Dengue Season: Delhi Cases Rise in September as West Bengal Declares October–November High-Risk
October 3, 2026: Health authorities in several states are stepping up mosquito-control measures as India enters the post-monsoon dengue peak season of October and November.
Delhi: September Brings the Sharpest Rise
According to Municipal Corporation of Delhi (MCD) figures reported in mid-September:
- Delhi recorded 432 dengue cases in 2026 up to September 12.
- 121 of those cases were in September alone, the highest monthly count of the year at that point, with 71 in the preceding week.
- West Delhi (57), Central Delhi (54) and Shahdara North (50) reported the most cases.
The total is lower than the same period in previous years: 619 in 2025, 709 in 2024 and 2,097 in 2023. Health experts caution that dengue numbers can climb quickly in October, and year-to-year comparisons can shift as the season progresses.
West Bengal: High-Risk Period Declared
IANS reported on September 28 that West Bengal recorded 10 dengue-related deaths through August 2026, lower than in 2025 and 2024. A death review committee found dengue was the cause in seven of those cases. The state administration has declared October and November a "high-risk period", and the Chief Secretary held a meeting with all district magistrates to review preparedness.
Why Cases Peak Now
Aedes mosquitoes breed in clean stagnant water left behind after monsoon rains, in coolers, flower-pot trays, tyres and construction sites. Warm temperatures in October speed up the mosquito life cycle. Doctors have also reported more cases outside the traditional season in recent years.
How to Protect Yourself
- Empty and scrub water containers weekly.
- Cover water tanks and dispose of containers that collect rainwater.
- Wear full-sleeved clothing and use repellents, especially in the daytime.
- Use nets or screens for infants, the elderly and anyone resting during the day.
When to Seek Medical Care
See a doctor for high fever during the season. Go to hospital urgently for severe abdominal pain, persistent vomiting, bleeding, drowsiness or restlessness, especially as the fever falls. Use paracetamol for fever as advised by a doctor and avoid ibuprofen and aspirin.
FAQ
Are dengue cases higher in 2026 than last year in Delhi?
Up to mid-September, Delhi's cases were lower than in the same period of 2025, 2024 and 2023.
When does dengue season end?
Cases usually decline as temperatures drop in late November and December.