Mpox vaccination uptake and acceptance in the Democratic Republic of Congo: a systematic review and meta-analysis

The Democratic Republic of Congo (DRC) is recognized as the global epicenter of human Mpox. While vaccination is crucial for outbreak prevention, especially as the disease transitions from zoonotic spillover to sustained human-to-human transmission, comprehensive assessments of vaccination coverage trends across the country are notably absent from the literature. This systematic review and meta-analysis address this gap by providing the first pooled estimate of Mpox vaccine uptake and acceptance in the DRC over a 54-year period (1970-2024). Our study captures critical transitions, including the post-smallpox eradication era and recent global outbreaks, to identify temporal trends, geographic disparities in this high-risk setting.

We conducted this review following PRISMA guidelines, systematically searching PubMed, Scopus, ScienceDirect, Web of Sciences, CINAHL, and Embase. Grey literature was also searched to ensure comprehensiveness. Using random-effects models, we calculated pooled estimates for vaccine uptake and acceptance rates, with prespecified subgroup analyses examining variations by: (1) period, (2) geographic region, and (3) type of participants. We quantified heterogeneity using I² statistics and conducted meta-regression to identify predictors of vaccination coverage heterogeneity. A p-value ˂ 0.05 was considered statistically significant.

Our analysis revealed a pooled Mpox vaccine uptake of 20.01% (95% CI: 7.45-43.75) with high heterogeneity (I² = 99.4%, p < 0.001), indicating substantial variability across studies. Vaccine acceptance was higher at 54.17% (95% CI: 20.82-84.16) with high heterogeneity (I² = 97.6%, p < 0.001). Temporal analysis showed a significant decline from 32.30% (95% CI: 14.62-57.75) coverage during 1970-2000 to 1.36% (95% CI: 0.29-6.11) in 2020-2024. Geographic disparities existed, with the Northwest regions achieving 47.11% (95% CI: 13.46-83.61) coverage compared to 5.47% (95% CI: 0.56-37.32) in Eastern conflict-affected zones. Meta-regression identified no significant predictors of coverage heterogeneity.

Despite moderate acceptance rates, actual Mpox vaccination uptake in the DRC remains low, with worsening coverage in recent years and substantial regional inequities. These findings underscore the urgent need for context-specific interventions to bridge the intention-action gap in this high-risk setting.