'Tis the SEASON

HOW THE PANDEMIC HAS AFFECTED THE TRANSMISSION OF FLU — AND WHY THIS IS NOT THE YEAR TO BLOW OFF YOUR ANNUAL FLU SHOT

- BRIAN OWENS

A FUNNY THING HAPPENED last year just as the COVID-19 pandemic began sweeping across the world — the flu disappeared. What had been a fairly serious flu season in the northern hemisphere ended abruptly, while the southern hemisphere season, which usually ramps up as the northern one winds down, never really got going.

“We saw flu essentially go away in our surveillance network,” says Dr. Melissa Andrew, a geriatrician and flu researcher at Dalhousie University in Halifax. “And that was true across Canada and around the world.” It’s not a coincidence — right around that time is when we started taking precautions that we know are effective against infectious diseases such as the flu: washing our hands, wearing masks, keeping our distance from other people in public and spending a lot of time alone or with just our immediate families.

“Flu is a respiratory pathogen that is transmitted in many of the same ways as COVID-19, so the public health measures to reduce the transmission of COVID-19 played a role in reducing the rate of influenza transmission as well,” says Dr. Matthew Miller, a virologist at McMaster University in Hamilton, Ont.

As those public health measures have continued while the pandemic drags on, so too have their effects on the flu. In fact, the 2020-21 flu season essentially never happened, according to the Public Health Agency of Canada. “To date this season, there has been no evidence of community circulation of influenza despite continued testing above seasonal levels. Influenza activity has remained below the threshold required to declare the start of the 2020-21 influenza season,” the agency told Canadian Geographic in April 2021 — a month that would usually mark the beginning of the end of the flu season in a normal year.