An interim analysis published in Eurosurveillance estimates that the COVID-19 vaccine for the 2025/26 season reduced the risk of illness in Canada by about half at about 9 weeks after vaccination, offering protection beyond the vaccine’s target strain.

Seasonal COVID-19 vaccination is recommended in Canada as in several other countries for people older than 6 months with an increased risk of severe illness from the infection, and for all adults aged 65 or older. In the 2025/26 respiratory virus season, the vaccine was updated to target the LP.8.1 strain as recommended by the World Health Organization (WHO), but other strains were also circulating during that period.