Wastewater Surveillance of SARS-CoV-2 at a Canadian University Campus and the Impact of Wastewater Characteristics on Viral RNA Detection.

SARS-CoV-2 levels in the wastewater of a Canadian university campus and their residence buildings were monitored to identify changes, peaks, and hotspots of COVID-19 transmission and search for associations with campus events, social gatherings, long weekends, and holidays. Wastewater signals largely correlated with clinically confirmed cases, often increased following long weekends, and decreased after the implementation of lockdowns. Furthermore, the impact of wastewater parameters on SARS-CoV-2 detection was investigated, and the efficiency of ultrafiltration and centrifugation concentration methods were compared. Results indicated more sensitive results with the centrifugation method for wastewater with high solids content and with the ultrafiltration method for low solids content. Wastewater characteristics from the building sewers were more variable than overall campus wastewater. Statistical analysis was performed to manifest the observations. Overall, wastewater surveillance provided actionable information and was able to bring high-risk factors and events to the attention of the decision-makers, enabling timely corrective measures.