New Delhi: H1N1 influenza cases are rising across several Indian cities, with Delhi and Bengaluru emerging as key areas of concern. Delhi has recorded 1,777 H1N1 cases so far this year, including 114 new infections reported on August 20. The capital has recorded 2,602 influenza cases overall, comprising 2,392 Influenza A and 210 Influenza B infections.
Despite the sharp increase, health authorities have stressed that there is no evidence of a new or more dangerous H1N1 strain circulating in India. The Indian Council of Medical Research (ICMR) has said the predominant virus is the known A/Missouri/11/2025 (H1N1) pdm09 like strain, which has been circulating since 2025 and remains well matched with recommended influenza vaccines.
The rise is being linked largely to seasonal influenza activity during the monsoon, rather than a new pandemic threat. Former WHO chief scientist Dr Soumya Swaminathan has also described the increase as a seasonal uptick and said there is no reason for panic.
Bengaluru, meanwhile, is experiencing sustained influenza transmission. Karnataka recorded 4,212 laboratory confirmed influenza positive cases across 32 districts by August 22, compared with 4,583 cases during the whole of 2025 and 3,903 in 2024. Bengaluru alone had reported 2,070 laboratory confirmed influenza cases by August 22.
Doctors say H1N1 typically causes fever, dry cough, sore throat, body aches, fatigue and weakness, with some patients also experiencing nausea. Most people recover with appropriate care, but complications can include pneumonia, breathing difficulties, low oxygen levels and, in severe cases, acute respiratory distress syndrome (ARDS).
Children, older adults, pregnant women and people with underlying medical conditions or weakened immunity require particular caution. Doctors advise people with flu like symptoms to avoid close contact with others, maintain hand hygiene, improve ventilation and seek medical advice early when symptoms are severe or worsening.
The key message from health authorities is clear the numbers deserve attention, but they do not indicate a new H1N1 threat. Continued surveillance, early treatment and sensible precautions remain the best defence as India moves through the current flu season.
ALSO READ: Delhi-NCR H1N1 Cases On Rise, Doctors Warn Of Severe Respiratory Symptoms