Will the COVID-19 vaccine be annual? Can I visit a vaccinated parent? Your questions answered

Canada's COVID-19 vaccine rollout is ramping up, but questions around the process linger.

There are now four vaccines approved for use in Canada, with Johnson & Johnson's single-dose vaccination approved last week by Health Canada. 

The National Advisory Committee on Immunizations (NACI) also recommended delaying second doses of two-dose vaccines up to four months, meaning more Canadians could be vaccinated sooner.

As part of Cross Country Checkup's regular Ask Me Anything series, Health Canada's Chief Medical Advisor Dr. Supriya Sharma answered callers' questions about vaccine eligibility, safety and the future of COVID-19.

Will the COVID-19 be a yearly vaccination?

Jon Sigurdson calling from Langford, B.C., asked if people will need to get a COVID-19 vaccine every year, similar to the way vaccines that protect against the flu are administered.

Each year, the influenza vaccine undergoes something called a strain change, a modification to target specific strains, Sharma explained.

While the coronavirus that causes COVID-19, SARS-CoV-2, mutates like all viruses, it does not mutate as quickly as influenza viruses, she said.

"Right now, the vaccines that we have actually still show good efficacy against the variants — the major variants — for the things that matter the most, so hospitalizations and deaths," said Sharma.

"I don't think we'll get to a place where we'll need a yearly vaccine, but we might be in a place where we have different types of vaccines or boosters."

But Sharma adds that Health Canada is looking ahead in the event the coronavirus mutations are more severe or change more rapidly, and requires a booster shot or a strain change.

"We published guidance for companies, just to let them know what kind of data that we would need to see, because they would need to come back for another authorization and we would make sure that that's done quickly," she said.

Can I visit elderly parents if they're vaccinated, but I'm not?

Marina MacTavish is hopeful her mother, who is in her late 80s, will be vaccinated soon. She asked, "When she has hers done, can I visit her? Or should I hold off until I get mine as well?"

Sharma says that waiting until both parties are vaccinated offers the best level of protection.

"If you have two people that are vaccinated and are also wearing masks, that would be even better," she added.

Though all of the approved vaccines offer a high level of protection, they don't offer 100 per cent protection, Sharma says. That means it's possible someone who is vaccinated could still get and transmit COVID-19.

"We don't want to give people the sense that as soon as you've got your vaccine, you've got this cloak of invincibility and you can never get it," said Sharma.

"They're excellent, but there still is a potential risk."

She notes that people should assess their individual risk tolerance, however. 

"Each situation is a little bit different but we're not at a place, unfortunately, yet that we can say as soon as somebody has got a vaccine, that they can go back ... and do all of those things that they were doing before."

Hear more from Dr. Supriya Sharma and Cross Country Checkup's Ask Me Anything on CBC Listen.