H3N2 alert: Key warning signs you shouldn’t ignore

Written by: Sneha Jajoo Reviewed by: Dr. Swati Mishra 18 September 2025

[{"selector":"#anim-7b74e60b-0d07-4bc7-ae20-85feeb3dd317","keyframes":{"opacity":[0,1]},"delay":0,"duration":600,"easing":"cubic-bezier(0.2, 0.6, 0.0, 1)","fill":"both"}] [{"selector":"#anim-aa9ef986-f1d5-46c4-8d6c-2ef36fc2fbf9","keyframes":{"transform":["translate3d(0px, 173.22939%, 0)","translate3d(0px, 0px, 0)"]},"delay":0,"duration":600,"easing":"cubic-bezier(0.2, 0.6, 0.0, 1)","fill":"both"}] Flu-like illnesses are on the rise, especially in Delhi-NCR regions, and H3N2 is one of the key culprits. Knowing the signs early can help in timely care. Let's dive in. Photo Credit: Freepik

What Is H3N2 Infection?

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High Fever

[{"selector":"#anim-e333d0de-5057-424e-be8b-f91a94dd2150","keyframes":{"opacity":[0,1]},"delay":0,"duration":600,"easing":"cubic-bezier(0.2, 0.6, 0.0, 1)","fill":"both"}] [{"selector":"#anim-7a0da576-af40-4279-a844-0f49f327aea4","keyframes":{"transform":["translate3d(0px, 232.14937%, 0)","translate3d(0px, 0px, 0)"]},"delay":0,"duration":600,"easing":"cubic-bezier(0.2, 0.6, 0.0, 1)","fill":"both"}] [{"selector":"#anim-9cecf45b-f192-4ff7-af12-cbe585c36d6f","keyframes":{"opacity":[0,1]},"delay":0,"duration":600,"easing":"cubic-bezier(0.2, 0.6, 0.0, 1)","fill":"both"}] [{"selector":"#anim-843ee4d0-2e92-48ee-a3c0-bed6d410a807","keyframes":{"transform":["translate3d(0px, 886.72879%, 0)","translate3d(0px, 0px, 0)"]},"delay":0,"duration":600,"easing":"cubic-bezier(0.2, 0.6, 0.0, 1)","fill":"both"}] One of the earliest and most common symptoms is a sudden spike in body temperature. Photo Credit: Freepik

Sore Throat & Runny Nose

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Severe Fatigue

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Persistent Cough

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When to Seek Help

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