Quebec rolling out new bivalent COVID-19 vaccine against Omicron

Moderna's new bivalent COVID-19 vaccine against Omicron variant BA.1 will become available as of noon Thursday, Quebec's public health director announced.

Quebec already has 800,000 doses of the vaccine, Dr. Luc Boileau shared at a news conference Wednesday afternoon.

"We do not expect that there will be a lack of availability for our population," he said.

Those who had their last vaccine dose more than five months ago and those infected with the virus more than three months ago will be eligible to get a dose.

Children over five and teens as old as 17 will be also be able to get the new vaccine if they're at a higher risk of COVID-19 complications and their physician recommends it.

Health Canada formally approved Moderna's updated COVID-19 vaccine last week for people age 18 and older.

The vaccine is the first in Canada to target both the original virus and the Omicron variant BA.1 that emerged late last year and drove the largest wave of infection and hospitalization among Canadians in the pandemic.

Currently 85 per cent of all Quebecers have received at least their first dose of a COVID-19 vaccine, according to public health data.

Trying to avoid twindemic of flu, COVID

The flu vaccine will also become available this October, instead of its usual roll out in early November. It's being done in the hope of avoiding a resurgence of flu and COVID-19 outbreaks that could threaten to overwhelm hospitals, Boileau said.

International experts have warned of a so-called twindemic with flu season threatening to be very difficult.

Boileau said there are still roughly 3,400 health-care workers off the job right now because they need to isolate. Hospitalizations continue to trend downward, he said, and the hope is it will stay that way.

"We're taking all the care that's needed to be well prepared for that," Boileau said. "We expect it to be something that will ease the capacity of the hospitals."

Clinical trials for the bivalent vaccine have yet to be carried out but studies to date have shown it's 1.6 times more effective than former vaccines in its protection against the BA.1 variant, said Dr. Caroline Quach-Thanh, who sits on Quebec's vaccine committee and spoke alongside Boileau.

Those studies also showed some degree of protection against other Omicron variants, she said.

"Right now it's impossible to say what its effectiveness is in terms of percentage points, we have to do more studies on the ground first," Quach-Thanh said.

While the new shot doesn't directly target dominant Omicron subvariants BA.4 and BA.5, which the U.S. approved an updated shot for this week, Pfizer has submitted an application for Health Canada approval for its BA.4-5 vaccine Friday. Moderna is expected to soon.

With some hoping to wait for that newer vaccine, Quach-Tran urged caution.

"Everybody needs to assess their own risk level. If you're in great health, or have had COVID before, you can probably choose to wait. But if you're over 80 and nearing your fifth month since your last dose, I would urge you not to."

The bivalent vaccine poses a higher risk of myocarditis — inflammation of the heart muscle — for those under 30 than Pfizer does, and for that reason will be prioritized for older adults. Younger Quebecers can still request to receive it however, Quach-Thanh said.

The stock of bivalent vaccines will also gradually replace the stock of past vaccines like Pfizer, Boileau said. He added that's not because the original shot doesn't do its job in preventing severe infection.

While the new shot doesn't directly target dominant Omicron subvariants BA.4 and BA.5, which the U.S. approved an updated shot for this week, Pfizer has submitted an application for Health Canada approval for its BA.4-5 vaccine Friday. Moderna is expected to soon.

Boileau also reminded Quebecers to continue taking measures to reduce the spread of the virus like wearing masks or opting to gather outdoors — even if they're up to date on their boosters.

"Take advantage of the nice weather because the chances of getting infected with COVID-19 is much lower outdoors," he said.