Donor Dependency and Health-Service Sustainability: A Meta-Analysis & Systematic Review of the Great Mundri, Western Equatoria State, South Sudan

South Sudan's health sector relies heavily on external support, yet the magnitude of donor dependency and its impact on service sustainability remains poorly quantified. This systematic review and meta-analysis examined donor dependency in Great Mundri County's health system and its effects on service coverage. A PRISMA-guided systematic search of MEDLINE, Embase, Web of Science, Scopus, and Google Scholar (2005-2024) yielded 1,243 records. After screening, 37 studies met inclusion criteria, with 12 containing extractable quantitative data for meta-analysis. Random-effects models generated pooled estimates and assessed heterogeneity. Donors financed 78% (95% CI 70-85; I² = 64%) of recurrent health-sector costs in Great Mundri. Donor withdrawal was associated with significant declines in skilled birth attendance (pooled decline: 23 percentage points, 95% CI 15-31), childhood immunization coverage (pooled decline: 19 percentage points, 95% CI 12-26), and essential drug availability (pooled decline: 34 percentage points, 95% CI 26-42). Community engagement initiatives showed protective effects, reducing the magnitude of service decline by 40-60%. Nearly four-fifths of health financing remains donor-derived, with abrupt funding transitions leading to substantial reductions in service coverage. Enhanced community engagement and gradual donor transition strategies may mitigate negative impacts on health service sustainability in fragile settings.