Community-Based Surveillance (CBS) for Strengthening Early Warning and Epidemic Preparedness in Urban Bangladesh: A Surveillance Protocol and its Implementation in Selected City Corporations of Bangladesh

Background: Bangladesh has well established facility based surveillance system for several diseases, but major gaps remain in detecting early signals at the community level. This protocol outlines the design and initial implementation of Community-Based Surveillance (CBS) in Bangladesh to establish an effective early detection and community reporting system for epidemic-prone diseases, to integrate CBS with existing national surveillance systems, and to identify operational challenges and opportunities for scaling CBS nationally. The initiative is being implemented through a collaborative partnership between the Institute of Epidemiology, Disease Control and Research (IEDCR) and the Bangladesh Red Crescent Society (BDRCS). Methods: Design of CBS will be initiated with a CBS assessment tool of the International Federation of Red Cross and Red Crescent Societies (IFRC) in 12 wards of three city corporations: Dhaka South, Rajshahi, and Sylhet City Corporations. The surveillance platform will engage trained community volunteers to cover selected community households. Priority disease syndromes such as influenza-like illness (ILI), acute watery diarrhea (AWD), suspected dengue, acute jaundice syndrome (AJS), and unusual human and animal health events are selected using criteria of public health relevance, intervention feasibility, and community detectability. Real-time reporting will be conducted using a mobile application linked to the IEDCR server. Data will be verified by Field Health Officers and escalated as needed. Dashboards will support ongoing analysis, and coordination mechanisms engaging health authorities at local and national levels. Expected Results: The CBS is expected to improve the timeliness and sensitivity of outbreak detection with initial focus to urban settings. It will provide community-level data to supplement facility-based surveillance and support rapid public health response. The initiative also aims to identify key operational, technical, and institutional factors needed for nationwide scale-up and integration into existing health emergency response frameworks. Conclusion: CBS in Bangladesh represents a promising approach to bridging the gap between communities and facility-based surveillance systems. By integrating CBS with digital tools, training local volunteers, and institutionalizing partnerships between government and non-government stakeholders, the initiative seeks to strengthen epidemic preparedness and response capacities. Findings from platform will inform future scale-up and contribute to regional and global best practices on community-led surveillance models.