RE-AIM evaluation of the national scale-up of community-based index case HIV testing in Guinea: Successes and challenges

In Guinea, an estimated 36% of people living with HIV remain unaware of their status, hindering progress toward the UNAIDS 95-95-95 targets (95% of people living with HIV to know their HIV status, 95% of those diagnosed with HIV to receive sustained antiretroviral therapy, and 95% of those receiving antiretroviral therapy to achieve viral suppression). This study evaluated the effectiveness, implementation fidelity, and sustainability of the community-based index case testing (ICT) strategy using the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework. We conducted a retrospective mixed-methods evaluation (2021–2024) across 17 districts supported by 26 community-based organizations (CBOs). Quantitative analyses included mixed-effects models, district-stratified descriptive analyses, and Spearman correlations. In parallel, 28 semi-structured interviews with key stakeholders were thematically analyzed in NVivo, guided by the five RE-AIM dimensions. Among 50,609 individuals reached, 8,112 underwent HIV testing, yielding a positivity rate of 8.4% (95% CI: 7.8 to 9.0), with 84.9% (95% CI: 81.9 to 87.6) successfully linked to care. Linkage to care was substantially higher among women (93.6%) and children (90.2%) than among men (14.1%). Adoption expanded from 3 to 17 districts between 2021 and 2023, while cascade performance displayed notable inter-district heterogeneity. Qualitative findings identified strong PMTCT mentorship, community trust, and counseling continuity as key facilitators, contrasted by recurrent challenges including commodity stockouts, financial dependency, and intrahousehold disclosure barriers. The ICT strategy was associated with expanding testing uptake and high linkage to care levels under routine programmatic conditions. Maintenance findings suggest that strengthening institutional integration of CBOs, reinforcing supply chain stability, and improving financing continuity may enhance programme sustainability. These findings provide context-sensitive operational evidence that may inform the adaptation of differentiated community-based testing strategies in comparable implementation settings.