Nearly half of the world’s population is at risk from dengue, a mosquito-borne viral infection which usually hits during monsoon season. According to the World Health Organization the incidence of dengue has increased 30-fold over the last 50 years.

It is now estimated that 50-100 million infections occur annually in over 100 endemic countries. Bangladesh is one such country grappling with the dengue virus, which is bordering on an epidemic.

In the 24 hours from 3pm on July 29 till the same time on Tuesday, some 1,335 patients were admitted to hospitals with the disease, the most admissions on a single day. Almost all the hospitals in the capital Dhaka, a city of some 17 million people, were packed to the brim with dengue patients and doctors have refused to take any more patients.

The dengue outbreak in Bangladesh has been getting worse, spreading among people when an infected Aedes mosquito bites them. The disease has no known cure or vaccine at this point.

According to the Directorate-General of Health Services, the number of dengue cases recorded in the first seven months this year reached a record 15,369 patients with over 13,000 this month. Previously, the number of dengue patients has only passed the 6,000-mark three times in the last two decades: 6,232 in 2002, 6,060 in 2016, and 10,148 in 2018, a DGHS report said.

Dengue first struck Bangladesh in 2000, killing 93 people. Since 2003, the death rate had gradually declined with zero fatalities in some years. However, this year’s outbreak has claimed at least eight lives so far, the official figures reveal.

But after analyzing different media reports, plus data from government and private hospitals in the city, it was however found that the number of deaths caused by dengue this year is at least 35. And the number of districts with dengue cases shot up to 63 today (July 30), the DGHS said.

Explaining the disparity in the number of deaths, officials at the Institute of Epidemiology, Disease Control and Research (IEDCR) said that without collecting blood samples and other information of the deceased to confirm the cause of the death, the government can’t “definitively” declare all these 35 deaths were caused by dengue.

Epidemic or not

ATM Nazrul Islam, deputy director of Dhaka’s Central Hospital, said that people were panic-struck about getting dengue. “It’s not only the cases of dengue that’s alarming. A huge number of people are coming to our hospital with regular fever but suspect that they are suffering from dengue,” he said.

Lutful Ehsan Fatmi, head of the Department of Child Health at Holy Family Hospital of Dhaka, said that his hospital is struggling to tackle the number of dengue patients. “Finding no other options, we needed to open a new section just to tackle the new dengue patients. Certainly, it’s an epidemic,” he said. “A large number of people becoming infected with the same disease at the same time fits the definition of an epidemic.”

However, Dhaka South City Corporation (DSCC) Mayor Sayeed Khokon in a media briefing said the prevalence of dengue in Dhaka could not be called an “epidemic” yet. He said a particular quarter is trying to exaggerate the real situation.

On July 17, the High Court slammed Dhaka’s two city corporations for their failure to curb the mosquito menace in the capital. It said: “Dengue fever has turned into a terrible situation as 21 to 22 people, including children, have reportedly died and hundreds of people have been affected … There is nothing left for the dengue fever to become an epidemic.”

Causes of dengue

The Aedes mosquito, which carries the dengue bug, breeds in clear water and the preferable conditions for it to breed include a subtropical climate and urban or semi-urban landscapes. Dhaka is a megacity that fits the bill. It also has thousands of building sites under-construction, with barrels of stagnant water during the monsoon that become breeding grounds for mosquitoes.

Meanwhile, the mega metro-rail project being built on Dhaka’s main thoroughfare has many sections from the airport to the business hub Motijheel which have been dug and now have stagnant rainwater.

The Aedes mosquito could breed in stagnant water in urban areas during the rainy season, which starts in early May, the DGHS’ Disease Control Director Sanya Tahmina said.

DGHS records show that the great bulk of dengue cases in the country are reported in the capital. Only 1,845 people have been reported with dengue outside the capital since January.

Tahmina said most of the dengue patients outside Dhaka were in the capital when they contacted the virus, but traveled to their ancestral homes afterward. “They have spread the disease there,” she said.

Meanwhile, Permethrin, the main insecticide used by Dhaka’s two city corporations, has proven ineffective against the Aedes mosquitoes, according to a study by the International Center for Diarrheal Disease Research in Bangladesh.

Brigadier General Mominur Rahman, Chief Health Officer of Dhaka North City Corporation, said they were aware of these findings and plan to change the main Permethrin insecticide soon. “We have to go through bureaucratic procedures, the switch is not that easy a process,” Rahman explained.