The flu season has started early in the U.S., with cases rising two months before influenza season typically begins.
“Flu is here. It’s early for us to see hospitalizations. Historically, we don’t see flu cases in September. We usually see an uptick around Thanksgiving and Christmas. So, this flu season is early,” said Dr. Michelle Barron, UCHealth’s senior medical director of infection prevention and control and one of the top infectious disease experts in Colorado.
She’s urging people to get their flu vaccines as soon as possible.
“Once flu cases start rising, they’ll go up fast. And we don’t want people to be left without protection,” said Barron, who is also a professor at the University of Colorado School of Medicine on the Anschutz Medical Campus.
So far, only a handful of patients have needed hospital care for the influenza virus in the UCHealth system. Around the U.S. cases have spiked in the southwest, with Texas so far logging the highest number of cases. New Mexico is also seeing spikes, as is Georgia.
“The fact that we’re seeing cases at all this early means it’s going to keep circulating more widely in the community,” Barron said.
She and other medical experts had predicted an early flu season for 2022 and early 2023. They also are bracing for much higher influenza activity than in recent years. That’s because Australian health officials saw an early, severe flu season during their fall and winter earlier this year.
North America typically follows the same patterns that emerge in the southern hemisphere.
The COVID-19 pandemic likely is driving higher flu case numbers this year. Back in 2020 and early 2021, before COVID-19 vaccines were widely available, many people were wearing masks and avoiding close contact with others in crowded, indoor spaces.
Those preventive measures drove down both COVID-19 and flu cases, which were almost non-existent two years ago.
Last year’s flu season also was relatively mild. The near absence of flu cases has helped people stay well. At the same time, our bodies don’t have recent immunities to flu, so infections could hit people harder this year.
“Things are off kilter now and will be off kilter for a while,” Barron said.
Most UCHealth patients treated for flu so far have tested positive for Type A influenza, which normally arrives first. There have been some Type B cases as well.
The majority of flu cases so far have emerged among children and teens younger than age 18. That’s not surprising since kids are back in school, Barron said.
It’s typical for flu cases to rise in the fall and winter largely thanks to human behavior.
“People are in school. They’re in close proximity to each other. Temperatures go down. More people are indoors and there are mass gatherings over the holidays,” Barron said.
To avoid getting sick, Barron is encouraging people to get their flu shots and a COVID-19 booster if they’re eligible. It’s safe to get both shots at the same time, and you can even get both doses in the same arm.
Learn more about the new COVID-19 booster shots that specifically fight the newest omicron variants.