Calgary

Here's what the COVID-19 numbers are telling us 18 days after Alberta lifted restrictions

With mandatory masks, vaccine passports and capacity limits in entertainment venues firmly in the rearview mirror for most situations in Alberta, COVID-19 numbers are showing a mixed picture.

Wastewater data shows levels well below December and January but well above zero

Alberta Premier Jason Kenney removes his mask as he gives a COVID-19 update in February. (Jeff McIntosh / The Canadian Press)

With mandatory masks, vaccine passports and venue capacity limits firmly in the rearview mirror for most Albertans, COVID-19 numbers are showing a mixed picture.

Far from gone, the virus remains persistent in many parts of the province.

Wastewater data — the detection method able to give the most advanced picture of where SARS-CoV-2 is going — shows virus counts are levelling off after a steep climb and descent in the Omicron wave.

The latest readings on the COVID-19 wastewater dashboard are higher than some of the earlier peaks in Alberta's two largest urban centres as well as in a few small communities.

"It really just does seem to be, you know, hanging around, not taking off. Hopefully, it stays that way," said Casey Hubert, a geomicrobiology professor at the University of Calgary who works with the group collecting wastewater samples in Calgary.

The Y axis denotes the number of SARS-CoV2 RNA particles detected per millilitre of wastewater. This chart should only be interpreted as a measure of progress against itself and not used to compare with other cities or measurement sites. (Rob Easton/CBC)
The Y axis denotes the number of SARS-CoV2 RNA particles detected in each sample. The numbers show the first number multiplied by 10 to the power of the small number above. For example 2.1 x 10¹⁵ written out in full is 2,100,000,000,000,000 or 2.1 quadrillion RNA particles detected. (Rob Easton/CBC)

While numbers have jumped in recent days in Calgary, Banff, Lethbridge and Medicine Hat, Hubert says there hasn't yet been three consecutive days of increases to be sure there is a trend in Alberta.

Edmonton, conversely, has not seen any change up or down.

Jason Kindrachuk, an assistant professor of microbiology at the University of Manitoba, says with restrictions gone for almost three weeks, increasing numbers aren't unexpected, even if it is too early to tell whether the numbers are just noise.

"Looking at Europe right now, we're seeing increases in cases," he said. "And that also ties back to the loosening of restrictions and, of course, concerns about vulnerable populations with immune waning and all these different factors coming in together."

Daily new infection, hospitalization, ICU and daily death numbers in Alberta all continue to decline.

However, the positivity rate is still hovering around 20 per cent, and the number of official active cases remains higher than at earlier lows in the pandemic.

Both these numbers are influenced by province limiting of tests to those in high-risk settings such as long-term care facilities. The number of active cases are higher than the official number as those who have contracted COVID-19 are not getting a PCR test administered by the province and therefore don't show up in official figures.


The numbers in Europe have been influenced by the new subvariant of Omicron known as BA.2, which is said to be even more transmissible than the original strain of Omicron, or BA.1.

It is unclear whether the emergence of BA.2, which recently accounted for a quarter of new cases in Alberta, is the reason why overall COVID-19 levels haven't dropped further, says Hubert.

Alberta has one of the most sophisticated genome monitoring programs in the world, but Alberta Health currently only sequences a proportion of cases, according Dr. Lynora Saxinger, an infectious disease specialist at the University of Alberta.

The wastewater tracking team is able to genetically sequence variants found in the sewers. However, to properly know the proportions of one variant versus another requires extra resources. That's something the team was able to do as Omicron displaced Delta, but they have yet to do so for Omicron's subvariant.

"It makes one wonder if it could be the decline of one variant and the rise of another," said Hubert. "We're watching very closely to see if there's going to be another spike like we saw right before Christmas with BA.1. So far, there hasn't been, and we're very hopeful that that will remain the case."

Reporting once a week

Alberta Health announced this week that it would no longer report daily COVID-19 numbers, moving to a weekly schedule.

Saxinger has mixed feelings about the change but ultimately doesn't think it's a bad thing.

"I can understand why some people would kind of feel like we're losing some information there," she said. "But if we are going to pay attention to trends, and actually look at that weekly data, I don't see it as being necessarily dangerous."


The daily information does help keep attention on the virus, with many Albertans regularly looking at the numbers to see whether they are up or down, she says.

But moving to weekly figures won't affect analysis in the long run, she says, because even with daily numbers, you still want to look at the wider trend over a few days or a week.

"It is a shift and I think we can deal with it."

Wastewater data, on the other hand, is released three times per week and is a leading indicator to many of the testing and case numbers released by the province, meaning it can forecast what is to come.

According to Hubert, the trend can be seen in the wastewater data by looking for several points in a row going in one direction or the other and at the trend line included in the charts.

"I live in Calgary," he said. "I check the Calgary data as if I'm checking the weather, and that informs my own personal decisions about about how I'm going to approach my day or my week."

Moving further into the pandemic, wastewater numbers will become increasingly important as people look for signs for what's to come, according to Hubert.

Kindrachuk says the lack of public health mandates puts more of the onus on the public to read the numbers and follow recommendations, rather than orders.

Albertans can still make choices in regard to masking, physical distancing and monitoring one's own health situation by taking rapid antigen tests and staying home if they feel sick.

"I think right now we're in a process of seeing a lot of things going back to the individual," he said, "and us now having to say, OK, what do I feel comfortable with and what is my return situation?"

With files from Jennifer Lee

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