COVID-19 vaccine mandates have worked in Canada — but they're harder to justify than ever

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COVID-19 vaccine mandates have worked extraordinarily well at getting more Canadians vaccinated, but they are increasingly hard to justify — not because of protests or political pressure — but because they're a victim of their own success.

Vaccinations have been mandated for certain jobs, such as health-care workers and federal public servants, while vaccine passports have been put in place for non-essential services such as gyms, bars and restaurants for the general population. 

And they've been an undeniable success: lifting Canada's vaccination rate to one of the highest in the world, protecting vulnerable sectors of society such as hospitals and long-term care and helping us achieve one of the lowest rates of death in the developed world. 

"There's now obvious evidence that they work," Canada's Chief Public Health Officer, Dr. Theresa Tam, said during a press conference Friday. 

"We saw a plateau in the uptake of vaccines after a really tremendous effort by Canadians, and then after the introduction of vaccine mandates by the various provinces and territories and jurisdictions, we did see an uptick."

Health Minister Jean-Yves Duclos added that mandates worked to get 99 per cent of federal public servants vaccinated, and that over the last six months as many as three million Canadians chose to get vaccinated sooner because of them. 

"Vaccination is not punishment. Vaccination is protection," he said. "Let's imagine what the situation with Omicron would now be if we had up to three million Canadians not vaccinated." 

WATCH | Experts say ending vaccine mandates too soon could undo what's been accomplished:

But as the massive Omicron-driven fifth wave subsides across Canada and public health restrictions are set to lift, infectious disease experts and epidemiologists say two-dose mandates are no longer sufficient — and mandating boosters is not a realistic approach. 

That's because while two doses are still effective at preventing severe illness, the highly transmissible Omicron variant has rendered them less protective against infection and transmission to others than with previous coronavirus strains. 

But recent research from Canada and around the world has shown there is substantially more protection against Omicron infection with a third dose — and that boosters are significantly more effective against severe illness than with two doses alone.

A new analysis of vaccine effectiveness in both British Columbia and Quebec, which is set to be released in the coming days as a preprint study, found third doses were about 60 per cent effective against Omicron infection and more than 90 per cent against severe disease. 

"For three doses, we see that the vaccine effectiveness against all outcomes is jacked up," said Dr. Danuta Skowronski, a vaccine effectiveness expert and epidemiology lead at the British Columbia Centre for Disease Control, who co-authored the study.