What Is H3N2 Flu, Spreading Across Delhi-NCR? Symptoms, Diagnosis And Treatment Here

(MENAFN- Live Mint) Complains of fever, cough, itchy throat and flu-like symptoms have ignited discussions around H3N2 flu. According to a recent study conducted by LocalCircles, around 69% of households in Delhi, Gurugram, Noida, Faridabad and Ghaziabad reported at least one individual with symptoms such as high fever, cough, sore throat and fatigue, primarily attributed to H3N2. The survey, which covered around 11,000 respondents, compared the results of September 2025 to their last survey conducted in March 2025.

Let's find out what is it, how is spreads and what are its symptoms. Later we will shed light on its diagnosis and treatment.

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It is a respiratory viral infection which primarily affects people over 50 years and under the age of 15, according to Apollo Hospitals. A subtype of the Influenza A virus, H3N2 is characterised by surface proteins - hemagglutinin (H3) and neuraminidase (N2). These surface proteins mutate frequently which make immunity vulnerable by reducing effectiveness of vaccination.

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H3N2 flu is communicable and people in closed spaces living in close proximity with the infected person are more at risk of catching the infection. It spreads primarily through respiratory droplets that are released during coughing, sneezing or talking. One can also catch the infection by coming in contact with contaminated surfaces.

Those individuals who haven't been exposed to the virus before or whose immune systems are weak are more susceptible to catch the H3N2 flu, especially children, elderly, pregnant women and those individuals with chronic conditions such as diabetes, asthma, heart diseases or other chronic ailments.

Gangaram Hospital Dr Atul Kakar said, "This virus in not new, it's an old virus. A special strain of this virus is spreading nowadays. This strain spreads when there is change of weather. Normally symptoms are like ordinary cough, cold but some people have breathing difficulty, high fever. In some cases, patients are hospitalised but in majority of cases this virus in self-limiting. People generally recover in 3-5 days," PTI reported.

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Crowded living conditions in schools, nursing homes and prisons are the hot spots where this contagious infection can be transmitted easily.

Symptoms of H3N2 flu

H3N2 infection symptoms typically begin with sudden high fever, chills, sore throat, headaches, muscle, body aches, fatigue, abdominal pain and sometimes gastrointestinal symptoms like nausea and diarrhoea.

Diagnosis of H3N2 flu

Though most cases are diagnosed clinically, H2N3 virus can be detected through culture, throat swabs or rapid influenza diagnostic tests and antibody tests.

Treatment of H3N2 flu

Although high-risk groups may require hospitalisation, but majority can recover at home with supportive care including rest and hydration. Administration of antiviral drugs like oseltamivir in early stages may be necessary in some cases, only after recommendation of medical experts. Warm saline gargles and steam inhalation can provide relief in case of throat discomfort.

Gastroenterology Dr Aditya Gudheniya in a post on X stated,“Oseltamivir works against H3N2 by blocking virus release (neuraminidase inhibitor). If started within 48 hrs of symptoms onset , it cuts illness by 1–2 days & lowers risk of severe disease/complications (especially in high-risk groups like elderly, pregnant women, immunocompromised, or those with comorbidities).”

According to Indian Council of Medical Research (ICMR) recommendation, physicians must treat H3N2 influenza primarily with symptomatic treatment rather than antibiotics.

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