Wastewater study shows COVID trending down in Saskatoon, increasing in Prince Albert and North Battleford

Analysis ofSaskatoon's wastewater reveals the city has likely passed the peak of the pandemic's fifth wave which saw the highly transmissible Omicron variant infect thousands of people each week and push COVID-19 hospitalizations to record-breaking highs across the province.

"The concentrations of virus are still greater than they ever were during the fourthwave. After bouncing around a bit, they are trending downward," said John Giesy, a University of Saskatchewan professor and principal investigator forGlobal Water Futures.

The program monitors wastewater in Saskatoon, North Battleford and Prince Albert and tracksthe presence of SARS CoV-2, the virus responsible for COVID-19.

In Saskatoon, evidence of COVID was up 19 per cent for the week ending February 2, compared to the previous week according to analysis of the city's wastewater.

Giesy said the level of COVID detected in Saskatoon's wastewater peaked about three weeks ago and has been trending down since that time.

"The numbers now are still greater than anything we saw in previous waves. So while the overall trend line is down, it's still really high. It means there's still a lot of infected people," Giesy said.

The situation is different inNorth Battleford and Prince Albert.

Those cities saw an increase of 29.5 per cent and 28 per cent respectively over the previous week.

"The rate they're going up has slowed. That means they're nearing their peak," Giesy said, noting the previous week those cities were up close to 400 per cent.

He said North Battleford and Prince Albert are likely about two weeks away from reaching the peak of the fifth wave.

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The wastewater analysis has helped epidemiologists, scientists and the general public parse out the extent to which COVID-19continues to spread in the province as access to PCR testing becomes restricted and the daily Saskatchewan Health Authority dashboard is discontinued.

The dashboard was a go-to for many people to get daily updates on the number of people testing positive, dying and being hospitalized with COVID-19 each day in Saskatchewan.

That information will now be provided weekly instead of daily.

Nazeem Muhajarine, an epidemiologist with the University of Saskatchewan, said it is critical to understand the spread of COVID-19 in the community so public health officials can introduce measures to stop its spread if needed.

"We cannot let go of any of the metrics, in fact we need to add more."

Muhajarine said removing the daily COVID dashboard makes it more difficult to understand how much COVID is spreading in the community.

"I think it's too premature. You know, we are still in the fifth wave."

He said that the study of wastewater will become even more critical in understanding community transmission of COVID-19 in the absence of widespread testing.

Giesy agreed, but said Global Water Futures is only funded to study COVID in wastewater until March 31.

"I think we're the only game in town now," Giesy said, adding he is meeting with public health officials later this week to discuss potentially extending the project.

He said the province is also considering expanding the study of wastewater to other centres.

Giesy and his team collect wastewater samples Sunday, Wednesday and Friday each week in Saskatoon, Prince Albert and North Battleford and compare the average of those three days to the previous week.

His data shows a consistent spike in COVID for the past several Fridays.

"The numbers we have for Friday always pop up and then they go down on Sunday and Wednesday. It seems as though people are getting infected through work during the workweek. Work and school."

Recently, wastewater testing has revealed the potential presence of Omicron BA-2, a new variant in Saskatoon's wastewater that is 1.5 times more transmissible than the Omicron strain, Giesy said.

He said the new Omicron variant is already established in the United Kingdom and Denmark as well as some parts of Asia.