BACKGROUND:
Measles remains one of the leading causes of vaccine-preventable child deaths, particularly in low- and middle-income countries (LMICs) where fragile health systems and inequities hinder vaccine delivery. Despite decades of global efforts, coverage remains below elimination thresholds. Using the 2024 WHO/UNICEF Estimates of National Immunization Coverage (WUENIC), this study assessed global measles coverage trends, disparities, and progress toward Immunization Agenda 2030 (IA2030) targets.

METHODS:
Data for 137 LMICs (2019–2024) were analysed using descriptive statistics, Welch’s t-tests, and Wilcoxon rank-sum tests to compare fragile and non-fragile states. Inequality was quantified using Gini coefficients, while k-means clustering (k = 4) grouped countries by coverage, dropout, unvaccinated counts, and fragility share. Bounded linear models projected first-dose coverage (MCV1) to 2030.

RESULTS:
In 2024, mean MCV1 coverage was 79.2% (95% CI: 76.8–81.6), with fragile LMICs averaging 68.5% compared to 87.4% in non-fragile LMICs (difference = −18.1 percentage points; p < 0.001). MCV2 gaps were larger (−26.9 points; p < 0.001). An estimated 15.6 million children remained unvaccinated for MCV1 and 22.4 million for MCV2, with West and Central Africa accounting for 46.2% of MCV1-unvaccinated children. Inter-country inequality increased (Gini 0.22→0.25). Clustering identified four country profiles requiring differentiated approaches: (1) very low coverage + high fragility, (2) high coverage + low dropout, (3) severe dropout, and (4) moderate dropout.

CONCLUSIONS:
Persistent and widening measles immunisation gaps—especially in fragile settings—threaten IA2030’s 90% coverage goal. Combining WUENIC’s 2024 revision with fragility-sensitive clustering provides a practical framework to target equity-focused strategies, prioritising fragile and high-burden countries for intensified support and adaptive delivery approaches.