CASPER, Wyo. — While the fall and winter are often highlighted by snowfall and holiday gatherings, the season is also marked by the coughing, running noses and chills that come with the flu. This year, health experts warn of an especially virulent flu in Wyoming and beyond.

Data from the Wyoming Department of Health show that Wyoming saw 426 new influenza cases reported in just the final week of 2025, with well over 1,000 cases in total through flu season thus far in Wyoming. The report also states that, through Dec. 27, there had been 19 deaths in Wyoming caused by the flu this season. Nationally, the CDC reports more than 7.5 million cases of the flu and more than 3,100 deaths.

The uptick in flu cases is seen locally, too, the Natrona County Health Department told Oil City News on Thursday.

“While we don’t have exact numbers locally and only have the statewide data that’s reported, I can definitely say anecdotally that locally we’re seeing the same trends that we’re seeing statewide and nationally,” health department PIO Hailey Bloom said. “There is a surge in the rate across our community, the state and the country.”

Bloom said the surge in cases can partially be attributed to this year’s particular strain. The current flu is a mutated strain known as subclade K, originating from the common flu-causing virus influenza A and its variant H3N2. The strain is one of the more aggressive influenza variants, Bloom said.

According to the Centers for Disease Control and Prevention, subclade K is also more adept at resisting immune systems that have already built up protections against other strains of the virus. Bloom also said this season’s vaccine may not be ideally suited for combating the current strain.

“We use the flu season in the southern hemisphere as a predictor [when crafting the vaccine], and we did see that there were some strains not as effectively combated by this year’s flu shot,” she said. “Some years we get a really, really good match on the flu shot and all of the circulating strains are perfect matches to that shot, and some years it’s not as perfect.”

However, Bloom also said some of the increased cases can be attributed to a lower number of people getting vaccinated, which remains the best way to avoid the virus.

Bloom said 989 Natrona County residents have gotten a flu shot through the health department so far this season. That’s down from the 1,227 distributed in the 2024–25 flu season and the 1,478 the year before that.

The decline in vaccinations similarly mirrors a nationwide trend. In mid-December, the CDC reported that roughly 32.5 million flu shots had been given thus far, which is down about 1.9 million from the same point the prior flu season.

People still in need of a vaccine can get one at the Natrona County Health Department by calling ahead and setting up an appointment or by walking in, Bloom said. Vaccinations can also be administered at other locations like various local pharmacies.

Other than getting vaccinated, tips for avoiding the flu include regularly washing hands, avoiding people you know to be sick, exercising caution if feeling under the weather and dressing appropriately for the weather, Bloom said.

“This year’s flu is more aggressive, more intense and not as well covered by the vaccine, so it’s definitely nasty,” Bloom said. “All that said, the flu shot is still going to give significantly more protection than not getting one.”

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