Dr. Susan Detmer, a veterinary pathologist with the Western College of Veterinary Medicine encouraged the public, especially those who work with pigs, to get the annual flu shot. 
Restrictions imposed in 2020 to slow the spread of COVID also slowed the transmission of influenza. 
“We saw much less of the pandemic strain of H1N1 which circulated among humans in pigs, but lifting restrictions resumed people transmitting the infection to pigs. So I’m hoping that everyone eligible will go out and get their vaccine, whether or not they work with pigs.” 
But it is crucial for people working with pigs to get that vaccine to keep that pandemic H1N1 virus from going back and forth between pigs.  
There is such a low level of circulation of everything in humans, it is quite possible to have another very low season of influenza but all of that can change. 
With the Delta variant of the pandemic virus circulating, more restrictions and less movement of people, less circulation of COVID means less circulation of influenza. Yet people get out and travel and interact in these social events. 
All of that plays into potential modelling for an increase in influenza over the next year. 
“We expect more circulation of influenza in people this year because people move around more but will depend on how much people interact in social situations and at work.” 
Dr. Detmer said circulating in Canada and the United States last year a third influenza B virus. “Influenza B viruses we don’t see in pigs, we can detect antibodies occasionally in pigs for influenza B, but this is not a pig virus in the direct sense. The influenza A viruses which we do see in pigs have split almost half H3N2 at the pandemic H1N1 virus.” 
And thanks to the limited spread of these viruses last year, it limited the genetic variation of these viruses. And most of those are holdovers from the pre-COVID pandemic time.  
Each year, the WHO has a group of influenza experts that usually meet in February to pick out viruses based on what is circulating, including the data collected on the antigenic responses that would help detect the best vaccine viruses among what’s circulating in humans. And they picked an H3N2, a pandemic H1N1, and two different influenza B viruses. The CDC is the U.S. does their analysis participating in the WHO group. They found a slightly different H3N2 that was dominant in North America, as well as a somewhat different pandemic H1N1. So, they picked two other viruses from the WHO selection, and they have the same influenza B strains that the WHO picked. 
She reiterated that in 2020 not a typical human influenza year meant not a normal spread of viruses in pigs with almost as many virus detections in pigs. The normal pattern in Western Canada is a third H1N1, a third H3N2, and a third of the alpha H1N2 viruses. This last year in 2020, H1N2 dominated.  
“The concern is two detections of those in humans, this last flu season. And so far, this flu season, we see mostly the alpha H1N2 and H3N2 viruses in pigs. So it will all depend on how much human to pig transmission we start to see, whether we go back to our normal third, a third, a third split in the pig population.” 
Dr. Detmer said the flu shot would protect people from serious infections and help break the cycle of human to pig to human transmission of the pandemic H1N1 strain.•
— By Harry Siemens