The year 2023 is marked by the worst outbreak of dengue since the disease's first official appearance in 2000. The country witnessed 1,705 dengue-related deaths and a total of 321,179 reported cases this year.

In 2000, the nation experienced 93 deaths and 5,551 cases, with the highest recorded death toll before 2023 being 281 in 2022. The highest number of cases before this year was 101,354 in 2019.

In 2023, dengue fatalities saw 970 female and 735 male victims, while in terms of cases, 60 percent were male and 40 percent female. The 36 to 40 age group accounted for 10 percent of the total deaths whereas the 21 to 25 age group led with 14 percent of the reported cases.

Notably, Mugda Medical College and Hospital topped the list with 13,505 cases, while Dhaka Medical College Hospital reported the highest number of deaths -- 253.

One of the main reasons behind dengue deaths this year was second-time infection, while other reasons include late hospitalisation and comorbidity, according to the recent findings of the death review committee of Directorate General of Health Services.

"In our review, we've tried to find the reasons for this year's severity [of the infection]. We found that most of the patients were infected [with dengue] for the second time, which increased the mortality rate," said Prof Ahmedul Kabir, head of the committee and additional director general (administration) of the DGHS.

Experts identified changing patterns of the dengue virus, false results in testing kits, and the presence of serotypes DEN-2 and DEN-3 among other reasons for the staggering number of deaths this year.

HM Nazmul Ahsan, associate professor of Shaheed Suhrawardy Medical College Hospital, said, "This year we got many patients coming to hospital in critical conditions within just a few days of getting infected."

In many cases, he said, test kits give false results. "As a result, patients end up coming to hospital only when their condition is already critical."

"Among the four dengue serotypes, 2 and 3 are most dangerous," he added.

Entomologist GM Saifur Rahman advised the authorities concerned to take necessary steps from the beginning of January to control dengue  in 2024.

The authorities do not seem to be procuring the equipment needed for effective surveillance, he said. "They are rather likely to follow the same old methods that are ineffective," he added.

He pointed out that the data of 2023 does not reflect the real picture because a large number of dengue infections and subsequent deaths go unreported.

A case is recorded only when an individual receives inpatient treatment at one of the 138 hospitals that send information to the DGHS. The rest of the country's around 16,000 facilities do not provide the health directorate with data.

Entomologist Manzur A Chowdhury said, "Without information, it is not possible to kill adult mosquitoes and destroy the larvae in clusters."