New spike in wastewater COVID-19 viral loads concerns researchers at U of S

Evidence of COVID-19 is increasing in the wastewater of Saskatoon, North Battleford and Prince Albert. (Richard Agecoutay/CBC - image credit)
Evidence of COVID-19 is increasing in the wastewater of Saskatoon, North Battleford and Prince Albert. (Richard Agecoutay/CBC - image credit)

After almost a month of declining numbers, researchers at the University of Saskatchewan say they have seen a jump in COVID-19 viral load in samples taken from wastewater treatment plants in Saskatoon, Prince Albert and North Battleford.

On Monday, researchers at Global Water Futures at the U of S said that evidence of COVID-19 had increased in Saskatoon by 51 per cent compared to the week before. Meanwhile, Prince Albert saw an increase of 86 per cent and North Battleford saw an increase of 58.7 per cent.

Researchers use the wastewater studies to predict whether COVID-19 case numbers will likely be increasing or decreasing in the near future.

The team had rated the viral load in all three cities as medium last week. However, the increases mean all three cities are now rated as high once again.

While a one-week increase is generally not enough to alarm the team, the researchers are concerned about a current spike in Ontario, where hospitalizations recently reached their highest point since February.

"The good thing about the Prairie area is that we are always a little bit behind what is happening in Ontario," said project manager Femi Oloye.

"So, that kind of gives us a good heads-up about what to expect here."

The increase of cases in Ontario is believed to be linked to new subvariants of the Omicron strain. As a result, researchers are working hard to try to discover which subvariants are most common in the area and use that information to better track COVID-19.

Right now, the team is working on genome sequencing to be returned from the National Microbiology Laboratory, which should provide concrete answers on what is present in the city.

"We know that the strain causing this increase is a form of Omicron, but exactly which of the sub-variants remains difficult to quantify," wrote toxicologist and former Canada Research Chair John Giesy.

"As can be imagined, with the rapid mutation of the SARS-CoV-2 virus, it is difficult to keep up."

As winter approaches, and with it a traditional increase in flu transmission, researchers say members of the public should not let their guard down.

"It just tells us that we should be more careful than ever," said Oloye.

"Before this, I was thinking we were getting over it. But what we are saying now is that we are actually not getting over it."

Researchers at the University of Regina had not yet released their weekly COVID-19 numbers Monday morning.