The K variant causes more intense flu symptoms, including fever, chills, headache, fatigue, cough, sore throat and runny nose, according to experts. FILE - It's not clear whether this year's flu vaccine directly addresses this specific mutation, but people are still urged to get a flu shot. Subclade K is the "perfect storm" for an aggressive flu season, Maniar suggested, as vaccination rates overall are down, and it's uncertain whether this year's flu vaccine directly addresses this specific mutation. "We're going in [to this flu season] with lower vaccination rates and a variant that in itself seems to be more aggressive." Maniar stressed that it's not too late to get the flu vaccine, as peak flu season has not yet arrived.

Source: Fox News December 26, 2025 04:01 UTC