THE pre-monsoon mosquito survey of the Directorate General of Health Services that has found a high density of Aedes mosquito in Dhaka is worrying. This suggests the failure of mosquito control programmes. Dengue prevention efforts of the south city authorities, as the survey finds, are worse than efforts of the north city authorities. The directorate in April surveyed 99 city wards and found a high mosquito density in 47 wards in the south and 30 wards in the north. The average Breteau index used to weigh dengue risks was recorded at 18.89 in the south and at 16.39 in the north. The Breteau and Household indexes, however, show that areas under both the authorities are at high risks of dengue. While the authorities need to take dengue prevention seriously and step up their efforts, the response of the south city authorities to the findings is shocking. The officials implicitly denounce the findings, saying that there would be more dengue cases in areas under their jurisdiction if the Breteau index is above 20 in the 30 wards. What the city officials have missed is that the high-risk dengue situation is the result of their inaction as the dengue outbreak threat during the monsoon season is always there and does not come without warning.
The survey that has been conducted for the past several years has not been successful in making city authorities act on the findings and recommendations. In May 2023, a similar survey reported that mosquito density in Dhaka was at its highest in five years. That time, the director of the Communicable Disease Control Programme said that essentially everyone living in Dhaka was at risk of contracting dengue. The early warning was not taken seriously, which became evident as Bangladesh witnessed more than 3.21 lakh hospital admission and 1,705 death in 2023, the highest number of dengue death since the health services authorities began keeping track of the disease. What is disappointing is that the authorities concerned are routinely engaged in conducting surveys and issuing warnings of a probable outbreak, but the authorities fall short of taking effective preventive action. In January鈥揗ay, the health services directorate general already recorded 2,726 cases and 33 deaths across the country. The dengue situation is additionally concerning as the country has undergone several episodes of heat waves, which are considered unconducive for the breeding Aedes mosquito. The reported dengue cases indicate a possible genetic mutation, an under-researched reproductive behaviour of the vector that needs to be understood for an effective prevention strategy.
It is imperative for the government to make city corporations and other public agencies take urgent steps to control the breeding of Aedes and redouble their efforts in mosquito control, including action against non-compliant homeowners, a routine drive to clean canals and other water bodies and a routine and systematic use of insecticides to kill the larvae. The government must use the findings of the pre-monsoon mosquito survey to work out an effective dengue prevention and mosquito control strategy. The surveys are, otherwise, nothing but a futile exercise and a waste of public money.