A reversal south of the border
The U.S. Food and Drug Administration has approved Moderna's mRNA flu vaccine for adults aged 50 and older, reversing an earlier refusal to greenlight the shot. It's a significant moment for flu vaccination technology — and one that Canadians should keep an eye on, since Health Canada is currently reviewing the same vaccine for approval here.
Why this matters for Canada
Up until now, most flu shots available in Canada and the U.S. have relied on older technology, growing vaccine viruses in eggs or cell cultures over several months. mRNA vaccines, by contrast, use genetic instructions that teach the body to build its own immune response — the same core technology behind the COVID-19 vaccines from Moderna and Pfizer that millions of Canadians have already received.
Proponents argue mRNA flu vaccines could be manufactured faster and updated more precisely to match circulating strains each season, potentially improving effectiveness compared to traditional flu shots, which vary widely in how well they match the season's dominant strains.
With the FDA's approval now on the books, Health Canada's own review of the Moderna mRNA flu vaccine takes on added weight. Health Canada conducts its own independent scientific assessment before authorizing any vaccine for use in Canada, regardless of what other regulators decide, so approval isn't guaranteed on any particular timeline. Still, a green light from a major regulator like the FDA is often a signal other health agencies watch closely as they conduct their own reviews.
What Canadians can expect
For now, nothing changes immediately for Canadians heading into flu season — traditional flu vaccines remain the standard option available at pharmacies and clinics across the country, including here in Ottawa. But if Health Canada follows the FDA's lead, an mRNA flu shot option could eventually join the annual vaccine lineup, initially aimed at older adults who face higher risks of severe flu complications.
Health officials continue to stress that whichever flu vaccine format is available, getting an annual flu shot remains the most effective way to reduce the risk of severe illness, hospitalization, and complications from influenza — particularly for seniors, young children, and people with underlying health conditions.
Ottawa Public Health typically ramps up flu vaccination clinics each fall, and any update to the vaccines on offer would likely be communicated through the same channels as standard flu shot campaigns.
Source: CBC News
