Abstract:

Despite over 1.9 million mpox vaccine doses being formally allocated to African countries by 2025, Africa CDC data indicate utilization rates of approximately 63% for MVA-BN and 25% for LC16m8 vaccines, representing a substantial allocation-to-administration gap. This paper examines structural, regulatory, health-system, and socio-behavioural determinants of vaccination continuum gaps in Africa’s mpox response. A systematic review and mixed-methods synthesis of 120 studies (2016–2026) was conducted following PRISMA 2020 guidelines. A random-effects meta-analysis (DerSimonian–Laird) pooled utilization rates across nine eligible studies. Determinants were synthesised narratively using the WHO Health Systems Framework and Consolidated Framework for Implementation Research (CFIR). Cross-country disparities were analysed by setting type and regulatory readiness tier. The pooled vaccine utilization rate was 0.76 (95% CI: 0.71–0.81; I² = 81%), indicating a mean utilization gap of approximately 24%. Utilization ranged from 82–90% in stable urban settings to 55–70% in conflict-affected contexts. Regulatory readiness strongly moderated outcomes: countries with high readiness achieved pooled uptake of 66% compared to 46% in low-readiness settings. An integrated cascade model emerged: structural constraints drive the allocation gap; governance and health-system readiness determine the administration gap; and socio-behavioural factors shape the uptake gap. Three country readiness tiers were identified with distinct gap profiles. Closing Africa’s mpox vaccination gap requires simultaneous interventions across all continuum stages. Evidence-based recommendations include risk-based allocation algorithms, regulatory harmonisation through AVAREF and AMA, cold-chain investment, workforce surge capacity, and community trust-building. Governance and system readiness are the critical mediators of vaccination performance.

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