DHAKA: Bangladesh is facing its worst dengue fever outbreak on record, with the annual death toll reaching 1,606, according to official figures released on Monday.

Dengue is a recurrent health risk during the monsoon season, which normally runs from July to September. According to the Directorate General of Health Services, so far this year, more than 309,000 people have been infected with the virus, which is transmitted by Aedes mosquitoes that breed in freshwater pools and drains.

The death toll is the highest since records began in 2000 and almost six times the 281 fatalities recorded last year.

Health experts have expressed concern at the length of this year’s outbreak, as the number of dengue infections usually subsides as the monsoon rains end. But the country has recorded nearly 38,000 cases in November alone.

“Despite the decreasing number of patients now, we did not record any dengue patients in this period in previous years,” Md. Sharfuddin Ahmed, vice chancellor at the Bangabandhu Sheikh Mujib Medical University in Dhaka, told Arab News.

And while previous outbreaks have tended to be confined to heavily populated urban areas, like the capital Dhaka, which is home to more than 23 million people, this year they have been reported far and wide, including in rural areas.

“This year the dengue outbreak was recorded across the country, which didn’t happen in previous years,” Ahmed said.

More than 65 percent of the cases reported this year were from outside Dhaka, the first time the city has not accounted for the majority of infections, the figures showed.

“Considering the overall situation, the management of dengue is a bit problematic in our country. If people went to the doctor on time and received early treatment, we could minimize the number of deaths,” Ahmed said.

Muzaherul Huq, a public health expert and former regional adviser for the World Health Organization, said the extended dengue season was likely linked to climate change, which has resulted in rising temperatures and longer monsoon seasons.

“Dengue season shouldn’t continue for such a long period,” he told Arab News.

The Bangladeshi government needed to “strengthen the dengue control mechanism” ahead of future outbreaks and involve the public in the process, both by raising awareness and controlling dengue-carrying mosquitoes, he said.

And with recent reports suggesting a change in disease patterns, there was also a need for more research, he said.

“We need to have further research to comply with the reported disease pattern changes of dengue.”