Sask. COVID-19 sewage study an 'early warning system' for variants, says researcher

·2 min read
A look at the UV filtering system used at the City of Saskatoon's wastewater treatment plant.
A look at the UV filtering system used at the City of Saskatoon's wastewater treatment plant.

(Submitted by the City of Saskatoon - image credit)

Saskatoon's wastewater is once again going to be tested for the virus that causes COVID-19.

Researchers from the University of Saskatchewan were previously testing the wastewater, but ran out of funding. New funding will allow them to resume their work starting March 1.

Markus Brinkmann, an assistant professor at the U of S and a toxicologist, said the researchers are particularly interested in testing for some of the variants of the virus that have started to circulate.

"We're able to look at that in the wastewater as well and really try and see when we expect this to be really prevalent in the population here," he said.

Brinkmann said testing wastewater can show trends in virus transmission five to seven days earlier than testing people. Public health agencies can then use the data to inform their decision making.

Early warning system

The researchers will also be partnering with the Indigenous Technical Services Co-operative to test the wastewater in five First Nations communities.

"First Nations communities have been hit pretty hard with COVID early on, and outbreaks in smaller and more isolated communities can be really severe," Brinkmann said. "So having this sort of early warning system in place can be quite powerful to manage COVID there."

People who are infected shed virus traces through their feces, typically before they start presenting COVID-19 symptoms.

Testing the wastewater monitors the rate of change in COVID-19 spread on a population-wide basis, rather than individual cases.

Samples they take from Saskatoon's wastewater treatment plant are "basically a composite of the entire city," Brinkmann said.

"So if a person goes to the bathroom, for example, in the morning, you know, this might end up at different times from different neighbourhoods in Saskatoon. So you do still get a very good grasp of the entire population."

Having this sort of early warning system in place can be quite powerful to manage COVID. - Markus Brinkmann, University of Saskatchewan assistant professor

He said wastewater-based epidemiology is not a new idea but has become popular due to COVID-19 and he expects this type of research to remain.

"It can be used to screen potentially for influenza dominant strains to help and identify which kind of strains you should develop vaccines for," he said. "So I think it will be very useful in the future, even after COVID."

In the summer, the research was funded through the Global Water Futures program with buy-in from the province and the City of Saskatoon, but that funding ran out in the new year.

New funding from the Public Health Agency of Canada will allow them to continue their research for an additional six months.