A new flu strain is quickly spreading. How to stay healthy.
Dec 17, 2025 · Known as subclade K, a new, mutated flu strain that has dominated in Europe and Asia is now rapidly spreading across the US.
"Super flu" surge: What to know about the "Super K" variant
12 hours ago · The United States is seeing a massive surge in flu cases this winter, many of them attributed to the so-called "super flu." Why it matters: An unprecedented rise in flu cases …
Flu Is Rising Rapidly, Driven by a New Variant. Here's What to Know
7 hours ago · WASHINGTON (AP) — Flu is rising rapidly across the U.S., driven by a new variant of the virus — and cases are expected to keep growing with holiday travel.
New Variant Raises Concerns of Another Bad Flu Season
Dec 17, 2025 · The main version of flu spreading in the United States right now is H3N2 subclade K. H3N2 is a common strain, but the specific type of it circulating now — subclade K — is …
Harsh Flu Season May Be Driven by New Variant K
Dec 16, 2025 · This year’s flu season is shaping up to be a nasty one—driven by a new variant of the influenza virus that may be able to slip past our vaccine defenses.
New, Severe Flu Variant Spreading in US: Watch for These …
1 day ago · A mutated strain of influenza A, H3N2 subclade K, is surging worldwide, sparking concern about a severe flu season in the U.S. Here's what to symptoms to look out for.
Flu season in the US is heating up, driven by new subclade K …
Dec 13, 2025 · The majority of flu viruses collected and analyzed by American laboratories during this respiratory virus season have been subclade K, a variant of a flu strain called H3N2, which …
Everything you need to know about ‘subclade K’ flu - and vaccine ...
Nov 14, 2025 · What is H3N2 subclade K influenza? Influenza viruses are constantly evolving, which is why the World Health Organization closely monitors which flu viruses have been …
What Is Subclade K, the New Flu Strain Doctors Call ‘Severe’
Nov 20, 2025 · Infectious disease doctors explain what you need to know about the new flu variant, subclade K, along with how to protect yourself this cold and flu season.
Flu Is Beginning to Hit the U.S. Hard Driven by Influenza A Variant ...
Dec 22, 2025 · At least 14 states and Washington, DC, are seeing high and very high levels of flu, mainly caused by a surprise new influenza mutation called subclade K.