Mosquito density has doubled in the last two months in the capital, and if proper steps are not taken immediately, the menace will increase manifold by next March, warns a study.
"The density of mosquitoes is increasing rapidly in Dhaka and its environs. At present, the density is almost double that in December and January. Our study shows that mosquito density will quadruple in March unless urgent action is taken," Professor Kabirul Bashar of Jahangirnagar University zoology department, who led the study, told The Business Standard.
The study forecasted the huge infestation of mosquitoes based on the review of the mosquito density levels, temperature, humidity, rainfall, etc of Dhaka and its environs in the last six months, he added.
To find out how the mosquito density is increasing, samples were studied in six areas of Dhaka including Uttara, Gulshan, Mohammadpur, Khilgaon, Kathalbagan and Sadarghat of Old Dhaka. Research has shown that mosquito density is highest in low lying areas around Dhaka, he said further.
Why this rise in menace
Professor Kabirul Bashar said their research has shown that 98% of the mosquitoes at present are Culex that can cause filariasis. The presence of Aedes mosquitoes is about 1%. Mosquito density is increasing at present due to high temperature and humidity as well as the high amount of organic matter in the water.
Mosquitoes are now on the rise due to the favourable breeding environment. For example, Culex mosquitoes usually breed in stagnant water. Due to the lack of rain for a long time, the water in drains, ditches, ponds and lakes has now rotted.
What needs to be done
Entomologist Kabirul Bashar said crash programmes are required on an emergency basis to destroy adult mosquitoes and larvae. Wherever there is stagnant water, larvae killing drugs should be sprayed. And to control adult mosquitoes, larvicide should be applied regularly. At the same time, ditches, lakes, ponds and sewers have to be cleaned on a regular basis.
What the authorities say
Dhaka South Chief Health Officer Fazle Shamsul Kabir told The Business Standard that they have a year-long plan to eradicate mosquitoes.
"Steps are taken every month. That is why the situation was under control during the Culex mosquito season. We assure the people that mosquitoes will not increase next month," he said.