Swine flu outbreak in Delhi swamps clinics and hospitals

India is battling a surge in H1N1 flu infections, prompting the federal health ministry to step up surveillance and hospital preparedness.

The national capital New Delhi has recorded 1,777 cases this year, almost eight times the number (229) reported during the same period in 2025.

Dr Randeep Guleria, a senior pulmonologist and director of Medanta Medical School, Gurugram, says the H1N1 cases are much higher than reported. 

“It’s quite likely that the reported numbers are an underestimate because they depend on how many people are tested,” Guleria said. “If you speak to patients admitted to hospital who test positive for H1N1, you often find that other members of their family have similar symptoms, although they have not been tested.”

“There is a surge and we are seeing a lot of patients. We are testing only those who come to hospital and are more seriously ill,” Guleria said.

H1N1, commonly known as swine flu, is a subtype of influenza A. It is a contagious respiratory infection that can cause fever and cough and in severe cases it can lead to pneumonia and respiratory failure. 

Officials at the Indian Council of Medical Research said the rise did not mean the emergence of a new strain of the virus.

The surge comes during India’s rainy season, when seasonal influenza and other respiratory infections typically increase.

Doctors in Delhi say they are seeing more patients with high fevers, persistent coughs and flu-like symptoms, although most cases remain mild.

The H1N1 cases have been reported beyond New Delhi. The metro cities like Mumbai, Chennai and Bangaluru have reported a high number of cases, although the pattern is not uniform across the country. 

Doctors in Bangaluru have reported more influenza A infections among children, with some developing pneumonia and respiratory distress.

India’s health minister JP Nadda said there was a need for continued vigilance and robust surveillance. He has asked officials to monitor unusual increases and clusters of cases and ensure hospitals could respond quickly.

“Swine flu (H1N1) can show up through symptoms such as fever, cough, sore throat, headache, runny nose, body aches and fatigue… If you experience these symptoms, seek medical advice at your nearest healthcare centre,” the health ministry said on X.

Delhi’s health minister, Pankaj Kumar Singh, said the capital had enough beds, doctors, medicines and medical equipment to manage the increase. “Delhi is fully prepared to deal with the present health situation,” Singh said.

India has had several waves of H1N1 since the virus emerged globally in 2009.

The infection, commonly called swine flu, became a recurring seasonal respiratory illness after the 2009 pandemic rather than disappearing from circulation.

India recorded 3,320 H1N1 cases and 14 deaths in 2025, according to Ministry of Health data.

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