Dengue cases are climbing across India as the monsoon creates more breeding sites for mosquitoes. Tamil Nadu has recorded 16,334 cases and nine deaths between January 1 and September 16, 2026, according to state officials.

Delhi has reported 432 dengue cases this year, with 121 in September — the highest monthly count so far — according to the Municipal Corporation of Delhi. Ahmedabad logged 496 cases in the first 20 days of September, about 46 per cent of its total 1,084 cases this year.

Dengue spreads through the bite of infected Aedes mosquitoes, which breed in stagnant water. Tamil Nadu officials called the spread seasonal and not alarming, noting that 2024 saw 34,339 cases in the same period.

AIADMK leader Edappadi K. Palaniswami disagrees. He accused the state government of slow action, citing 17,348 cases as of September 21, and demanded medical camps and door-to-door checks. Health teams have stepped up house-to-house surveillance and cleared breeding sites.

Officials warn that October to December can bring more mosquito breeding, making continued prevention important.