Flu cases in the U.K. are already triple what they were at this time last year. Here Andreas Philippi (l), Lower Saxony's Minister for Social Affairs, Labor, Health and Equality, gives the flu vaccine to Fabian Feil, President of the State Health Office (NLGA) (Photo by Shireen Broszies/picture alliance via Getty Images) dpa/picture alliance via Getty Images

Here’s a new spreading concern. It’s a new strain of the H3N2 influenza virus known as subclade K. And having this subclade K now spreading among people may be far from an OK situation. With surges of flu cases already happening in the U.K., Canada and Japan, the concern is that subclade K may lead to the Northern Hemisphere—which by the way includes the U.S.—having a worse flu season in 2025-2026. This is probably not the type of K

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