Wastewater Surveillance for COVID-19
Since the start of the COVID-19 pandemic in spring 2020, studies have shown that a significant proportion of people with COVID-19 infections shed the virus in their stool, sometimes even before their symptoms start. Wastewater surveillance for COVID-19 tests for the presence of genetic material (known as RNA) of the SARS-CoV-2 virus in wastewater. This approach has the advantage of capturing both positive cases and asymptomatic cases in the community since it is not limited by personal behaviour (e.g., choosing to not get tested). While wastewater surveillance does not provide information on the number of active cases in a population, it can indicate the presence and trends of COVID-19 in the community, sometimes in advance of clinical indicators. In this way, wastewater surveillance is a complimentary tool for public health units to identify outbreaks and inform decisions on where and how to mobilize resources.
A multidisciplinary team of UWRC researchers, co-led by Dr. Kimberley Gilbride (Chemistry and Biology) and Dr. Claire Oswald (Geography and Environmental Studies), have been conducting wastewater surveillance for COVID-19 since summer 2020 in partnership with the Province of Ontario, Toronto Public Health, Toronto Water, and Unity Health (St. Michael’s Hospital). As part of the Province of Ontario’s Wastewater Surveillance Initiative (WSI), external link, they are collecting and testing wastewater from one wastewater treatment plant, six communities (or neighbourhoods), and eight facilities (e.g., shelters, long-term care homes, hospitals, campus residences) in the City of Toronto. The data they generate is shared directly with the Province, Toronto Public Health, and facility staff two times per week and has led to several public health interventions since summer 2021. The UWRCs research and service on wastewater surveillance has been funded through Ryerson University’s Rapid Response Fund, NSERC Alliance COVID-19, external link fund, the Province of Ontario, and the Public Health Agency of Canada’s COVID Immunity Task Force, external link.