Calgary's active COVID-19 cases leapt 331% in one month

Cases of COVID-19 in Calgary have risen sharply and an infectious disease expert says the province needs to quickly act to ensure those numbers don't continue to grow out of control. 

Active cases in the city have grown by 331 per cent since Oct. 1, and Edmonton has seen cases grow by 203 per cent during the same time period. 

In the last week, the city quickly surpassed Edmonton's numbers — Calgary reported 1,642 new cases to Edmonton's 1,484. Both cities now have more than 2,500 active cases each. 

"I think history would judge us harshly if we actually don't really address [the numbers] quite clearly and firmly, and ... that is something that I think we'll be looking for over the next few days," said Dr. Lynora Saxinger, an infectious disease specialist at the University of Alberta. 

Calgary has a rate of 161.7 cases per 100,000 people. 

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Saxinger said if the high daily case numbers continue, there could be problems for those who need to access health-care services — COVID-19 patients or not. 

There are currently two Calgary hospitals with outbreaks, and two other hospitals are on watch. There are 101 cases linked to the outbreaks, 13 of whom have died. 

The city is also seeing a high positivity rate among those tested, at seven per cent — it's remained around the two per cent mark for most of the pandemic — numbers Saxinger called "truly alarming" that could indicate there are cases in the community health officials aren't aware of. 

The World Health Organization has recommended a positivity rate of five per cent for two straight weeks before loosening restrictions to slow transmission.

Tom Sampson, chief of the Calgary Emergency Management Agency, said in a video posted to Twitter that Calgary's rate of transmission (which is at R 1.2, meaning each person with COVID-19 spreads it to 1.2 others) is unsustainable.

"Think about it like a budget, if you earn a dollar and spend a dollar, you'd be OK. But if you earn a dollar and spend $1.20, you'd have a problem," he said. 

Saxinger said one response could be a "short and sharp" lockdown, to reassure people that there is an end in sight — kind of like throwing a wet blanket onto a fire. 

"That kind of blunt instrument can really get us to the point of a reset ... if we're playing catch-up all the time and adding restrictions as things aren't going well, you run the risk of actually having a much longer, much higher epidemic peak," she said. 

Of the new cases across the province, 53 per cent have an unknown source of transmission. 

Calgary Mayor Naheed Nenshi said Tuesday that the new numbers are "extraordinarily troubling."

"We are on track as a province to having 1,000 new cases a day as soon as the end of this week … we are not just above where we were in the spring, we are far above where we were in the spring," he said.

"A vaccine is months away, we need to redouble our efforts to avoid a lockdown, to look after one another, to flatten this curve."