Laboratory-confirmed influenza cases in Canada climbed sharply at the end of November, jumping nearly 61 per cent in a single week, according to new federal surveillance data released Friday.
The latest FluWatch+ report shows confirmed flu cases rose from 2,273 to 3,655 during the final week of November. Test positivity also climbed significantly, with 13 per cent of laboratory tests returning positive results compared to 8.5 per cent the week prior—an indication that flu transmission is accelerating as winter approaches.
The surveillance report also tracks COVID-19 and RSV activity, offering a broader look at the spread of respiratory viruses across the country.
Dr. Isaac Bogoch, an infectious disease specialist with the University of Toronto, said the rise in influenza cases could point to a tougher flu season but still falls within what experts consider normal variability. “Influenza kills about 450,000 people per year on the planet,” he said. “It’s especially severe in older Canadians and the youngest Canadians, pregnant women and people who are immunocompromised, but even healthy young people can get absolutely walloped by the flu.”
Bogoch urged Canadians to get vaccinated, noting that most people hospitalized with the flu have not received their shot. “The vaccine this year is not perfect, but it’s still the best we have, and it reduces the risk of the flu,” he said.
FluWatch+ also recorded 1,286 hospitalizations from respiratory illnesses during the same week—an increase of 269 cases, or roughly 26 per cent, from the previous week.
Three major flu strains are circulating this year: H3N2, H1N1 and influenza B. Bogoch emphasized that the seasonal vaccine offers protection against all three. “Of course, the vaccine is still going to have some protection, just not as much as we would like,” he said. “But it has components to protect against all three.”