Where Did The Flu Go? Homebound Kids Shape A Mild Season

This past summer, public health officials sounded warnings about the dangers of an impending flu epidemic on top of the coronavirus pandemic.

Yet this year's flu season has been exceptionally mild.

During the 2019-2020 flu season, some 400,000 people were hospitalized for the flu, with 22,000 deaths, according to the Centers for Disease Control and Prevention. Last week — just ahead of the season's usual peak — the CDC had recorded just 165 flu-related hospitalizations since October.

"Flu has been essentially nonexistent," Dr. William Schaffner, infectious disease specialist at Vanderbilt University, said in an interview with Weekend Edition.

The mild season has benefitted from measures like masks and social distancing, he said. It helps too that, last year, a record number of people got a flu shot.

But Schaffner says there's more to it: Kids — habitual superspreaders — are staying home.

"Children are generally thought of as having the distribution franchise for the influenza virus," Schaffner said. "They produce much more virus, they shed more virus for longer periods of time."

But over the course of the coronavirus pandemic, as schools went virtual and children interacted less, the chances of spreading the flu narrowed.

For Schaffner, the result highlights a distinction in the nature of transmission among the respiratory viruses.

"COVID can be transmitted very readily among adults — very contagious — but flu, I think, really needs children to spread it around amongst themselves and then seed, if you will, the adults in their home and their neighbors," he said.

Since so many dodged the flu this season, Schaffner warns that the virus could hit people harder than normal this fall — when health professionals predict the country will get closer to normalcy.

"Many of us didn't get a boost from encountering the flu virus this year, and so we haven't had a chance to build up our antibodies," he said. "All the more important to get vaccinated this fall."

Samantha Balaban, Ed McNulty and Martha Ann Overland produced and edited the audio version of this story.

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