Leveraging the influenza sentinel surveillance platform for SARS-CoV-2 monitoring in Bangladesh (2020-2024): a prospective sentinel surveillance study

Journal article

BackgroundThere is limited global evidence on whether influenza sentinel surveillance platforms can be effectively adapted for long-term SARS-CoV-2 monitoring in low-resource contexts. We explored the utility of the hospital-based influenza sentinel surveillance (HBIS) platform for monitoring SARS-CoV-2 in Bangladesh by comparing SARS-CoV-2 detection in HBIS platform with national COVID-19 platform and assessing how its integration into influenza surveillance aligns with national trends.MethodsFrom March 2020 to December 2024, we analysed data from patients with severe acute respiratory infection (SARI) and influenza-like illness (ILI) enrolled in HBIS. Socio-demographic and clinical data were recorded, and nasopharyngeal and oropharyngeal swabs were tested for influenza and SARS-CoV-2 using rRT-PCR. Whole-genome sequencing was performed on a subset of SARS-CoV-2-positive samples. Data from national COVID-19 platform were obtained from the Directorate General of Health Services, Bangladesh, and were compared with HBIS platform data using epidemic curves and Pearson correlation analysis.FindingsAmong 25,366 (SARI: 20,226; ILI: 5140) patients, 13.0% (3310) tested positive for influenza, 6.6% (1680) for SARS-CoV-2, and 0.2% (43) were co-infected. SARS-CoV-2 positivity in HBIS (6.8%), including 0.2% co-infections, was lower than the national average (13.1%), but showed a strong correlation with national trends (Pearson r = 0.86, P < 0.001). Sequencing of 234 SARS-CoV-2 strains detected the beta and delta variants in April and May 2021, respectively, and omicron subvariants circulating from 2022 to 2024, aligning with the national COVID-19 platform.InterpretationSARS-CoV-2 positivity trends in HBIS platform closely aligned with the national COVID-19 platform, demonstrating its potential as a sustainable platform for COVID-19 monitoring. Our findings underscore the feasibility of influenza sentinel surveillance as an early warning system for future COVID-19 outbreaks or other respiratory viruses of pandemic concern in Bangladesh and similar settings.FundingCenters for Disease Control and Prevention (CDC), Atlanta, Georgia, USA (U01GH002259).

Authors: Islam, MA; Hassan, MZ; Akhtar, Z; Bhuiya, S; Shuvo, TA

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Elsevier
• Journal: The Lancet Regional Health – Southeast Asia
• Volume: 41
• Pages: 100657
• Publication date: 2025-08-21
• Acceptance date: 2025-08-04
• DOI: 10.1016/j.lansea.2025.100657
• EISSN: 2772-3682
• ISSN: 2772-3682
• Pmid: 40896357
• Language: English
• Keywords: Influenza; Monitoring; Surveillance; Bangladesh; Covid-19; Integration; Sentinel Surveillance; Sars-cov-2