Subclade K has become the dominant form of flu and is slightly different from the virus targeted by this year’s flu vaccine.

A variant of influenza A, H3N2, is spreading across the U.S., with low vaccination rates contributing to infection rates.

The latest variant of the flu strain, medical providers said, can cause symptoms in vulnerable populations including older ...

A new form of the flu, which is highly contagious and aggressive, is sweeping the nation this season. A mutation of influenza ...

A North Alabama emergency doctor thinks the H2N2 subclade k variant is driving the surge in flu cases in North Alabama, and ...

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. That variant, known as “subclade K,” led to early outbreaks in ...

As the end of the year approaches, health authorities are keeping a close watch on a new dominant flu strain circulating ...

There are some unusual symptoms being reported with a new and mutated flu variant quickly spreading in the U.S. ahead of ...

Current data from the CDC suggests the H3N2 strain and subvariant K — the dominant subvariant in the U.S. — are more ...

Changes in the key antigenic regions of H3N2 viruses suggest that the upcoming flu season may require closer attention to ...

The variant emerged after the 2025-2026 flu vaccine was developed, meaning the current vaccine does not target this specific ...

Much of the concern this flu season is coming from the spread of subclade K, a subtype of influenza A. Similar subtypes have ...