COVID-19 infections are on the rise and omicron could quadruple daily case counts, federal modelling says

New modelling released today by the Public Health Agency of Canada (PHAC) suggests the number of COVID-19 cases could increase sharply in the coming weeks as the country grapples with another wave of delta infections and the highly transmissible omicron variant.

While there is a lot of uncertainty about how many cases might be reported, an increase from the current level of over 3,300 cases a day is likely, PHAC said, because Canada is experiencing a "gradual but steady increase" in infections.

The national "rT" — the metric that tracks the average number of people one infected person subsequently will infect — is now over one. That means the pandemic is again in growth mode.

Pointing to early findings from South Africa, where omicron was first identified and case counts have skyrocketed, PHAC said cases could quadruple to 12,000 a day in January if "omicron successfully establishes" and the current levels of transmission are maintained.

Omicron's "greater transmissibility" and the potential for "reduced protection from prior infection/vaccination" could drive this resurgence, PHAC said. The effectiveness of the current slate of COVID-19 vaccines against omicron is still under review.

As of December 9, there have been 87 confirmed cases of omicron reported in seven Canadian jurisdictions. To date, all reported cases of omicron in Canada have been asymptomatic or mild.

Even without omicron circulating widely, PHAC modelling suggests Canada could still be dealing with another wave of delta cases in the new year.

If the current level of transmission is maintained, cases stand to double to between 6,000 and 7,000 a day in January. If transmission levels increase, a delta-driven wave of roughly 12,000 cases a day is also possible, PHAC said.

While the modelling is concerning, Dr. Howard Njoo, Canada's deputy chief public health officer, said people shouldn't go into "panic mode."

"We should all respect the virus. It's a formidable foe and it's obviously evolving as we fight against it," he said.

"We need to respect it but not be panicked or scared. We have a great number of tools now and we know a lot more about the virus. We know vaccines protect against serious illness."

New outbreaks reported in schools

Canadians between the ages of 5 and 11 are the most likely to contract COVID-19 right now given the low vaccine coverage in this demographic. The infection rate among kids aged 5 to 11 is over 20 cases per 100,000 people — four times higher than the rate for any other age group.

Hundreds of new COVID outbreaks have been reported in the nation's schools and child care centres in recent weeks, driving up the infection rate for kids under 12.

COVID-19 cases in children often do not involve severe illness. To date, PHAC said, there have been over 380,000 reported cases in children and youths up to 19 years of age, with less than one per cent involving severe illness.

PHAC said the best way to blunt the spread of the virus is to ramp up the immunization campaign for people 5 to 11 and roll out third doses for other age groups.

PHAC data demonstrate just how effective the COVID-19 shots have been at keeping people out of the hospital. Unvaccinated people between the ages of 12 and 59 were 32 times more likely to be hospitalized for the virus than those who have had two doses.

Unvaccinated people over the age of 60 are 16 times more likely to end up in the hospital than the fully vaccinated. That's a positive sign, since older adults are more likely to produce a less robust response to vaccinations.

Last week, the National Advisory Committee on Immunization (NACI) strongly recommended all Canadians over 50 and other vulnerable groups — such as health care workers, Indigenous people and those living in congregate care settings — get a booster shot six months after their second dose. It is also recommending that people aged 18-49 also get that third dose when they're eligible.

Modelling suggests hospital capacity can be kept at manageable levels if booster shots are widely available and Canadian kids get their shots. If the booster shot campaign or the rollout of vaccinations for kids 5 to 11 slows down, it's likely the nation's hospitals will be overrun in the new year, PHAC said.

"While there is still considerable uncertainty regarding the potential for omicron to evade immunity and increase severity, rapid resurgence in cases could potentially strain our still fragile health care system," said Dr. Theresa Tam, Canada's chief public health officer.

"Heeding public health advice, completing our primary series of COVID-19 vaccines, getting a booster dose when eligible and keeping up with basic personal precautions — like wearing a well-fitted, well-constructed face mask, avoiding crowding, and improving ventilation and other layers of protection — continue to be our best and safest way forward."

Tam said Canadians can gather safely for Christmas if they restrict their guest list to people who are fully vaccinated. She also recommended keeping gatherings small.

"As we look to the holidays and weeks ahead, caution is still warranted. But as you consider the risks for you and yours, we can be thankful we're better protected with vaccines," Tam said.

Health minister warns of 'delays' and 'hassle' for travellers

Health Minister Jean-Yves Duclos said the federal government is focused on travel measures to keep omicron cases out of Canada.

After a slow start, the federal government is now administering 17,000 arrival tests a day at the country's airports, Duclos said, a measure meant to catch returning COVID-19 cases before they can infect others.

All foreign travellers from non-U.S. destinations can expect to be subjected to a test on arrival at a Canadian airport, he said. This new test is in addition to the pre-departure molecular test that all travellers must undergo before leaving for Canada.

"Canadians who are thinking of travelling abroad need to be warned that the situation abroad is both risky and unstable. They should also know that returning to Canada will likely involve delays and hassle," Duclos said.

Duclos said travellers need to plan ahead, prepare for a much longer airport arrivals experience, put together a strong quarantine plan and use the ArriveCAN application to submit the required information.