A nurse administers a COVID-19 vaccine at a mass vaccination clinic in Mississauga, Ont., on Dec. 24.Chris Young/The Canadian Press
Fahad Razak, Arthur Slutsky and David Naylor are professors at the University of Toronto.
The Omicron variant of SARS-CoV-2 arrived at the worst possible time. Cold weather has kept us indoors, creating ideal conditions for airborne spread. The festive season brought more shopping, more social gatherings – and even more spread.
The variant’s impact was therefore immediate. Many Canadians cancelled their holiday plans as case numbers exploded. Now, with the threat of school closings and delayed surgeries looming, it has begun to feel like December of 2020 all over again.
In reality, however, Canadians are in a much different place today. And we should remember that, amid the déjà-vu despair.
In late December, 2020, COVID-19 vaccines were just starting to roll out. Canada’s wise bet on longer intervals between doses not only gave us a head start on population coverage by allowing us to prioritize first doses, but also provided stronger immunity, with good durability.
While two-dose protection against mild illness from Omicron is proving to be much lower than with earlier variants, a third shot appears to boost protection substantially for those who have already received two mRNA vaccines or two AstraZeneca jabs. Protection should be similarly enhanced for Canadians who mixed their first two doses. Two doses of mRNA vaccines also offer strong protection against severe disease from Omicron.
Fortunately, about 87 per cent of Canadians 12 and older have already had two shots, and a steady rollout of vaccines is under way for children aged 5 to 11. Several million adults have already had three shots. Total vaccinations are currently growing by about 400,000 a day, the majority of which are third doses.
Individuals in all age brackets are also testing positive with Omicron but having no or few symptoms, and international evidence suggests that Omicron is associated with milder disease. This may have as much to do with population immunity accruing from vaccines or past COVID-19 infections as any intrinsic weakening of viral virulence.
Treatment has also been transformed since the early days of the pandemic. Today, thanks to researchers who have conducted many large clinical trials at unprecedented speed, there are a number of proven interventions for COVID-19, including passive immunization with an antibody cocktail; antiviral agents and monoclonal antibodies early in infection; steroids, blood thinners and immune-system modulating medications for those with mild to moderate illness; and more effective use of mechanical ventilation. In short, we can now prevent and treat COVID-19 across the full spectrum of disease.
Yes, Canadians still have a fight on our hands. With its staggering infectiousness, Omicron has blown past previous daily case records in multiple provinces. Testing and tracing capacity has already been overrun. And make no mistake: This variant will eventually find those who are unvaccinated or otherwise vulnerable, and these people are especially susceptible to severe disease. This could send large numbers of Canadians to hospital. Coupled with widespread infection of health care workers, Omicron could still overwhelm our health care systems and worsen existing backlogs. Meanwhile, people infected with Omicron can wind up sick at home for a week or more, while countless others will have to isolate after potential exposure.
This variant will not be eliminated by long lockdowns. Instead, each jurisdiction will have to sort out a mitigation strategy based on local epidemiology, patterns of vaccine coverage and health care capacity. Short-term mitigation in turn has one overarching goal: decelerating caseload growth. Slowing spread buys time for more third shots to be given, and will directly and indirectly help ease the burden on our health care facilities. While risks of “long COVID” among infected individuals are still unclear, slower spread and more vaccines may also safeguard countless individuals from troubling postviral syndromes.
Today, some provinces are moving aggressively to slow the spread. Others are gambling recklessly with few restrictions – an approach we saw last summer that is again unlikely to end well.
All that said, this fast-spreading variant may just be the storm before the calm. If indeed Omicron does not take the same per-case toll as Delta, then displacement of Delta could be a net positive. Further, as Omicron spreads in the weeks ahead, those who were infected may be able to repel future variants that share genetic elements with Omicron. Thus, while it is still too early to know, there is a chance that Omicron will hasten the transition of SARS-CoV-2 into an endemic virus – one that flares intermittently, but no longer has the same capacity to disrupt the world.
Whether or not that happy ending occurs, though, one thing is clear: Low-income countries have been left behind. In those countries, only 8 per cent of the population has received even one dose. That must be remedied urgently – not just to help protect the world from future variants such as Omicron, but because it is the moral thing to do.
Keep your Opinions sharp and informed. Get the Opinion newsletter. Sign up today.