H1N1 cases touch 1,700 in Delhi, Nadda reviews surveillance

JP Nadda stressed the need for continued vigilance, stronger surveillance and early clinical management to prevent further spread.

With H1N1 infections rising in the national capital, Union health minister JP Nadda on Friday reviewed surveillance and preparedness measures, with a particular focus on Delhi, which has recorded over 1,700 cases so far this year.

Union Health Minister JP Nadda reviews H1N1 influenza preparedness during a meeting, in New Delhi. (@MoHFW_INDIA/X)

The meeting, attended by Delhi health minister Pankaj Kumar Singh, assessed trends in influenza-like illness (ILI), severe acute respiratory infections (SARI), laboratory testing, and the readiness of hospitals to manage seasonal influenza cases, according to the Union health ministry.

Nadda stressed the need for continued vigilance, stronger surveillance and early clinical management to prevent further spread. He also directed officials to strengthen public awareness on respiratory and hand hygiene and urged people with persistent or severe symptoms to seek medical attention promptly.

Historical records suggest drop in cases

According to National Centre for Disease Control (NCDC) data, Delhi has recorded more than 3,000 H1N1 cases in three recent outbreak years – 4,307 cases in 2015, 3,627 in 2019 and 3,151 in 2024. This year’s tally of nearly 1,777 cases remains well below those peaks.

The data also shows that larger outbreaks do not necessarily translate into higher mortality. Delhi has not recorded any H1N1 deaths since 2019, when 31 people died as caseload touched 3,627.

In contrast, the city witnessed another major outbreak in 2024 without recording any deaths.

A similar pattern is visible nationally. India has experienced major H1N1 spikes in 2010, 2015, 2017, 2019, 2022 and 2024, although the outbreaks have not followed a fixed periodic cycle. In 2010, 20,604 cases resulted in 1,763 deaths, whereas a comparable caseload in 2024 (20,414 infections) led to 347 deaths.

Experts, however, caution that reported cases and deaths are influenced by testing intensity and healthcare access. States with weaker surveillance systems often report very few infections despite having much larger populations.

Delhi doctors ramp up preparedness

Doctors in Delhi said infections have increased sharply over the past fortnight. “If we test a symptomatic patient now, we are finding H1N1. It is spreading fast, but in healthy individuals, symptoms remain mild -- sore throat, chest pain, runny nose. However, we have also seen patients requiring hospitalisation, some even on ventilators. Those with severe symptoms are usually elderly or have underlying conditions,” said Dr GC Khilnani, chairperson of PSRI Institute of Pulmonary, Critical Care, and Sleep Medicine.

The health ministry said Friday’s review also examined hospital preparedness, including bed availability, critical care infrastructure and essential medical supplies.

“The health minister stressed close monitoring of influenza trends and proactive preparedness for early detection and timely clinical management,” the ministry said in a statement.

H1N1 is a subtype of the influenza A virus that emerged during the 2009 swine flu pandemic. Although the World Health Organization (WHO) declared the pandemic over in 2010, the virus continues to circulate as a seasonal influenza strain.

Common symptoms include fever, chills, persistent cough, sore throat, body ache, headache and runny nose. Some patients may also experience nausea, vomiting or diarrhoea. Doctors advise immediate medical consultation if symptoms progress to breathing difficulty, chest pain or bluish lips, particularly among elderly people and those with underlying illnesses.