Wednesday, January 12, 2022

'We've never seen this kind of transmission before': Omicron cases dwarf official reports across Canada

Tyler Dawson 
With Omicron cases skyrocketing across Canada, figures from Alberta suggest that the official numbers, rolled out in data sheets and at press conferences, don’t capture the full extent of the fifth wave.

Alberta Health Services staff conduct drive-through COVID-19 tests at the Richmond Road testing site in Calgary on December 30, 2021. Gavin Young/Postmedia

On Monday afternoon, Dr. Deena Hinshaw, Alberta’s chief medical officer of health, said that there are roughly 57,000 active COVID-19 cases in the province.

“We’ve never seen this kind of transmission before,” said Hinshaw, adding that anywhere you go, someone is likely to have COVID-19. “We can’t stop this, but we still can slow the spread.”

The actual figure for active cases in Alberta could be at least 10 times higher, Hinshaw said, shedding light on the extent to which Omicron is spreading, undocumented by the strained testing system.

“It’s very clear with a 40 per cent positivity rate, transmission is higher than it’s ever been before and we should assume that, at minimum, we’re seeing about 10 times or more the number of cases than we’re diagnosing through PCR,” Hinshaw said.

Hinshaw said she was unable to provide an actual figure to go with that ratio, but 10 times Alberta’s active COVID cases would be about 570,000 cases, which eclipses the official active case counts for the entirety of Canada.

The Public Health Agency of Canada says that all of Canada currently has 404,000 active cases.

Isaac Bogoch, an infectious diseases expert at the University of Toronto, said it’s not surprising there’s a gap between the actual number of cases and cases found by testing. He said such a phenomenon likely exists everywhere in the country.

“No matter where you are, there’s always going to be a difference in cases captured by PCR versus the total number of cases; there’s always that delta,” Bogoch said. “I think it would be a fair assessment to say that everywhere in the country, the true number of cases dwarfs the number of cases that are detected by the limited testing capability that we have right now.”

It’s not clear what percentage of cases other provincial governments believe they are catching — and not catching — with their testing.

In recent weeks, a number of provinces across Canada have limited access to polymerase chain reaction testing — the more accurate testing provided by governments — to vulnerable populations, in order to conserve resources. A consequence of this decision is that testing captures a smaller percentage of the total number of positive cases while, by limiting testing to those who are most likely to be ill, amplifying the positivity rate.

British Columbia, Ontario, Alberta and Quebec have all limited testing to people at risk of severe disease or those who work around vulnerable populations, including at long-term care homes.

This comes as testing capacity, given the sheer number of active cases, has been unable to cope with demand. There are staffing shortages in the health-care sector, an issue across the country, because of Omicron, and other sectors of the economy, too.

“There’s a massive burden of community level infection and eventually it runs out of tinder and cases start to drop,” said Bogoch.

Officially, in Ontario there are roughly 140,000 active cases. In Quebec, which has instituted strict lockdown measures, the active case count sits just above 100,000. British Columbia has nearly 38,000 active cases.

“This is the nature of Omicron. It is a hyper-contagious disease that is ripping through the population,” said Raywat Deonandan, a global health epidemiologist at the University of Ottawa.

So far, in Alberta, hospitalization and intensive care numbers have not reached heights seen in the early fall, when the province nearly had to implement a triage protocol determining who would receive hospital care, as capacity limits had been strained to their breaking point.

Yet, said Bogoch, we know that some small percentage of those who catch COVID-19 will end up needing medical attention at a time when the system is dealing with burnout, staff shortages and overall capacity concerns.

“We know a very small percentage of people who get this infection will actually need to use health-care resources. However, a small percentage of a massive number of infected people still ends up being a lot of people requiring health care,” Bogoch said.

• Email: tdawson@postmedia.com | Twitter: tylerrdawson

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