Which COVID-19 booster shot should I get? Your questions answered

This story idea came from audience members, like you, who got in touch with us. Send us all of your questions about COVID-19. We are listening: covid@cbc.ca.

As the omicron variant continues to spread, many of you have been writing to us about COVID-19 booster vaccines.

We have been listening and posing your most-common questions to the experts. Here's what they have to say.

That depends on where you live.

Whether or not you will be offered a COVID-19 booster shot is based on each province or territory's eligibility criteria and rollout plan.

Earlier this month, the National Advisory Committee on Immunization (NACI) recommended mRNA booster shots be administered to all Canadians over the age of 50 and anyone who falls into the high-risk category, including health care workers, Indigenous people, residents of long-term care homes or those living in congregate care settings. 

Anyone who received the AstraZeneca or Johnson & Johnson vaccines, at least six months out from the second shot, is also included in NACI's recommendation, which followed one issued in September that recommended boosters for some immunocompromised individuals. 

This announcement came amid debate around eligibility expansion prompted by the new omicron variant. NACI's latest recommendation is giving provinces and territories the scope to widen the currently limited booster shot campaign.

Here's where you can find the eligibility criteria for booster shots in every province and territory as of December 2021:

Right now, you have two options.

Health Canada has authorized Moderna's COVID-19 vaccine (also known as Spikevax) and Pfizer-BioNTech's vaccine (Comirnaty) for booster-shot use in people 18 or older. Both are mRNA vaccines.

The Moderna booster shot is a half dose. The Pfizer-BioNTech booster is a full dose.

So how do you know which one is best for you? According to the experts, it may not matter. 

"We've got randomized trial evidence and real-world evidence that it really doesn't matter what booster you get or your third dose that you get," said Dr. Prabhat Jha, director of the Centre for Global Health Research at St. Michael's Hospital and professor of epidemiology at the University of Toronto.