Evaluating Active Versus Passive Surveillance under IDSR 3rd Edition in Central Africa: A Comparative Implementation Analysis of Outbreak Detection, Reporting Completeness, and Cost effectiveness (2018 to 2024)
Abstract:
Central Africa faces recurrent outbreaks of cholera, measles, yellow fever, Mpox, and viral haemorrhagic fevers, compounded by fragile health systems, insecurity, and limited laboratory capacity. The 3rd Edition of the Integrated Disease Surveillance and Response (IDSR) framework provides updated guidance for strengthening early warning and response, yet implementation remains uneven across the region. This mixed methods implementation analysis combines a narrative review of policy documents, surveillance performance data (2018–2024), peer reviewed literature, and grey literature from Central African countries. Data were synthesized using thematic analysis and a comparative assessment guided by IDSR core functions, IHR (2005) capacities, and health system resilience dimensions (absorption, adaptation, transformation). Active surveillance approaches, including community based surveillance (CBS), active case finding, event based surveillance (EBS), and proactive rapid response teams, substantially outperformed passive facility based models. Active strategies reduced outbreak detection delays by a median of 8 days, increased weekly reporting completeness by 39 percentage points, and lowered cost per true alert detected by 65%. Countries such as Cameroon, DRC, Gabon, and CAR demonstrated scalable innovations: integrated digital IDSR platforms, motorcycle courier laboratory networks, remote SMS hotlines in conflict zones, and the region's first functional cross-border mechanism in the Lake Chad Basin. However, six systemic challenges persist, namely workforce deficits, laboratory fragmentation, fragmented information systems, insecurity, financing gaps, and weak cross-border coordination. Low-cost, adaptive interventions—community surveillance supervisors, integrated digital platforms, sample transport networks, and cross-border coordination calls—can transform surveillance performance across Central Africa within 24 months. Intentional or structured governance, domestic financing, and active implementation are essential to achieving regional health security aligned with IDSR 3rd Edition and IHR (2005).References:
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