Ontario, Quebec have entered another COVID-19 wave. Could Saskatchewan be next?

An epidemiologist says it's "a matter of weeks" before Saskatchewan is hit with its next wave of COVID-19, as the fast-spreading Omicron BA.5 subvariant is already dominating other jurisdictions.

"This next surge of cases of COVID-19 is coming sooner than we had expected," said Nazeem Muhajarine, a professor of community health and epidemiology at the University of Saskatchewan.

On Wednesday, Ontario's top doctor confirmed that the province has officially entered its seventh COVID wave, driven by the BA.5 subvariant. Quebec's seventh wave has also begun, officials said Thursday. 

Saskatchewan has experienced previous waves of COVID weeks after other provinces. 

The BA.5 subvariant is also the dominant variant in the United States, accounting for 53.6 per cent of variants as of July 2, according to the U.S. Centers for Disease Control and Prevention.

The BA.4 sublineage made up 16.5 per cent of the variants in circulation in the U.S., for a combined 70.1 per cent of variants, the latest data showed.

'Inevitable' BA.5 will be dominant strain

BA.5 has so far only made up a small percentage of variants in Saskatchewan, according to the most recent data shared by the province. But the data is weeks too old. 

The last report the government shared, covering the week of June 19 to 25, showed the BA.2 subvariant accounted for 95.2 per cent of variants, while BA.5 accounted for 3.6 per cent — an increase of 2.5 per cent from the previous week — and BA.4 accounted for zero per cent. 

The province has stopped sharing weekly COVID information and will now do so monthly. 

Muhajarine said that by the time the next report is released, on July 21, BA.5 will likely be the dominant variant. 

Dr. Cory Neudorf, an epidemiologist and interim senior medical health officer with the Saskatchewan Health Authority (SHA), agreed.

"It's pretty much inevitable at this point that it will become the dominant strain over the summer," Neudorf said Thursday.

"How fast that increase will be during the summer is unclear at this point. It really depends on what people's behaviour is like."

Neudorf pointed out that Saskatchewan's COVID situation differs from other jurisdictions such as Ontario.

"We do have more people who've been more recently infected, but we have fewer people who've been fully immunized," Neudorf said.

"But in all likelihood what we'll see is a slow reduction to this decline that we've been seeing and we'll start to see more of a plateauing again, followed by a bit of an increase in cases."

The Ministry of Health said officials continue to monitor COVID trends. 

"Any recommendations for additional measures will be made based on the best information available," the ministry wrote in a statement Thursday. 

Vaccinations 

Evidence shows the BA.4 and BA.5 subvariants are better at evading people's immunity, either from vaccination or from previous infections, but vaccination remains the best way to avoid getting seriously ill.

Based on federal data collected in April and May of this year, when Omicron activity was very high in Canada, people with a booster shot were five times less likely to be hospitalized and seven times less likely to die from the virus than people who were not vaccinated, Dr. Theresa Tam, Canada's chief public health officer, said last Thursday.

Canada is lagging behind other developed countries in booster dose coverage. Health Minister Jean-Yves Duclos said last Thursday that only 60 per cent of adults who got their first two doses have gone back for a third. The rates are substantially higher in other countries including Japan and the U.K.

In Saskatchewan, the rate is much lower than the national average. As of June 25, 52.8 per cent of adults with their first two doses have received at least one booster. The booster vaccination rate has been hovering near the 50 per cent mark since February. 

Currently, only Saskatchewan residents aged 50 and older are eligible for fourth doses.

On Tuesday, Premier Scott Moe told reporters that he doesn't know when eligibility will be expanded. 

Neudorf and Muhajarine recommend people get vaccinated or boosted if they haven't yet, wear a mask in crowded indoor spaces and stay home when they're sick.