Covid-19 Monitoring Using Wastewater-Based Epidemiology: The Promise and Peril of Seeking Useable Data in a Pandemic

Abstract

We evaluated sampling design in wastewater-based epidemiology to monitor SARS-CoV-2 RNA signal, with a focus on sampling site selection. Sampling in wastewater collection systems ranged from locations that were highly granular (i.e., individual buildings) to large wastewater treatment plants with city-scale catchments. Potential data uses and major considerations for each sampling method are discussed. Our study demonstrates sampling at varying degrees of granularity to be viable tools for pandemic response, with both sampling location and data applicability varying significantly based on location type sampled. Wastewater treatment plant data allows for population level trending that provides an early warning sign of increased disease burden community wide. Sampling at individual buildings can facilitate a direct public health response through follow-up patient testing and/or providing early warning to allow an employer to respond to an outbreak at a warehouse or work camp. Sampling within the wastewater collection system presents a novel epidemiologic tool that could allow for early warning of neighbourhood outbreaks to inform local pandemic response(s) and enable case-finding.