After last year’s unprecedentedly mild flu season, Colorado’s experiencing another quieter-than-usual winter for influenza thanks to COVID-19 mitigation efforts.

As of Thursday, 353 Coloradans have been hospitalized from influenza since the season began in the fall. That’s higher than last year’s entire total by a factor of 10, which saw only 34 hospitalizations for flu. But it’s still far from pre-pandemic levels: By Jan. 27, 2020, for instance, 1,223 residents had been hospitalized with the disease.

Last year was an anomaly, public health officials have said, unprecedented in how few people were hospitalized with flu. It was likely because of high vaccination rates and because of masking, school and business closures, and other pandemic-related efforts. 

Masks have been required in the Denver metro for more than two months, but schools have not had to close and businesses are broadly open for business. That likely explains why flu rates are higher this year, said Heather Roth, the immunization branch chief for the state Department of Public Health and Environment.

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Still, this year is remarkably mild, too. It represents a rare positive for a beleaguered health system, battered for months now by COVID-19, staffing shortages, burnout and sicker-than-usual patients. In the late summer and early fall, public health officials warned that influenza – which regularly sends more than 3,000 Coloradans to the hospital during its October-to-spring season – could add another layer of stress atop the health system. 

Flu vaccinations are lower than last year, when local public health officials pressed inoculation heavily and used the rollout of those jabs as a dry-run for the coming COVID vaccine. But the rates are still high – about 1.8 million doses, which is better than the 2019-20 season, Roth said.

In Denver, 30 people were hospitalized with the flu in December, said Tori Burket, the manager of the Denver Department of Public Health and Environment’s epidemiology and disease intervention program. In past years, that would often swing between 50 and 160. Thirty-four more people have been hospitalized in January with the virus, compared to as many as 200 in years past.

Roth said the true severity – or, as the data indicates, mildness – of this season won’t be fully clear for several more months. 

She said state officials are aware of 14 cases of “flurona” – people who were infected with influenza and COVID-19 simultaneously. Thirteen of them were adults, Roth said. That number has likely gone up, given omicron’s spread and that the flu season is ongoing. 

“We anticipate that number is probably not insignificant,” she said of the true number of residents who have been ill with both diseases at once.

You can get flu and COVID-19 vaccinations at the same time. More information on vaccinations and where to get them can be found on the state health department’s website.