Saskatchewan’s deputy chief medical health officer says she expects the highly contagious BA.5 Omicron COVID-19 subvariant to become dominant in the province, which health authorities say has the potential to result in increased pressure on health care resources.
“We expect that over time it will replace BA.2 as the dominant lineage of Omicron in the province.”
According to the World Health Organization, BA.5 has already become dominant globally and is likely helping contribute to what is now a fifth straight week of increasing global cases.
Meanwhile on June 30, Dr. Theresa Tam said in a statement that “it is reasonable to expect that we could see an increase in case numbers in the coming weeks as a result of the BA.4 and BA.5 sub-lineages increasing in proportion.
Kryzanowski didn’t comment specifically on whether or not she thinks Saskatchewan is in the early stages of its own summer wave, but said overall BA.5 trends are alarming.
“What we are concerned about is that an increase in cases might also result in an increase in pressures on the acute care system,” she said, adding that those with conditional health risks should be taking precautions.
“The advice for people right now is for people is to be aware that COVID-19 continues to transmit throughout the province.”
But with the province announcing a move to monthly reporting last month, new provincial epidemiological data won’t be available to confirm the trend locally until July 21.
Still, there is some evidence that the BA.5 subvariant is rising in Saskatchewan.
The province’s latest update showed that for the reporting period of June 19 to 25, BA.5 accounted for just 3.6 per cent of sequenced virus samples.
But the most recent wastewater data analyzed at the University of Saskatchewan showed that BA.5 accounted for 14.2 per cent of the total viral load in Saskatoon and 14.8 per cent in North Battleford though only 2.17 per cent in Prince Albert.
The data also showed week-over-week increases in total viral load in all three cities.
The University of Regina’s latest wastewater analysis report, released July 11, shows higher viral loads than in previous weeks and that trace amounts of BA.5 have been detected since late May.
The update also states, though, that “preliminary data suggest that the levels might not increase further in the following week.”
Researchers note that while wastewater data has been reliably used to predict the direction of new case trends in the seven to 10 days following when a sample was taken, the magnitude of change in cases is not always proportional.
Nationally, as of June 19, government of Canada data shows BA.5 represented 38.4 per cent of all variants sequenced. BA.4 represented 9 per cent of sequenced variants in the June 19 epidemiological update. BA.2 still represents 52 per cent of sequenced variants.
And south of Canada in the United States, U.S. Centers for Disease Control (CDC) data shows BA.5 has now become the dominant strain. As of July 9, it accounted for an estimated 65 per cent of all circulating variants.
Epidemiologist Dr. Nazeem Muhajarine said more frequent reporting is needed to help inform Saskatchewan residents as they make plans for their summers.
“The biggest thing right now is that we have no real idea of how BA.5/BA.4 is spreading in Saskatchewan,” he said in an email.
“We have stopped reporting COVID-19 data and we are in the dark right now when it comes to knowing about these new variants. We are not doing enough testing, certainly not random testing and in sufficient numbers.”
He noted Saskatchewan is the only province that has completed the move to monthly reporting so far.
“With the most transmissible BA.5/BA.4 now threatening to drive a new wave, the province needs to revisit its reporting frequency,” Muhajarine said.
“‘What gets measured, gets managed. We need to measure COVID-19 in this province to manage it.”
He added that, “Some reports are saying that BA.4/BA.5 may resemble Delta to some degree with regard to affecting lower respiratory tract and the lungs compared to other Omicron variants.”
In response to a question about expanding second booster dose eligibility, the Saskatchewan Ministry of Health said in a statement that “fall booster dose planning is underway now.”
“Note that includes not only COVID-19 vaccine supply and distribution, but the necessary human resources that are required to deliver a significant booster campaign as well as the regular fall influenza campaign.”
“Details of the fall campaign will be announced once the appropriate planning is complete.”