Ctg City Corporation’s mosquito eradication drive yields little result

Chattogram City Corporation has not been able to implement the recommendation of using effective insecticides for mosquito control even in a year, with an audit by experts finding that the corporation has spent crores on ineffective mosquitocides.

Even the regular use of fogger machines and spraying insecticides failed to yield the expected results. As a result, the number of patients affected by dengue has crossed the thousand mark within the first 10 months of the year.

The city corporation says that the medicine recommended by the expert team does not have the approval of any organisation. 

However, a letter has been sent to the Pathology Department of the Department of Agriculture Extension recommending experiments on a drug. If approved, the herbal insecticide 'Moskuban' will be used experimentally in the hotspots of mosquito breeding.

According to the District Civil Surgeon's office, a total of 36 patients were infected with dengue, a mosquito-borne disease, in Chattogram district in the first six months of this year. Then 64 were infected in July, 114 in August and finally 601 dengue patients were detected in September. Another 343 people were identified in the first ten days of October, according to the outbreak report.

Since January this year, 1154 people have been infected and 11 people have died, whereas in 2020 there were 17 cases and 1 death and in 2021 a total of 271 cases and 5 deaths were reported due to dengue.

Chattogram District Civil Surgeon Dr Mohammad Ilias Chowdhury said, "Due to the rains in May, the Aedes mosquito continues to breed, so the rate of infection is increasing."

He also said, "Dengue outbreaks usually occur from June to September. It starts decreasing from the first week of October. But this time it is increasing instead. For the past few days, more than 50 dengue patients have been detected daily. This is alarming. We have asked the city corporation to take various measures to kill mosquitoes."

According to information from the city corporation, it spends more than a crore taka annually on purchases of machines and spraying medicines.

The city corporation sprays larvicides with a spray machine to kill mosquito larvae and adulticide with a fogger machine to kill adult or flying mosquitoes. The city corporation spent Tk1.05 crore to buy mosquitocides in the 2021-22 fiscal year. In the current fiscal year Tk6 crores have been allocated. Recently, the city corporation also completed the process of purchasing 10,000 litres of adulticide and 2,000 litres of larvicide.

In 2021 M Rezaul Karim Chowdhury took the initiative to test the effectiveness of mosquitocides immediately after taking office as the city mayor. A research study by expert teachers of Chattogram University showed that only 14% mosquitoes were killed when a maximum dose of 16.9 millilitres of adulticide was sprayed in one litre of kerosene with a fogger machine. However, if the same amount of insecticide is sprayed by a spray machine, 100% of mosquitoes are killed. However, this level of medicine is harmful to the environment, so the city corporation does not use it. Besides, mixing 16.9ml larvicide in 1 litre kerosene yielded 100% results.

As uncontrolled use of chemical pesticides is harmful to humans, animals and the environment, the expert team recommended the introduction of biological control methods as an alternative to mosquito control. These include - control of larvae through fish farming, destruction of larvae using microorganisms, destruction of larvae using plant extracts, etc. But the city corporation did not implement these recommendations of the research team even in one year. However, the mosquito eradication program is still going on with insecticides that are less than 20% effective, according to the experts' audit.

Mohammad Omar Farooq, member secretary of the expert team and associate professor of botany department of Chattogram University told The Business Standard, "If you want a permanent solution, you have to go back to using biological methods. There is no alternative. Besides, mosquito breeding can be easily controlled by importing Bti technology, which is used as a larvicide to kill larvae before they can grow into adults that can bite people."

He also said, "If neem, mint and tulsi trees are planted on the roadsides, the mosquito menace will be reduced a lot. The city corporation and the Chattogram Development Authority are also planting trees along the roads for beautification. They can plant the recommended trees."

The Chattogram City Corporation on 9 September wrote to the Director General of the Department of Agricultural Extension MdBenjirAlam requesting a report on the herbal mosquitocideMoskuban.

The city corporation expects the report by next week.

The corporation's Acting Chief Conservancy Officer AbulHashem told The Business Standard, "We have written to the Department of Agriculture Extension for approval of a drug as per recommendations by experts. They are experimenting on it. Initial use will begin in 'mosquito hotspots' if it performs well."

He also said, "We have identified the city's Pahartali, Doublemuring, Agrabad, Halishahar and Bahaddarhat areas as hotspots. Research by the Institute of Epidemiology, Disease Control and Research has revealed that mosquito breeding also takes place in abandoned tires and roof corners. We are conducting daily operations. Those who do not clean their roof gardens are being fined."

Earlier the mosquitocides cost Tk500-600 per litre. The cost of new medicines will be Tk1200 per litre, added AbulHashem.