COVID-19 hasn't gone anywhere in Canada — and we could still see another surge

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COVID-19 may no longer be top of mind for Canadians, but there are still more cases and hospitalizations now than at some of the worst points of the pandemic — and while we may have moved on, the virus definitely hasn't.

Canada has lifted almost all public health measures as COVID-19 levels continue to drop from the peak of the devastating Omicron wave that overwhelmed testing capacity and fuelled a record surge in hospitals across the country.

But a recent rise in global COVID-19 cases, the spread of a more contagious Omicron subvariant and a spike in early surveillance signals across Canada has experts increasingly worried we could be on the verge of another surge.

"Following several weeks of declining activity nationally, the average daily case counts are now levelling off," Canada's Chief Public Health Officer Dr. Theresa Tam said during a news conference Friday. 

"As public health measures ease, increased levels of transmission are not unexpected since the SARS-CoV-2 virus is still circulating widely." 

A steep drop in testing across much of the country has blurred the picture of how much the virus is circulating, yet other metrics such as wastewater data and hospitalizations suggest COVID-19 levels remain higher than at many other points in the pandemic.

More than 4,000 Canadians are currently hospitalized for COVID-19, and although that total has been dropping from a January peak, it's still the highest since April 2021 — and almost as high or higher than the peak of every other wave. 

"Even though we're in a much better place now than we were one and two months ago, there's still a lot of COVID around and there's still a lot of people in hospital with COVID," said Dr. Isaac Bogoch, an infectious diseases physician at Toronto General Hospital and member of Ontario's COVID-19 vaccine task force. 

"Sadly, this is not over yet."

The silver lining for Canada is that our combination of high vaccination rates and infection-based immunity will ensure most Canadians are protected against serious illness. 

Yet the highly-contagious Omicron variant — including the BA.2 subvariant that's on track to dominate new cases — is proving able to infect people more easily than its predecessors.

There are also concerns over waning immunity, with studies showing protection from infection can decline within months even after a booster — while protection against hospitalization appears to be holding up. 

A recent report from the U.S. Centers for Disease Control and Prevention (CDC) found protection from infection dropped from 69 per cent within two months of a second dose to just 37 per cent after five months.