The spread of influenza became more severe this fall, particularly in the United States and the United Kingdom. The US Centers for Disease Control and Prevention has designated the 2024-25 flu season as the most severe season since 2017-18. In the UK, the spread has begun earlier than at any time since 2003-04.
Against this backdrop, some media outlets have begun using the term “super flu.” However, this term is not an official medical term. The actual name is “subclade K,” a new variant of influenza A H3N2.
This variant has multiple mutations in a protein on the surface of the virus called hemagglutinin, making