New Delhi, India – The Indian Council of Medical Research (ICMR) on Sunday clarified that no new strain of H1N1 has been identified in India, stating that the currently circulating Influenza A (H1N1) viruses belong to the A/Missouri/11/2025 (H1N1) pdm09-like virus strain. “These viruses belong to clade 6B.1A.5a2a, subclade D.3.1.1, and have been in circulation since 2025,” ICMR said. It added that the influenza strains are well matched with the vaccine strains recommended for the Northern Hemisphere, and that seasonal influenza, including H1N1, is mostly self-limiting.
The clarification comes amid a rise in seasonal Influenza A(H1N1) cases, commonly called swine flu, during this monsoon season, especially in major cities. Delhi has reported 1,777 confirmed H1N1 cases so far this year, including 114 new cases on August 20. Karnataka has registered over 4,000 cases, with more than half reported from Bengaluru. Rising influenza activity has also been reported in Mumbai, Chennai, and parts of Kerala. Common symptoms include fever, cough, headache, and body ache, with most people recovering with appropriate care and rest.
ICMR emphasized that young children, elderly persons, and individuals with underlying medical conditions may be at a greater risk of complications and should consult a doctor if symptoms persist or worsen. The Union Health Ministry is closely monitoring the situation through regular surveillance and undertaking necessary public health measures. The National Centre for Disease Control (NCDC) maintains a nationwide influenza surveillance network and recommends seasonal influenza vaccination based on WHO strain recommendations. For the 2025–26 season, India’s recommended trivalent vaccine included H1N1, H3N2, and B/Victoria components, with circulating Indian H1N1 strains aligning with vaccine strains. “People at higher risk should consider annual vaccination and seek medical advice promptly if flu symptoms become severe,” said Anil Bansal of the Delhi Medical Association.
