Two medical officers of health from neighbouring districts say the timing of the late-spring resurgence of influenza they are witnessing is unprecedented.
"I've never seen anything like this, especially in May," confirms Dr. Jim Chirico of the North Bay Parry Sound District Health Unit.
"Usually we see cases starting in September and maybe peaking in January or thereabouts and then steadily starting to decline with maybe a little bit of an increase in the spring of [Influenza] B," says Chirico. "Now, what we're seeing is the season has shifted and we started seeing cases in March. May has shown the greatest increase, and is steadily increasing."
Confirmed cases of Influenza A in the district have risen sharply — increasing by 11 times — from seven cases on April 30 to 77, as of Thursday.
A similar scenario with even more rapid growth in numbers is playing out in Public Health Sudbury and Districts where Dr. Penny Sutcliffe has taken notice of the recent increase in Influenza A in that district — and across Canada.
Since PHSD reported its first two cases of 2021-22 during the first week of May, confirmed Influenza A cases have increased to 49, as of this week, a more than twenty-fold increase.
According to this Sudbury.com report, the unusually late flu outbreak is something public health has not faced before and it is difficult to predict the outcome. With pandemic precautions lifting, the flu is making a comeback, Sutcliffe says.
Chirico concurs. "We didn't have hardly anything until this spring. In 2019-20, we had 142 confirmed cases among residents in the region. Bear in mind we don't do a lot of mass testing, so the numbers that I'm quoting are far less than what is circulating in the community.
"In 2020-21, there was only one confirmed case, locally. That was with the onset of COVID-19. Now, in the 2021-22 flu season, we've had 77 confirmed [Influenza A] cases. So, again, there are probably a lot more in the community and the vast majority have occurred, certainly, in May and are still on the increase."
According to Public Health Ontario, "The influenza virus or 'flu' is a respiratory virus that circulates in Ontario, most frequently in the fall and winter. Influenza spreads from person to person through coughing, sneezing or having face-to-face contact. It can cause mild to severe respiratory disease. While anyone can get influenza, the very young, the elderly and people with certain medical conditions are at higher risk of complications. The best way to prevent infection is to receive the seasonal influenza vaccine every year."
Sutcliffe says the public health measures related to the COVID-19 pandemic delayed the onset of common respiratory illnesses, including influenza.
Those measures include increased hygiene and public health awareness, such as physical distancing and hand washing. During periods in which movement was restricted or locked down and stay-at-home orders were in place, fewer likely ventured out to get tested when unwell. The lack of international travel also played a role, experts say, as did the reduced interaction of children during the pandemic.
"What the future holds, I really can't say," says Chirico. "We don't know if it's going to continue to increase like this. Usually, this is what the Southern Hemisphere experiences, where their cases come during our summer and we don't see very many. We don't know what's going to happen as we progress through the summer into the fall. We do have influenza vaccine available if required."