When the first round of COVID-19 vaccines arrived in late 2020, millions of unprotected Canadians rushed to get a shot as soon as they could.
Nearly two years later, the updated vaccines, which target the dominant Omicron family of variants, are being rolled out across the country.
And at this time of the pandemic, the immunity picture is much more complicated.
“Now what we have are different people who have been vaccinated at different times, maybe even with different vaccines. Many people have also been infected and recovered from COVID-19 at different points in time,” said Dr. Isaac Bogoch, an infectious disease specialist at the University Health Network in Toronto.
“So it’s much more difficult to have a one-size-fits-all approach to vaccine deployment.”
The timing of your next dose now depends on your level of risk and when you were last vaccinated or infected, with federal guidance suggesting that most Canadian adults should wait up to six months or so earlier of receiving another vaccine, or about three months in situations where the risk of serious illness is greater.
To understand the best approach, CBC News spoke to a list of medical experts, including infectious disease specialists, immunologists and virologists, and reviewed the latest guidance from Canada’s top vaccine advisors.
We’ve broken down their tips into a step-by-step process. You can take the quiz below to see how it applies to you. Or read on to learn the science behind how to schedule your next booster to avoid a COVID infection for as long as possible.