Briefing note – Influenza A(H3N2) subclade K (J.2.4.1), considerations for the Americas Region – 11 December 2025 – PAHO/WHO

The Pan American Health Organization / World Health Organization (PAHO/WHO) is issuing this Briefing Note to inform Member States about the influenza A(H3N2) situation related to subclade K in various regions of the world and to reiterate the…