City dwellers continue to suffer as the mosquito menace appears to have made a comeback in many parts of the capital after the authorities concerned have failed to conduct cleanliness programs and destroy breeding grounds of mosquitoes.
Residents in various areas, including Uttara, Mirpur, Rampura, Old Town, Dhanmondi, Hatirpool, Azipur, Lalbagh and Mohakhali, said that the growing number of mosquitoes had turned into a menace and become intolerable.
Some said that authorities were not spraying insecticides while others said that mosquitoes were showing no sign of retreat even after using pesticides.
The menace has added to the woes of city residents amid the sufferings from intense traffic congestions and water crisis in many areas of the capital ahead of summer.
Mosquitoes spread some viruses and diseases, including Zika virus, West Nile virus, chikungunya, dengue and malaria, with dengue remaining a public health concern in Bangladesh as it has claimed many lives over the years.
The rise in the number of mosquitoes comes on the eve of summer when there would be rains, with dengue feared to be turning alarming.
In 2021, at least 28,429 dengue patients were hospitalized and at least 105 of them succumbed to the disease, the second highest yearly dengue hospitalization and the second highest yearly dengue deaths since 2000 when the menace appeared officially in Bangladesh.
Meanwhile, since January 1, 2022, some 160 dengue patients have been hospitalized, among whom 126 were hospitalized in January, 20 in February and 14 in March. But no dengue death was officially reported this year.
Ekushey Padak- and National Film Award-winning actress Dilara Zaman, a resident of Uttara Sector-12 said, ‘We can’t even open our doors and windows due to the excessive rise in the number of mosquitoes. If we open a door for someone to come in, mosquitoes take no time to enter the house.’
Though city corporation employees are spraying insecticides, it’s not working at all, she said.
‘It puzzles me when I think about the efficacy of the insecticide being used as it fails to curb mosquitoes,’ she added.
She further said that others in the unit she worked in also faced the same mosquito problem while shooting for a production.
‘We also fear a fresh outbreak of dengue and other mosquito-borne diseases,’ she added
Mohammad Rafiq, a caretaker at a house near Azipur Dayra Sharif, said that it became extremely difficult for people like them to perform their duties due to the abnormal rise in the number of mosquitoes for the past few weeks.
‘None has come from the city corporation to spray medicine to eradicate mosquitoes for a long time,’ he said, adding that bites of some mosquitoes are more painful than others.
Mohammad Ratul, a resident of Mirpur-2, also said that he had not seen anyone spraying insecticides for quite some time.
They are unable to sleep even inside mosquito nets or after using mosquito coils, he further said.
Experts blamed lack of cleaning canals, drains, ditches and other dirty places as a reason for the rise in mosquitoes in many areas.
They said that the authorities should examine the field-level efficacy of the adulticide and larvicide they use to destroy the breeding grounds of mosquitoes.
According to Jahangirnagar University zoology professor and vector management expert Kabirul Bashar, the number of culex mosquitoes usually increases in March but lack of adequate measures on the part of the authorities to control the mosquitoes puts city residents to sufferings.
He too raised the question as to why the number of mosquitoes was not coming down even after spraying insecticides.
‘After the city authorities sprayed larvicide after cleaning the canals, drains and ditches, the number of mosquitoes should have decreased vis-a-vis the current situation,’ he added.
He said, ‘The adulticide used showed some 90 per cent efficacy in laboratory test but the efficacy in the field was found to have about 20 per cent.’
Kabirul, however, advised that the city authorities should carry out round-the-year measures to prevent dengue as, he said, no months would be found without dengue cases.
‘We are now conducting a pre-monsoon survey. The authorities should remove the containers, pots, etc and destroy the breeding grounds before rains begin in order to check outbreaks,’ Kabirul added.
Nazmul Haq Saran, a resident of the Sheikh Saheb Bazar neighborhood in the Old Town, said, ‘The sufferings due to mosquitoes in our area have become intolerable. We have not seen city corporation people spray insecticides for about a month to control the mosquito menace.’
Mahadi Hasan, a resident of Mohakhali, who works at South Bangla Agriculture and Commerce Bank, said that the rising number of mosquitoes in their area might be for dumping garbage in empty spaces and plots.
According to epidemiologist Abu Muhammad Zakir Hussain, culex mosquitoes usually lay eggs in dirty water while Aedes mosquitoes in clean water.
‘Cleanliness is very important for combating culex mosquitoes,’ he added.
He noted that the efficacy of adulticide was lower in the field compared to laboratory tests across the globe as lab tests are held in an artificial environment.
The efficacy of adulticide, he hastened to add, also depends on the quality and the price, adding that low price adulticide does not work as much.
‘We should first clean dirty places like canals, drains and ditches and then use larvicide in these places to have a maximum effect,’ he advised.
Dhaka South City Corporation CEO Farid Ahmed said on Friday that it was impossible to destroy 100 percent of mosquitoes as many private organizations kept their places dirty.
‘Our employees for the job, 1,050, are spraying larvicide and adulticide twice a day. We are also announcing our spraying programs by microphones of different mosques. We did not hear any complaint about not spraying insecticides,’ he added.
He further said that they had started cleaning canals and drains in the beginning of the year and the work would be continued throughout the year.
Asked about the field-level efficacy of the adulticide they use, he said that they had stocked adulticide after conducting both field and lab tests and found 90 per cent efficacy in both tests.
He said that their entomologists, by testing samples, had found larvae in stagnant dirty water but not in clean water flows.
DNCC CEO Selim Reza said that they had taken crash programs to contain the mosquito menace but they could not destroy breeding grounds of mosquitoes in all private properties.
‘We held a meeting two days ago. We are trying to control mosquitoes everywhere. We have instructed our officials concerned to take legal action if any private property owners keep mosquito breeding grounds from destruction in their property,’ he added.
He said that they were working to contain both Aedes and culex mosquitoes at the same time.
Asked about the state of cleanliness, he said, ‘Our waste management teams are working tirelessly to keep the canals and drains clean. We hope that the situation will return to normal soon.’