From the Toronto Star article

The days of the two-shot COVID vaccine regime appear all but over, with countries such as Israel and now the United States opening up widespread access to not just a third shot to bolster waning protection against infection, but a fourth. It’s left some experts wondering whether Canada, which worked hard to get those first two shots into arms, is now falling behind in the push to vaccinate its citizens.

The American Food and Drug Administration this week approved a fourth shot for people 50 and older in the U.S. While at least Pfizer says it has begun conversations with Health Canada, the regulatory body has yet to see an official application for that cohort to get a fourth dose from anyone.

Meanwhile, a sub-variant of highly infectious Omicron has upended what we knew about the virus — again — meaning that, at least for high-risk people, vaccination is looking less like a milestone to be achieved, and more like a process to be maintained.

That’s a message that may not yet have widespread acceptance in Canada, where 85 per cent of people have two doses but just under half have rolled up their sleeves for a third.

“I think people feel like they did their part,” says Dr. Tara Kiran, a family doctor at St. Michael’s Hospital and the Fidani Chair in Improvement and Innovation at the University of Toronto.

“They got their first and second doses, and maybe they were even on the fence, but they were like, ‘I’m going to roll up my sleeves and do it, because it’s important.’”

But when it comes to a third, or even fourth dose, that enthusiasm has tapered off, especially after a concerted push from health-care workers when Omicron landed in December, Kiran said.