Canary in the Coal Mine: Two-Year Wastewater Surveillance Results from an Indicator Community for Early Indication of IAV, RSV, Mpox, and SARS-CoV-2 in Five Surrounding Towns and Cities

An indicator community (IC) is a community in a larger population where pathogens can be observed earlier due to its unique characteristics, similar to the canary in the coal mine analogy. This study investigated using a strategically selected IC as an early viral indicator for the City itself and five surrounding towns and cities. Wastewater surveillance was carried out at least three times per week for 2 years to track IAV, RSV, mpox, and SARS-CoV-2. The IC, a university campus, was selected based on its closed-loop sewer system, population demographics, and high social connectivity. Results showed that wastewater surveillance at a well-selected IC can serve as an early indicator of emerging and seasonal viruses, providing a necessary lead time of at least 1 week for timely public health interventions. While wastewater treatment plants typically offer 1–3 days of early detection, the IC approach extended this window to 1–3 weeks. The IC approach was particularly useful as an early indicator of new surges and outbreaks of seasonal respiratory viruses. The results also showed a consistent presence of SARS-CoV-2 wastewater viral signal in all communities, unlike the seasonal respiratory viruses, indicating an ongoing low-level transmission and circulation of SARS-CoV-2 throughout the year.