New Delhi: Delhi has reported 1,777 cases of H1N1 influenza so far this year, with 114 new cases recorded on August 20, according to the latest data from the Delhi government.
A total of 2,602 cases of seasonal influenza, including Influenza A and Influenza B, have been reported cumulatively in Delhi in 2026. H1N1 accounts for the largest share of these infections, making it the predominant influenza subtype reported in the national capital this year.
Amid concerns over the rising number of cases, senior scientists at the Indian Council of Medical Research (ICMR) have clarified that no new H1N1 strain has been detected in the country and said there is no cause for panic.
ICMR says no new H1N1 strain is circulating
ICMR scientists said the Influenza A (H1N1) pdm09 viruses currently circulating in India belong to the A/Missouri/11/2025 (H1N1) pdm09-like virus strain.
According to the scientists, the viruses belong to clade 6B.1A.5a2a and subclade D.3.1.1 and have been in circulation since 2025.
They stressed that this does not indicate the emergence of a new H1N1 strain.
The clarification comes amid growing concerns about whether a new or more dangerous variant could be responsible for the increase in cases.
ICMR scientists also said the influenza viruses currently circulating are well matched with the vaccine strains recommended for the Northern Hemisphere.
H1N1 emerges as predominant subtype in Delhi
Delhi government data shows that Influenza A has accounted for the majority of seasonal influenza infections reported this year.
Of the 2,392 Influenza A cases recorded cumulatively until August 20, H1N1 accounted for 1,777 cases.
The H1 subtype accounted for 37 cases, while 138 cases were attributed to H3. Another 440 cases were classified under other Influenza A types.
In addition, Delhi reported 210 cases of Influenza B, taking the cumulative total of Influenza A and B infections to 2,602.
The trend is different from the previous year, when H3N2 was the predominant influenza subtype in Delhi. In 2026, H1N1 has emerged as the leading subtype.
Most infections are self-limiting
Seasonal influenza, including H1N1, is generally self-limiting, with many people recovering with rest and appropriate care.
Common symptoms include fever, cough, headache and body ache.
However, young children, elderly people and those with underlying medical conditions may face a higher risk of complications.
People whose symptoms persist, worsen or become severe have been advised to seek medical attention without delay.
Health authorities have also cautioned against self-medication and advised people to consult a doctor before taking medicines for influenza-like symptoms.
Delhi steps up influenza surveillance
The Delhi government said it is closely monitoring the seasonal influenza situation through the Integrated Disease Surveillance Programme (IDSP).
Morbidity and mortality associated with influenza are being tracked, while daily information on influenza-like illness and severe acute respiratory infections is being monitored through the IDSP-IHIP portal.
Regular updates are also being shared with senior authorities.
An inter-sectoral meeting was held on August 20 under the chairpersonship of the Secretary, Health and Family Welfare.
Representatives from the Municipal Corporation of Delhi, New Delhi Municipal Council, Cantonment Board, Education Department and Delhi Development Authority participated in the meeting.
The departments were directed to strengthen public awareness and information campaigns on the prevention and control of seasonal influenza.
Hospitals and districts asked to remain alert
The Delhi State Health Mission is holding daily review meetings with Chief District Medical Officers to monitor the situation.
Advisories have also been issued to hospitals and district health officials regarding the screening, reporting and monitoring of influenza cases.
The government has said technical guidelines on patient categorisation, treatment protocols, ventilatory management, mask use and home care are already in place.
Healthcare workers are also being trained and sensitised to ensure timely identification and management of influenza cases.
India generally sees two influenza peaks
Health authorities noted that seasonal influenza in India generally records two periods of increased activity during the year.
One peak typically occurs between January and March, while another is often seen during the post-monsoon period.
With the rise in cases, the public has been advised to follow basic preventive measures, including maintaining respiratory hygiene and washing hands regularly.
People may consider using masks in crowded places and avoiding unnecessary exposure to crowded areas, particularly when respiratory infections are circulating.
Limiting close contact with people suffering from respiratory illnesses can also help reduce the risk of transmission.
The increase in H1N1 cases has prompted Delhi authorities to intensify surveillance and public awareness efforts. However, ICMR’s clarification that no new strain has been detected offers reassurance that the rise is linked to a strain already in circulation.
Health authorities have urged the public to remain cautious and follow preventive measures while avoiding panic and misinformation.
