The short spells of rain might bring cheer to rain-starved residents but they have also led to an increase in mosquito breeding across the city.
In the last few weeks, residents of various areas have been complaining of mosquito bites through the day and night. Health officials admit there are mosquitoes, but insist their density was not high. Vector-control measures were being taken up, they assured.
A resident of Nammalwarpet said mosquitoes were found in abundance in the area, and her neighbours were also complaining of the menace. “We close all the windows and doors at 5 p.m. to prevent mosquitoes from entering our home,” she said. There was a definite spike in the mosquito density after the rains, added Sheelu, a resident of M.K.B. Nagar.
P. Kuganantham, former city health officer, said it was natural for the mosquito density to go up after short spells of rain. “Breeding occurs in water collected after short spells of rain. It is important for the Chennai Corporation to identity hotspots of mosquito breeding in the city. For instance, the mosquito density has gone up in areas such as Ashok Nagar and T. Nagar,” he said. He recalled how the Corporation, in 2012, had taken up sector surveillance in which workers visited houses to check for breeding sources.
“We then identified hotspots in the city based on larval density, adult mosquito density, complaints from public and dengue cases. We marked these hotspots and took up breeding control measures. Fogging should be taken up in densely populated areas at dawn and dusk,” he explained. Health officials of the Chennai Corporation said they were targeting menace-causing vectors such as armigeres and disease-causing vectors such as Aedes aegypti separetely. The number of complaints on mosquito menace received from the public is comparatively low, an official said, pointing out that there were nearly 9,000 complaints during January to December 2018 as against 2,600 complaints so far this year.
“Vector control monitoring system is being carried out in waterways such as Adyar and Cooum. Works to clear water hyacinth are progressing. We are giving priority to areas where the density is high,” he said. Armigeres mosquitoes are a challenge, the official said. “These mosquitoes breed in septic tanks. Their bites are painful and cause rashes.”