Strengthening diagnostic capacity for viral hemorrhagic fevers in Forest Guinea: advances in case detection and surveillance

Abstract Background Viral hemorrhagic fevers (VHFs) remain a major public health threat in resource-limited settings. The 2014–2016 Ebola virus disease epidemic exposed critical gaps in laboratory preparedness and diagnostic capacity in most-at-risk countries, including Guinea. Sustainable in-country laboratory capacity is essential for early detection and rapid response to VHF outbreaks, including Lassa fever. Methods A long-term laboratory capacity–strengthening programme was implemented in Guinea, combining training of local personnel, provision of molecular diagnostic tools, and ongoing technical and financial support. In 2017, a permanent VHF diagnostic laboratory was established in Guéckédou. In 2021, a second laboratory in N’Zérékoré was strengthened, expanding coverage in Forest Guinea. Both laboratories provided free access to VHF diagnostic services for suspected cases and contributed to routine surveillance. Testing activity and confirmed cases from 2017 to 2024 were analyzed. Findings Between 2017 and 2024, 4683 samples from suspected VHF cases were tested across the two laboratories. The laboratories supported rapid outbreak detection and case management, notably during the 2021 resurgence of Ebola virus disease and the Marburg virus disease outbreak in Guinea. Prior to this programme, local laboratory capacity for routine Lassa fever detection and reporting was absent in endemic areas of Forest Guinea. Between 2020 and 2024, 30 laboratory-confirmed Lassa fever cases were identified, with a case fatality rate of 67·9%. Interpretation The establishment of locally embedded laboratory infrastructure and a trained workforce improved VHF preparedness, surveillance, and response in Guinea. Beyond providing new insights into Lassa fever epidemiology, this programme shows how sustained investment in laboratory capacity can strengthen early detection, prevention strategies and health system resilience in VHF-endemic settings. Funding German Federal Ministry of Health, German Center for Infection Research