The dengue outbreak in Bangladesh continues despite the end of the monsoon, with infections and deaths persisting towards the end of the year.
Intermittent rainfall in the second week of November has further raised concerns that the dengue season may last longer than usual.
Public health experts say higher temperatures and unexpected rainfall are creating favourable conditions for Aedes mosquito breeding, potentially sustaining the outbreak through November and even December.
According to the Directorate General of Health Services (DGHS), 155,668 people contracted dengue between January 1 and November 11 this year, nearly double the 80,634 cases recorded during the same period last year.
Dengue deaths also increased, from 318 during the corresponding period last year to 478 this year.
Hospitals under pressure
Despite the usual decline in dengue infections towards the end of the season, hospitals are continuing to face growing patient pressure, with shortages of beds in some facilities.
Afroza Akter Helen, a resident of Kathalbagan in Dhanmondi, described her difficulties finding a hospital bed for her one-year-old daughter after she tested positive for dengue.
She said she initially struggled to secure admission at Shishu hospital in Shyamoli and had to return home before eventually getting a bed the following day.
Meanwhile, the government has maintained that its early planning and coordinated measures have helped reduce dengue deaths.
On October 13, State Minister for Health Dr MA Muhit said the death rate had fallen by around 40% compared with previous years, attributing the improvement to specialised training for doctors and evidence-based treatment.
He said the government was not taking the situation lightly and was working to bring infections down to zero.
Why the season may last longer
Dr Mushtaq Hossain, former principal scientific officer of the Institute of Epidemiology, Disease Control and Research (IEDCR), said inadequate scientific efforts to destroy mosquito breeding grounds were undermining dengue control.
He explained that falling temperatures would gradually reduce mosquito breeding, but the impact would take another one to one-and-a-half months. Mosquito eggs already laid have developed into larvae, which will continue producing adult mosquitoes.
He added that rainfall creates favourable conditions for Aedes mosquitoes to lay eggs in clean, stagnant water. Current temperatures are still high enough for eggs to hatch.
Entomologist Dr Kabirul Bashar, a professor of zoology at Jahangirnagar University, said dengue infections would likely remain significant throughout November and could continue into December.
He attributed the prolonged season to higher-than-usual temperatures and rainfall.
Dr Tahmina Akter, another professor of zoology at Jahangirnagar University, said increased rainfall could lead to more mosquito breeding, raising the risk of transmission.
Rain forecast raises concerns
The Bangladesh Meteorological Department has forecast possible rainfall in parts of the country over the next five days, although most areas are expected to remain mainly dry.
Its forecast issued on Wednesday said isolated rain or thundershowers could occur in parts of Dhaka, Khulna, Barishal and Chittagong divisions.
Night-time temperatures are also expected to fall slightly.
Experts call for targeted action
Dr Mushtaq stressed that routine cleaning alone would not be enough to control Aedes mosquitoes. Cleaning workers and volunteers should receive practical training to identify and destroy potential breeding grounds in and around homes.
He also called for engaging students and young people in nationwide awareness campaigns to help households identify stagnant water and mosquito breeding sites.
Dr Kabirul Bashar recommended removing accumulated rainwater wherever possible and using larvicides where water cannot be drained.
He also urged the government to ensure adequate dengue testing kits and medical supplies, while preparing hospitals to handle a possible rise in patients.
City corporation measures
Dhaka South City Corporation (DSCC) Administrator Md Abdus Salam said special cleanliness drives had been conducted in every ward following the prime minister's instructions.
He said Saturdays had been designated as Cleaning Day, with residents and government institutions involved in removing waste and cleaning public spaces. Hundreds of truckloads of waste had been removed through the drives, he added.
Acknowledging the risks posed by untimely rainfall, Salam urged residents to prevent water from accumulating around their homes.
He said city corporation cleaning and mosquito-control workers would continue their activities, but public cooperation was essential to make the efforts effective.