Advertisement

Will we need a new COVID-19 vaccine every few years? Here’s what we know

Click to play video 'Coronavirus: Health official discusses need for seasonal COVID-19 vaccine amid virus variations' Coronavirus: Health official discusses need for seasonal COVID-19 vaccine amid virus variations
Coronavirus: Health official discusses the potential need for a booster shot for the COVID-19 vaccine amid future virus variations – Dec 23, 2020

It looks like Canadians won’t need an annual jab to keep up protections from the coronavirus, Health Canada says, but it’s still possible that booster shots will be required every couple of years to keep our bodies in full fighting form.

Read more: Canada approves Moderna coronavirus vaccine, 1st doses to arrive in ‘coming days’

Studies are currently underway to determine how frequently, if at all, these repeat injections will need to take place.

“We’ve got very, very stable viruses like the measles virus that doesn’t change very often at all. [Then] we have viruses like the influenza virus that we know changes very frequently and you have to get vaccines every year,” explained Dr. Supriya Sharma, chief medical advisor with the regulatory branch of Health Canada, at a Wednesday press conference.
Story continues below advertisement

“This group of viruses is somewhere in between. So at this point in time, I think we’re still looking for evidence.”

Click to play video 'Coronavirus: Canada to receive up to 168,000 doses of Moderna’s COVID-19 vaccine before year’s end' Coronavirus: Canada to receive up to 168,000 doses of Moderna’s COVID-19 vaccine before year’s end
Coronavirus: Canada to receive up to 168,000 doses of Moderna’s COVID-19 vaccine before year’s end – Dec 23, 2020

She said that the early evidence seems to indicate that COVID-19 isn’t as good at mutating itself as influenza – which means it’s extremely unlikely we’d need an annual jab. However, so far, it doesn’t seem to be as stable as the measles virus. That means booster shots might be needed – but, Sharma warned, it’s “a bit early to tell.”

If researchers do find a booster shot is needed, they’d also have to determine how often they’re required – whether it’s every two years, three years, or beyond.

“This is all the types of information that we’re going to be continuing to collect, working internationally to collect that information and monitoring not only the virus, but obviously these vaccines and how we move forward,” Sharma said.

Story continues below advertisement
Click to play video 'Coronavirus: Moderna’s vaccine approval ‘critical’ for equitable access, Health Canada officials say' Coronavirus: Moderna’s vaccine approval ‘critical’ for equitable access, Health Canada officials say
Coronavirus: Moderna’s vaccine approval ‘critical’ for equitable access, Health Canada officials say – Dec 23, 2020

Her comments come on the heels of the news that Canada has approved a second coronavirus vaccine for use in our country, with doses expected to roll out in the coming days. This vaccine, from Moderna, is about 94 per cent effective and doesn’t have the ultra-cold storage requirements as the Pfizer vaccine, making its rollout process easier.

Read more: Canada begins coronavirus vaccine rollout. Here are the provinces’ plans

Prime Minister Justin Trudeau has said doses of the Moderna vaccine will begin to arrive within 48 hours of this approval – and Canada inked a deal that should see up to 168,000 Moderna vaccine doses arriving before the end of the month.

[ Sign up for our Health IQ newsletter for the latest coronavirus updates ]

Trudeau also announced in his Wednesday press conference that Canada will be getting an additional quarter of a million doses of the Pfizer vaccine next month, bringing the total to 750,000 Pfizer vaccine doses for January.

Story continues below advertisement
Click to play video 'Coronavirus: First shipment of Moderna vaccine doses arriving in coming days, Trudeau says' Coronavirus: First shipment of Moderna vaccine doses arriving in coming days, Trudeau says
Coronavirus: First shipment of Moderna vaccine doses arriving in coming days, Trudeau says – Dec 23, 2020

While Canada has signed purchase agreements with multiple vaccine manufacturers, the agreements with Moderna and Pfizer alone should see 60 million doses arrive in Canada by September.

That’s enough to vaccinate 30 million Canadians, just eight million shy of the entire population.

Meanwhile, in addition to questions about the long-term effectiveness of vaccines, there have also been concerns about whether the jabs will continue to be effective against the already-emerging mutations of the vaccine – some of which have prompted Canada to implement a temporary ban on flights from the U.K., where the new faster-spreading virus variant is circulating.

Read more: Canada extends U.K. flight ban 2 more weeks amid COVID-19 mutations

The WHO confirmed on Monday that the mutation is unlikely to impact the effectiveness of existing COVID-19 vaccines, and variants cropping up don’t necessarily mean the virus is getting more dangerous.

Story continues below advertisement

“Often, if you’re changing one thing, you’re losing another,” Dr. Zain Chagla said of virus variants in an interview Monday with Global News.

“And so a virus that could be a bit more reticent to deal with the vaccine, may lose the ability to replicate as well or transmit as well. So, again, these things all have biologic costs…every genetic change is a balance between (the virus) becoming more fit and what it has to give up to become more fit in that sense.”

Click to play video 'Coronavirus: Canada to receive an additional 250,000 Pfizer vaccine doses in January' Coronavirus: Canada to receive an additional 250,000 Pfizer vaccine doses in January
Coronavirus: Canada to receive an additional 250,000 Pfizer vaccine doses in January – Dec 23, 2020

This means that even if the virus changes, the vaccine should remain effective. Sharma added that changes to approved vaccines would require new information to be submitted to Health Canada for study – though the extent of the new information required depends on the significance of the change.

“It depends on how significant that change is. If it’s not a completely new vaccine, then they can actually submit data. And there’s an…abbreviated sort of process,” she said.

Story continues below advertisement

“If there is a significant change to the vaccine, they would have to come back and submit that data to Health Canada. We would review that and then make any changes. If it is a brand new vaccine, completely different, they would have to come in with a full new package of data.”

Read more: Masks, handwashing and distancing remain key amid new U.K. coronavirus variant, doctors say

Meanwhile, as scientists strive to answer the questions about the long-term effectiveness of vaccines against variants of the virus and begin the process of vaccine rollout, Canadians already have some tools at their disposal that can help to control the spread of COVID-19.

Speaking on Wednesday, Trudeau reminded Canadians of these tools.

“This is the time to continue wearing a mask, to keep your distance, to avoid gatherings, and to download and use the COVID Alert app,” he said.

“In other words, please continue to protect those around you.”

Sponsored content