University of Guelph testing campus residences' wastewater to detect COVID-19

The University of Guelph is testing wastewater from its on-campus residents, where about 2,000 students are staying currently, for COVID-19.

Researcher says if they find the virus they 'can take steps to hopefully stop an outbreak'

A brick sign that reads University of Guelph.
The University of Guelph is testing wastewater from its on-campus residences, where about 2,000 students are currently staying, to check for COVID-19. (Kate Bueckert/CBC)

The University of Guelph is testing wastewater from campus residences for early signs of COVID-19 and expects to find out this week if new cases are cropping up.

The monitoring could help the school take early action against potential outbreaks of the novel coronavirus, said professor Lawrence Goodridge, who is leading the team of researchers carrying out the project.

"By testing wastewater, we capture anybody who is potentially infected regardless of whether they're showing symptoms or not," Goodridge said in an interview Monday.

"The idea is that if you tested it and you find it, then you can take steps to hopefully stop an outbreak from happening."

The testing detects levels of COVID-19 released in human feces, Goodridge said, and previous studies have shown that the virus appears in wastewater around a week before a person starts showing symptoms.

Testing began last week at five campus residences, where a total of about 2,000 people live, Goodridge said. Results are expected this week that could signal potential new cases, he said.

The testing cannot, however, tell where in a building the virus is coming from, only that someone living there might be infected, Goodridge said.

"All we can say is that at least one person in this building is shedding the virus," he said. "But once we know that, there's things that we can do."

For example, he said, the university can set up a mobile testing unit to individually test students from a certain residence and quarantine those found to be infected.

Goodridge said that approach has already been taken at several universities in the United States.

He noted, however, that the wastewater testing is just an additional tool to detect COVID-19 and is not meant to replace individual testing done by health units.

"We believe that because we've seen effective use of it elsewhere around the world, although there's still research questions to be asked, we can actually employ this right now," he said.