Montreal

Some Quebecers should get periodic COVID-19 boosters, province's vaccine committee says

The goal would be to offer vaccines during “periodic immunity boosting campaigns,” rather than focusing on how many times someone has received a shot.

Strategy to shift to 'periodic immunity boosting campaigns' for the most vulnerable

Vulnerable populations should get periodic COVID-19 boosters to keep their immunity to the virus high, the Quebec immunization committee suggests. (Ivanoh Demers/Radio-Canada)

Quebec's immunization committee is recommending that some people get a third booster shot as early as the end of the summer.

The committee, also known as the CIQ, released its new COVID-19 recommendations Monday. 

It suggests that more vulnerable populations — including those over the age of 60, those with underlying conditions, pregnant women and health-care workers — get additional doses of a COVID-19 vaccine going forward, even if they've already received two boosters.

The goal would be to offer vaccines during "periodic immunity boosting campaigns," rather than focusing on how many times someone has received a shot.

For those who do not fall into the groups above, two baseline doses and one booster will be considered sufficiently vaccinated. The periodic boosters will not be made available to those who don't qualify.

The basic vaccination campaign — two doses and a booster — will remain available to all Quebecers for the foreseeable future.

The CIQ notes that the recommendations are subject to change, as there are still "uncertainties regarding the evolution [of the virus] over the coming months." 

Adjusting vaccine formula may help

Université du Québec à Montréal virologist Dr. Benoît Barbeau says it's impossible to know exactly what is going to happen in the fall or winter, but just like with any respiratory viruses, there will likely be an increase in cases.

Barbeau said there are efforts to maximize the vaccine's effectiveness against variants. 

For now, administering the vaccine to the most vulnerable is an important step, he said, but should the vaccines become better adapted to circulating variants like Omicron, it might become time to offer another dose of the vaccine to the rest of the population, as is done with the flu shot each fall.

"That's what the companies are doing as much as possible, aiming at diversifying the content of your vaccine and therefore making it more adapted," Barbeau said.

"And I think that's definitely one of the important trajectories that the vaccine strategy should take right now. And that's what they're doing, actually."

Booster shots needed for everybody, expert says

However, initial trial data on a vaccine that targets Omicron, for example, have not been promising, said McMaster University Prof. Dawn Bowdish, Canada Research Chair in aging and immunity. 

"The chance of it being approved and being rolled out before this wave really takes hold becomes less likely every day, and I do hope I am wrong about that," said Bowdish. 

The effectiveness of vaccines begins to wane within about six months for most people, and sooner for the more vulnerable groups, such as older people or those with compromised immune systems, she said.

Dawn Bowdish
Prof. Dawn Bowdish, an immunologist at McMaster University in Hamilton, Ont., said initial trial data on a vaccine that targets Omicron have not been very promising. (Marcy Cuttler/CBC)

Ideally, everybody would be getting vaccinated before the next wave gains steam, said Bowdish.

She is among those waiting with bated breath for her second booster shot, but decision makers aren't taking that step just yet as they are faced with he financial and logistical burden of rolling out another vaccine campaign, she explained.

It's important to vaccinate everyone at the start of a wave, rather than in a "haphazard way," she said.

"The data is pretty unequivocal: those of us who are six months out from our last dose are getting to the point where we need to start worrying about what may happen when we're infected."