High Sensitivity of Facility-Level Wastewater Surveillance for Detecting Respiratory Virus Surges in Large Municipal Hospitals in New York City

The study examined wastewater monitoring from three hospitals in New York City from May 2024 to April 2026 using digital PCR. A total of 190 weekly samples were analyzed to detect SARS-CoV-2 and influenza A/B. Detection sensitivity was 38-42% for SARS-CoV-2 and 36-49% for influenza A/B, while specificity exceeded 72% for all pathogens. During respiratory seasons, sensitivity increased to 81% for SARS-CoV-2 and 81% for influenza A, reaching 100% during peak case weeks. Notably, influenza was detected in wastewater during summer 2024 without corresponding hospital cases, suggesting the presence of undiagnosed infections. The findings confirm the potential utility of hospital-based wastewater monitoring for tracking respiratory virus activity.