Chennai, July 21 (IANS) As Chennai braces for the peak dengue season, the Greater Chennai Corporation (GCC) has intensified vector control and source reduction measures across the city following a sharp rise in dengue cases this year.

From January to July 8, 2025, the city recorded 522 cases — up from 381 during the same period in 2024.

The civic body’s vector control department has ramped up efforts, especially in high-incidence zones.

Adyar emerged as the worst-affected area this year, reporting 111 cases, followed by Shollinganallur with 63.

In June alone, over 23 tonnes of waste, including 2,690 kg of used tyres and 20,455 kg of water-holding containers like broken pots and drums, were cleared citywide to eliminate mosquito breeding grounds.

Notably, Adyar accounted for the highest waste removal at 3,596 kg. Officials noted that Aedes mosquitoes, which transmit dengue, breed in clean stagnant water often found inside homes.

“Water collected inside unused tyres, broken containers, sunshades, and even refrigerator trays can serve as breeding spots,” a vector control officer with the GCC said.

Historically, Adyar has consistently reported the highest dengue cases in the city, with over 250 cases in both 2023 and 2024. In contrast, zones like Royapuram and Tondiarpet generally report fewer cases, averaging around 57 and 63 annually.

However, public health experts caution that these numbers may reflect better disease reporting in some areas rather than actual incidence. Residents in low-reporting zones, such as Old Washermanpet, claim many cases go unnoticed.

Dengue cases in Chennai typically surge between August and October, with the peak in September and October. This trend aligns with data from the World Health Organisation’s 2020 Dengue Bulletin and studies by Tamil Nadu’s Directorate of Public Health.

Intermittent rains during the southwest monsoon are particularly conducive to breeding, while heavier northeast monsoon rains tend to wash away larvae. Dr T.S. Selvavinayagam, Director of Public Health, highlighted two major dengue outbreaks in Tamil Nadu — in 2012 (13,204 cases) and in 2017 (23,294 cases).

“We have around 10 days to act before the next breeding cycle begins,” he warned, urging proactive vector control.

While some residents blame ongoing infrastructure projects like the Metro Rail and stormwater drains for impeding vector control, officials maintain that efforts are ongoing.

“We have 2,400 domestic breeding checkers inspecting over 500 homes each week year-round,” a senior official said.

“Fogging operations and penalties are enforced wherever dengue is reported. But public participation is crucial — keeping one’s surroundings clean is the most effective preventive measure.”

–IANS

aal/dpb