Although a particularly rough 2025/26 influenza season is expected to last for another month or so, cases are well down from their seasonal peak in December
It has been a particularly wide-reaching influenza season, with 572 cases reported by Public Health Sudbury and Districts as of last week.
This, compared to 229 during the entire 2024/25 influenza season (roughly November to April).
“The local case activity has been tapering out since late January,” Dr. Chidubem Okechukwu told Sudbury.com, adding that they’re down to averaging only one to four per week.
The season is typically from November to April, she said, “so the season is not over,” meaning those who are ill shouldn’t be out in public and people should still maintain their vaccinations.
Sudbury.com connected with both Okechukwu and Public Health Sudbury & Districts medical officer of health Dr. Mustafa Hirj for the latest on this year’s influenza season.
This, after a recent spike in norovirus cases spurred Public Health to remind people of the importance of washing their hands.
“Typically what we see in an influenza season is two waves of influenza, because there are two types of influenza,” Hirji said. “Influenza A usually comes first, and then we usually have a smaller influenza B wave in the early spring, so we’ve largely had that influenza A wave, but that B wave is yet to come.”
Medical Officer of Health Dr. Mustafa Hirji,, Public Health Sudbury & Districts. Tyler Clarke / Sudbury.com
This year’s spike in influenza is likely due to two key reasons, Hirji said, including an early-season onset and a pre-Christmas peak.
“There wasn’t enough time for people to get the vaccine before the flu virus started to circulate, so that meant probably not as many people were vaccinated before the flu hit which meant more people were vulnerable,” he said.
As for the pre-Christmas peak in cases, he said, “That’s right when people are at holiday parties, we have a whole bunch of people meeting and mixing right when the flu virus is getting at its peak, and so that probably meant more flu was spreading out at that time because people were having more social interaction.”
Although some credence might be lent to the fact this year’s vaccine effectiveness was only 40 per cent, Hirji contends that although it’s one of many factors that influence how effective a vaccine, “it’s not a perfect correlation.”
The following influenza season’s vaccinations are selected in February, which Hirji said can contribute to some of the mismatch, wherein flu strains end up differing from those selected for the annual vaccine.
However, due to the way viruses work, Hirji said the severity of some years’ influenza outbreaks are actually lessened by poorly-matched vaccines.
Further to that point, he said annual vaccine matches range from near zero per cent to around 60 per cent on the high end.
“Forty per cent is probably average or above-average, despite that mismatch,” he said, adding that this season’s vaccine “is still pretty good.”
Plus, Okechukwu said, even in cases where vaccines don’t match well, “it’s still effective to reduce the severity of illness, lower the risk of hospitalization and protect those who are most vulnerable, like young people, people who are pregnant and older adults.”
Vaccine hesitancy might also be a contributing factor, Okechukwu, clarifying that Ontario doesn’t maintain a reliable tracking system between all vaccine providers so there’s no hard data to draw from, but that it has been a broader trend.
Public Health Sudbury and Districts’ latest respiratory illness updates cites nine new people in hospital due to respiratory illness, including three with COVID-19, two with influenza and four with RSV (respiratory syncytial virus).
The Public Health Sudbury and Districts website notes that everyone over six months of age should get a flu shot each year. Vaccinations are available from health-care providers, walk-in clinics, public health units and more than 50 local pharmacies every year, usually by late October or early November.
Tyler Clarke covers city hall and political affairs for Sudbury.com.