Canada has recorded its 30,000th COVID-19 death since the pandemic began in early 2020, surpassing a grim milestone just as the country braces for the potential fallout of surging infections driven by the Omicron variant.
Ontario reported nine more COVID-19 deaths Thursday morning, pushing Canada's total just over 30,000 as Ottawa and some provinces tightened public health measures to stave threats posed by a more transmissible virus.
It took Canada nine months to reach 10,000 COVID-19 deaths last November, but the toll doubled to 20,000 just two months later in January 2021 -- a leap that occurred before enough vaccines had been administered to have an impact. The country surpassed 25,000 COVID-19 deaths in May.
Since then, experts say vaccines have significantly reduced the number of people dying from the virus daily, with some estimates suggesting between 75 per cent and 90 per cent fewer deaths in each age group, compared to what would normally be expected.
Chief public health officer Dr. Theresa Tam said the arrival of vaccines a year ago -- Canada administered its first jabs on Dec. 14, 2020 -- resulted in a "dramatic shift" in the country's COVID-19 epidemiology, with a particular drop in mortality rates.
The trajectory "dropped dramatically after the vaccines came into effect, and continues to be at a sustained at a lower level," she said in a news conference Monday.
Dr. Tara Moriarty, a researcher at the University of Toronto, estimates vaccines "likely saved more than 476,000 lives in Canada to date."
Roughly 40 per cent of Canada's total COVID-19 fatalities have occurred since January and Moriarty said the vast majority of those 2021 deaths were among the unvaccinated.
She said the much faster spread of the Delta variant, which took off in Canada in the spring, contributed to more severe illness, particularly among those not immunized, adding there may be more unreported deaths from undetected cases.
"There's a lot more spread happening, people are more relaxed, a lot more people are getting exposed," Moriarty said. "Cases aren't a great indicator anymore. A lot of cases aren't being detected."
As the more transmissible Omicron variant circulates more widely in Canada, experts expect vaccination will continue to play a large role in keeping people out of hospitals and intensive care units.
Provinces have ramped up third-dose rollouts amid the Omicron threat, though scientists are still racing to learn how quickly the variant spreads, whether it causes more severe disease and how much it might evade vaccine protection.
Moriarty said third doses will be "crucial" in topping up immunity that naturally wanes over time after the first two jabs.
"Even a shift of 10 per cent (in protection) one way or the other can have enormous impact on the spread of an epidemic," she said. "We'll have to wait and see the impact of (third doses).
"But at this point, the threat of really rapid spread is so high that it's really crucial for people to get their boosters."
Moriarty said that even if Omicron proves less severe than Delta, its growing circulation means the virus will find vulnerable people, including unvaccinated children and adults and immunocompromised populations who haven't built up enough protection from the vaccines.
Nitin Mohan, an epidemiology and public health expert at Western University, agreed, adding that while third doses should "decrease the amount of hospitalizations and deaths we're seeing," the rate of spread with Omicron could make things more difficult to contain.
"We know Omicron is very infectious ... and that's where the modelling numbers are quite drastic," he said.
"What we can expect in the next few weeks is that individuals who are not vaccinated will continue to dominate (numbers of) those getting the virus and ending up in hospitals.
"And even if the disease is more mild, the sheer number of folks who will be getting Omicron infections can easily overwhelm health systems."
This report by The Canadian Press was first published Thursday, Dec. 16, 2021.