CHICAGO (WLS) -- Last year's flu season was practically non-existent, but now doctors are bracing for a potential "twindemic" of flu and COVID-19 spikes.
Experts are saying we've built up less natural immunity against influenza because so few people were infected in 2020. Now health officials are urging everyone to get the flu shot if they can.
"If people get their shot, we hopefully will make it a good flu season," said Dr. Juanita Mora, an allergy and immunity specialist.
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Centers for Disease Control and Prevention data show nearly 194 million flu shots were given out last year. That's a 7% increase from 2019.
"A lot of people are not masking or being as rigorous about washing their hands. There's a lot more events going on like concerts and so forth and not enough people getting their flu shots, and this is why we're concerned that the flu season might be a bad one," said Mora.
Mora said the best time to get the flu shot is now. Anyone 6 months and over can get a flu shot.
New research from the University of Arizona shows getting the flu vaccine actually boosts people's innate immune system.
"It allows us to not only fight the flu virus, but it allows us to fight other viruses as well, makes our body stronger, including COVID-19," said Mora.
Dr. Jonathan Pinsky, the medical director of infection control and prevention at Edward Hospital, said it's difficult to differentiate COVID-19 symptoms with those of cold, flu and allergies.
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"It's very important to get tested, and I wouldn't rely on symptoms or guessing; the only way to know is to get tested," said Pinsky.
Pinsky said it's difficult to to know what's going to happen this flu season, so preparation is key.
"If we still continue to mask and do all those mitigation efforts, that will also have a dramatic impact on whether we see a lot of flu this year," he said.
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And Mora said it's okay to prepare for both.
"We can get both the flu shot and the COVID-19 booster all at the same time. It's one visit to your pharmacy, to your doctor, get both shots, get protected," said Mora.