Wastewater Surveillance for SARS-CoV-2 to Assess Citywide Trends:Variability, Sensitivity, and Correlation to Case Data

SARS CoV-2 Wastewater Testing - State of the Science
Oral Presentation

Prepared by S. McLellan, S. Feng, A. Roguet, J. McClary-Gutierrez, R. Newton
University of Wisconsin-Milwaukee, 600 E. Greenfield Ave, Milwaukee, Wisconsin, 53204, United States


Contact Information: mclellan@uwm.edu; 414382-1710


ABSTRACT

The COVID-19 pandemic has been challenging to track in communities because of the large numbers of asymptomatic or mildly symptomatic people and limited clinical testing resources in some areas. Wastewater surveillance for SARS-CoV-2 RNA can provide a population level assessment that is independent of clinical testing. With the exploding interest in this approach, there is a need to assess the reliability and precision of SARS-CoV-2 measurements in wastewater and evaluate how well these measurements capture diagnosed cases in the community. Importantly, public health officials could potentially use these data on a day to day basis, but the confidence in these measurements need to be established. In our work, we define variability in measurements, and attempt to answer what constitutes an increase in SARS-CoV-2 concentrations due to changes in infections vs. technical variability? Further, wastewater monitoring is resource intensive (upwards of $400 per sample); we have evaluated the optimal sampling scheme that balances resources with the ability to capture case trends. This information will be of interest for agencies and laboratories establishing programs in wastewater surveillance.