Rise of the dreaded dengue in Chennai

CHENNAI: It’s raining mosquitos, and predictably, their sting leads to infections and illnesses that are, more often than not, fatal. After neighbouring states of Tamil Nadu recorded an alarming surge in dengue cases and related fatalities, the State Health Department has intensified the surveillance of fever cases.

In TN, the spread of dengue infection is under control with 5,554 cases and one death this year until July 1.

However, the rains can lead to an outbreak, warn experts. Therefore, there is an urgent need to strengthen domestic-breeding checks, especially among construction sites, as these remain one of the most common breeding sites for mosquitoes.

Breeding places

Residents lament over the debris and garbage that are dumped in empty plots and construction sites. They also accuse the Greater Chennai Corporation (GCC) for its lackadaisical approach in addressing this.

“Abandoned vacant plots on Thatchi Arunachalam Street in Mylapore, and the construction site in and around Mylapore, have become dumping grounds for residents and small eateries. With the northeast monsoon just two months away, till now, the GCC has not undertaken any kind of preparation. In 2023, during the northeast monsoon, rain water from the Chittrakulam Tank overflowed into the streets, flooded the area, and even entered low-level houses. It took days for the stagnated water to dry up,” recalled Ramesh Ramadoss, a civic activist in north Chennai. “Abandoned vehicles on the roads and lanes are also a safe haven for rats, mosquitoes, and other vector-borne illnesses.”

Along the railway tracks on the north side of Perambur High Road, there was a natural waterway. Now, with people choosing to dump garbage and debris, it looks like an ever-present stagnant water.

“While constructing the compound wall, we asked the railway authorities to clean the waterway but till date, nothing has been done. The damaged portions of the storm water canal in the north side of the Perambur High Road is filled with sewage,” fumed C Raghukumar, a resident of Perambur.

Additionally, intermittent spells in the city have led to sewage overflow on the streets. Residents pointed out that there were no regular inspections during or before the monsoon.

“Bleaching powder is not sprayed to prevent mosquito breeding. Only after dengue cases or deaths are reported in the locality, authorities take steps to eradicate mosquitoes and clear stagnated sewage,” rued R Marakadham, a resident of Maduravoyal.

Urbanisation at fault

Though dengue cases were earlier confined to urban areas only, it has now spread to rural areas due to rapid urbanisation, and the implementation of several development schemes.

“The infrastructure developmental projects in various places have become a breeding site for the Aedes large, and especially with intermittent rainfall, the risk increases,” stated Jayavel, a domestic breeding checker. “Due to lack of awareness, people, especially in the rural areas, get offended when we conduct inspections. So we show them samples of larvae in their surroundings.”

Though there were around 4,000 dengue cases until May in TN, officials from the State Health Department claimed that there were no outbreaks pointing to only 1,500 cases in June and July. Also, there have been no fatalities due to the infection. However, they stress on precautionary measures and timely hospitalisation to reduce mortality due.

Prevention

Dr Sujatha KC, general physician, opined that risk of dengue fever surges due to ideal conditions for mosquito breeding, which has been widely reported in Bengaluru with over 7,000 cases this year.

Bengaluru has seen a 215% rise from the end of May to the end of June – 83% increase in the last month, as per the recent insights by Practo.

“Community-wide efforts to mitigate transmission are crucial. To prevent mosquito breeding, you must clear stagnant water in large containers, trim the lawns and gardens, and use mosquito dunks or lids for storing water where drainage isn’t possible,” she explained. “Additionally, boost your immunity with a diet rich in fruits like papaya, kiwi, and citrus, as well as incorporating garlic, ginger, and turmeric while cooking. Staying hydrated can offer some protection against the disease.”

In a recent advisory, Dr T S Selvavinayagam, Directorate of Public Health and Preventive Medicine, instructed officials to ensure that all government hospitals (GH) and other healthcare establishments are free of mosquito breeding. Officials were told to monitor entomological indices and vector-control activities in areas with high vector density and ensure chlorination to prevent contamination of water sources.

GHs and offices have been instructed to be made Aedes free. Hospitals must have additional bed strength in the existing fever wards in the probability of an outbreak.

Officials must also educate the community, schools students and residential welfare associations to keep their houses and premises free of mosquito breeding. With dengue cases rising in Karnataka and Kerala, District Health Officers have been asked to initiate timely preventive and control measures and keep vigil in the bordering areas.

As many as 38,000 domestic breeding checkers are deployed across the State to ensure dengue-control measures are in place. City health officer Dr M Jagadeesan said that breeding checkers have carried out field inspections regularly, and also created awareness among the residents on vector-borne diseases.

“Wherever there is garbage or debris on the roads including vacant plots, it has been cleared immediately. Zonal level authorities inspect construction sites and impose penalties on those who have violated vector-control protocols,” he added.