Aedes mosquito higher at bus terminals, railway stations

Most of the aedes mosquito larvae are found in abandoned tyres generally in bus terminals, depots and railway stations, says a survey.

The survey was conducted by the Communicable Disease Control (CDC) unit of Directorate General of Health Services (DGHS).

The CDC with the help of four teams of entomologists carried out the study in 14 areas of the capital between 31 July and 4 August. The DGHS published a survey report on its latest findings on its website Sunday.

CDC programme manager (dengue) MM Akhtaruzzaman said to Prothom Alo, “The survey finds the aedes mosquito population is huge in 86 per cent areas of the capital (Dhaka). This situation is very helpful for dengue infection.”

The CDC conducts mosquito surveys three times a year. In March this year, the DGHS unit conducted a survey in 100 areas of two city corporations in Dhaka.

Publishing the report, the CDC warned of an outbreak of mosquito-borne diseases in the rainy season if no effective measures are taken.

However, the two city corporations -- Dhaka North (DNCC) and Dhaka South (DSCC) -- instead of taking any effective measures, went on spraying ineffective insecticides.

In the second survey, conducted in 100 areas of Dhaka between 17 and 27 July, the CDC found the mosquito population rose by 14 times than it was in March.

At the same time, mosquito-borne dengue spread across the country, including Dhaka.

The latest survey is an additional survey. It put emphasis on bus terminals, railway stations, slums, metrorail project areas, police lines and hospitals.

The mosquito survey index is known as ‘Breteau Index’. Out of 14 areas, the latest survey report finds the Breteau Index (BI) higher than 20 in 12 areas. This suggests mosquitos or larvae were found in 20 pots of every 100 in those areas. The BI was 40-60 in at least four areas.

The CDC team said generally the mosquitoes breed in the abandoned tyres of bus, truck, motorcycle or bicycles.

“Aedes mosquito prefers dark and cool place to live in. They get it in the tyres since there’s no flow of air there,” said Kabirul Bashar, professor of Zoology department at Jahangirnagar University.

“The water accumulated in the tyres is suitable for larvae,” he added.

On the other hand, the number of aedes mosquitos is more at bus terminals, bus depots and railway station.

Hundreds of thousands of people started leaving Dhaka city by buses and trains to celebrate Eid-ul-Azha with their near and dear ones just before two days of publishing the CDC survey report.

*The report, published in Prothom Alo, has been rewritten in English by Shameem Reza