Omicron variant caseload expected to 'rapidly escalate' in the coming days, Tam says

Canada's chief public health officer said today there is evidence of community spread of the highly transmissible omicron variant and new COVID-19 cases are expected to "rapidly escalate" in the coming days.

Dr. Theresa Tam said there is "great spread potential" with omicron and the situation in Canada is a "few days or maybe a week" behind the U.K. — where British Prime Minister Boris Johnson today said that the country is dealing with a "tidal wave" of new infections, with the caseload doubling every two or three days as the variant takes hold.

"We know how to work together to flatten that curve and we need to do that pretty rapidly, starting now," Tam said. "As with other waves of the pandemic, rapid action and reducing contact [are] key to preventing that very sharp peak."

In Ontario, COVID-19 cases have doubled in two weeks' time, with 1,328 new cases reported today. Some communities — notably Kingston, Ont. — have seen conditions rapidly deteriorate with hundreds of new cases posted over the weekend, pushing case counts to the highest level seen since the onset of the pandemic in March 2020.

The Ontario COVID-19 science advisory table said today the omicron variant will replace the currently dominant delta variant as the main strain in the province by Christmas — something Tam said she expects to see happen elsewhere in the country by year's end. Early data suggest omicron is three times more transmissible than delta.

"What we're seeing in Ontario, I expect to be seen in other areas of the country," Tam told a press conference. "We are seeing community transmission, possibly in its early stages, but this can rapidly escalate in the days to come."

While Canada could soon be facing the largest wave of COVID-19 cases ever recorded during this health crisis, one big unknown is just how virulent the omicron variant is compared to past variants like alpha or delta.

WATCH: Tam says there is community transmission of the omicron variant in Canada

The U.K. has reported a stunning 54,661 coronavirus infections in the past 24 hours, but only 10 people with the omicron variant have so far been hospitalized in England.

While researchers scramble to determine the severity of this variant, Tam said provinces must urgently roll out booster shots to protect older and vulnerable Canadians.

She said there's evidence of "waning immunity" from COVID-19 infections and vaccines — and quickly administering a third shot to as many people as possible can help blunt the spread.

Tam also said it will take time for the booster shots to kick in — so Canadians should closely follow public health guidelines and "layer on protections" such as medical-grade masks until more people are covered with a third shot.

"We've achieved high vaccination coverage compared to other countries and here we are again asking people to roll up their sleeves for those booster shots — especially for the higher risk populations. That's what we need to focus on," Tam said.

"But you need both vaccines and reduced contact rates right to dampen the effect of this virus," she said.