Zero-dose vaccination in West and Central Africa after the COVID-19 disruption: trends, subregional inequalities and recovery, 2019-2024

Abstract Background Immunization Agenda 2030 (IA2030) aims to halve the number of zero-dose children from the 2019 baseline, but progress across West and Central Africa is uneven. We compared post-pandemic trajectories, recovery to pre-COVID-19 levels and between-country inequality in initial access to routine immunization across the two subregions. Methods We conducted a secondary ecological analysis of the WHO/UNICEF Estimates of National Immunization Coverage (WUENIC), using the 2025 revision for 25 countries in geographic Western Africa (n = 16) and Middle Africa/Central Africa (n = 9). Zero-dose prevalence was defined as 100 minus DTP1 coverage. We summarized annual distributions from 2019 to 2024 using medians, interquartile ranges, means, coefficients of variation and unweighted Gini coefficients. Recovery, country-rank persistence and subregional differences were also examined. Results Across all 25 countries, median zero-dose prevalence increased from 14.0% in 2019 to 19.0% in 2021 and declined to 13.0% in 2024. The 2024 median remained substantially higher in Central Africa than in West Africa (18.0% vs 8.5%; Mann–Whitney U = 26, p = 0.010). Six countries had zero-dose prevalence ≥ 20% in 2024—four in Central Africa and two in West Africa—whereas all six countries at ≤ 5% were in West Africa. The pooled Gini coefficient was 0.394 in 2019, peaked at 0.411 in 2022 and was 0.386 in 2024. From 2019 to 2024, 12 countries improved, three were unchanged and 10 worsened; 15 of 25 had returned to or exceeded their 2019 DTP1 level. Country rankings remained strongly persistent (Spearman rho = 0.711; p < 0.001), while the paired 2019–2024 distribution showed no uniform shift (Wilcoxon p = 0.625). Conclusions Regional recovery masks a durable subregional divide. West Africa experienced a pandemic-era setback followed by partial recovery, whereas Central Africa entered the period with much larger access gaps and still had more than twice the median zero-dose prevalence of West Africa in 2024. IA2030 acceleration should combine protection of gains in higher-performing programmes with concentrated, subnationally targeted primary-health-care and immunization investments in persistent high-burden settings.