Chicago-area doctors worry over subclade K flu strain ahead of Thanksgiving 2025 holiday

ELMHURST, Ill. (WLS) — Many have gotten their flu shots. But some doctors are concerned about a new strain of the flu called subclade K that is resistant to the vaccine just before people get together for the holidays.
As families gather for the big Thanksgiving feast, sharing a meal, conversation and possibly airborne germs could help spread the flu virus more rapidly. Last year’s flu season was especially harsh, and some experts are predicting it could be the same or worse this season.
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“Last year, just after Thanksgiving, we went from seeing no patients to everyone and their grandma had the flu,” said Dr. Kevin Emmerich, with Endeavor Health Elmhurst Hospital.
This year, the subclade K strain of the flu has already caused severe outbreaks in other countries, including Canada, the UK and Japan, where it was declared an epidemic.
Doctors say other countries are generally a good predictor of what can be expected in this country. And it’s not pleasant.
“The flu can feel like a car hit you. Your body hurts. You could need hospitalization or ICU,” said Dr. Shivanjali Shankaran, with Rush.
Doctors say young children and older adults are especially at risk. And while doctors say the flu vaccine in the U.S. can help protect against more severe symptoms, only about one in five people in Chicago have been vaccinated.
“It does offer some protection, especially to people who are high-risk. So kids under 6 months and adults over 65 and people with cancer, transplants,” Emmerich said.
Experts say flu activity remains low in the U.S. so far, but it’s on the rise. So they recommend protecting yourself.
“Try to wear a mask, very helpful in preventing the viruses. Hand-washing, we always underestimate the importance of that,” Shankaran said.
It’s too soon to predict the flu season in the U.S., but experts say it’s more difficult because the Centers for Disease Control and Prevention was unable to track flu activity during the 44-day government shutdown.
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