In the third week of 2021, clinical laboratories nationwide tested 23,549 specimens for influenza. Of those, just 0.3 percent (65 tests) turned up positive — a number that is, to put it mildly, absolutely wild.

“Normally, this time of year, we’d be running 20 to 30 percent positive,” said Lynnette Brammer, the head of the Centers for Disease Control and Prevention’s Domestic Influenza Surveillance team.

Although the U.S. continues to struggle with COVID-19, it has apparently beaten the flu into submission. Since the end of September, the combined total of positive flu cases identified by both public health and clinical labs is fewer than 1,500. There are high schools with more people in them. The phenomenon is not only in the United States — worldwide, rates of influenza are nearly off-the-charts low. When you line multiple years up on the same graph, it can even look like there are no cases of flu this year. That’s how out of step we are with the norm.

This massive shift, experts told me, is likely tied to the precautions we’ve taken to avoid catching COVID-19: mask-wearing, social distancing, obsessive cleaning of surfaces (which doesn’t do much to prevent COVID-19 but probably is preventing flu) and even keeping kids out of the classroom. “The major vector for influenza is children,” said David Topham, co-director of the New York Influenza Center of Excellence in Rochester. If they don’t get to breathe on each other like normal, they also can’t transmit as much flu. And that trick still works, even if flu isn’t the reason we’re keeping them distanced.

Read the full article about flu season during COVID-19 by Maggie Koerth at FiveThirtyEight.