CHENNAI: In the first 18 days of September, Chennai recorded a total of 614 dengue cases, which is already 18% higher than the number of cases recorded in the entire month of September last year. Similarly, August registered an alarming 66% rise — 605 cases in total – compared with the 364 cases registered in August 2025. The steep rise in dengue cases over the last two months has pushed the total to 2,600 so far this year, which is relatively lower compared with the number of cases until September in 2025 (2,795) and 2024 (3,594).
Greater Chennai Corporation Commissioner G S Sameeran, referring to the civic body’s data, said that dengue cases, over the past decade, have followed an upward trend during the pre-monsoon period in August and remained in peak until at least November or December. “Though there is a surge, 95% of the cases are self-limiting, with only 5% requiring hospitalisation,” he said.
To intensify dengue prevention measures, the civic body has deployed 3,690 domestic breeding checkers (DBCs) in 15 zones, he said. The workers would cover 80 to 100 houses a day and carry out preventive measures, he said, noting that the intermittent rains over the past few days might have created breeding grounds for Aedes mosquito larvae, which cause dengue.
Over the last 20 days, the civic body has levied a total penalty of Rs 5.56 lakh on commercial institutions for not following to dengue prevention measures. On Sunday, the GCC chief inspected the hostel in Chepauk, which houses nearly 750 students; several of them volunteered for the mosquito-control activities.
As the students raised complaints regarding hygiene and infrastructure, Sameeran said hygiene-related issues would be addressed immediately, while assuring them that the civic body would work with the respective institutions to address infrastructure issues gradually.
Meanwhile, several residents questioned the civic body over the non-deployment of drones to spray larvicide along waterbodies over the past year. A senior official told TNIE that the corporation has increased manual spraying and that drone spraying is carried out only to control Culex mosquitoes that do not cause dengue.
YOY decrease in cases
According to data from the Directorate of Public Health and Preventive Medicine (DPH), dengue cases statewide have been on the decline for three consecutive years since 2023. The state recorded 56,863 cases in 2023, 46,971 in 2024, and 25,585 in 2025, while 17,049 cases have been reported so far in 2026. Meanwhile, dengue deaths statewide stood at 12 in 2023, 13 in 2024, 12 in 2025, and nine so far this year.
Scrub Typhus
Director of Public Health and Preventive Medicine Dr A Somasundharam, in a video released by the department, said that other diseases such as scrub typhus are also being reported during the monsoon season. Scrub typhus is caused by the bacterium Orientia tsutsugamushi, which gets transmitted through chigger mites found in scrub and bushes. It usually begins with fever, along with symptoms such as tiredness, headache, body pain, and loss of appetite. If not treated early, the disease can lead to complications such as acute respiratory distress syndrome (ARDS) and myocarditis, said Dr PV Balamurugan of Madurai Medical College
(With inputs from Sinduja Jane)