold-chain infrastructure, health worker adequacy, stockout rates, and socio-behavioural factors — remain poorly characterised. This study evaluates vaccine coverage levels, identifies infrastructure and system-level determinants of coverage gaps, and examines associations between coverage deficits and disease incidence across three North-Central Nigerian states. We conducted a cross-sectional multi-source secondary data analysis across FCT/Abuja, Nasarawa, and Plateau States using 2020–2024 vaccination coverage records from the NPHCDA DHIS2 database, infrastructure indices from state immunisation supervisory assessments, and confirmed case data from NCDC surveillance. Vaccine coverage for measles (MCV) and YF was compared against the WHO 80% target. Pearson correlation coefficients assessed associations between coverage/infrastructure indicators and disease incidence. Given the three-state analytical unit (n = 3), all correlation p-values are presented as indicative of effect size and direction rather than definitive statistical inferences. A conceptual determinants framework organised findings across three tiers: structural/system, operational, and sociobehavioural. A composite Vaccine Infrastructure and Coverage Score (VICS) was constructed as an exploratory descriptive index to rank state-level immunisation system readiness.Measles vaccine coverage ranged from 74% (Nasarawa) to 88% (FCT/Abuja); YF coverage from 69% (Nasarawa) to 84% (FCT/Abuja). No state achieved the WHO 80% YF target; only FCT/Abuja met the measles target. Coldchain functionality was 71% in Nasarawa and 76% in Plateau, versus 92% in FCT/Abuja. Vaccine stockout rates were highest in Nasarawa (39%) and Plateau (33%). Strong inverse associations were observed between measles coverage and measles incidence (r = −1.000; p = 0.017) and between YF coverage and YF incidence (r = −0.993; p = 0.073). Stockout rate was positively associated with measles incidence (r = 0.999; p = 0.033). Nasarawa recorded the lowest composite VICS (64.2/100), consistent with its highest dual-disease incidence burden. Vaccine coverage gaps in North-Central Nigeria are primarily associated with cold-chain infrastructure failures, high stockout rates, and health worker inadequacy rather than socio-behavioural barriers alone. Nasarawa State is the priority intervention target. Urgent coordinated investments in cold-chain rehabilitation, zero-dose child identification through DHIS2 microplanning, and integrated measles–YF SIAs are recommended. KEYWORDS: measles vaccine coverage; yellow fever vaccine coverage; cold-chain; stockout; health worker adequacy; Nigeria; immunisation determinants; NPHCDA; DHIS2; vaccine-preventable diseases