In February 2019, leading international medical journal The Lancet reported in its news section that a spike in the number of cases of dengue, the mosquito-borne tropical disease that is now established as a seasonal epidemic in Bangladesh, was set to continue in Bangladesh, as well as in other south and south-east Asian countries such as India, Myanmar, Cambodia and others.

The report, "Dengue rises in Bangladesh" by Sophie Cousins noted that 2018 had not only seen an explosion in the number of recorded dengue cases- more than triple the number of cases recorded in 2017-but also "a lengthening of its season." Some 9926 confirmed cases of dengue occurred in Bangladesh in 2018, an increase from 2769 in the previous year, according to data from the Institute of Epidemiology Disease Control and Research. (The Directorate General for Health Services counted 10,148). There were 17 deaths, making it the deadliest year since the first recorded epidemic in 2000, when 93 people died.

The report pointed to unplanned rapid urbanisation and a "construction boom in the capital" as problems allowing dengue to thrive. "Across the city, high-rise apartment blocks, hotels, and malls are being built, but with the hasty development have come barrels of stagnant water- perfect breeding grounds for the Aedes aegypti mosquito," it said. For almost any resident of the capital, that picture would resonate.

As far back as the time of the report in The Lancet, the efficacy of the insecticide being used by the city corporations was being questioned. And yet even as the number of cases kept breaking all records last week, we had to learn from the lawyers for Dhaka's two city corporations that "at least one month's time is needed to import new medicine for resisting the mosquito menace." At least.

The lawyers were appearing before a bench of the High Court in response to a July 22 ruling that summoned the chief health officers of the Dhaka north and south city corporations to appear before it and inform the court about the steps taken by the corporations to prevent any outbreak of mosquito-borne diseases like dengue and chikungunya, and to destroy the breeding grounds of Aedes mosquitoes in the capital. The court, however, exonerated the chief health officers of the city corporations from personal appearance before the court, and so the lawyers represented them.

At one point, the High Court expressed great concern at the outbreak of dengue fever and wanted to know how the effective medicine (insecticide) for preventing the genus of the mosquito that spreads the virus from proliferating could be imported within seven days, having learned that the current stock of insecticide kept by the city corporations was useless. It was then that the lawyers asked for the "at least one month" timeframe from the court, and laughably, prayed to the court to allow "three or four days" to see the results of a so-called "crash program" with the existing medicine and some combined operation for solving the mosquito problem. At no time did they inspire confidence.

A week or so on from the hearing, things have gotten considerably more alarming. When the summons was issued, around 400 new patients were being admitted in hospitals around the country daily with confirmed cases of dengue infection. It rose to over 550 by the time their lawyers appeared on July 25. On July 27, the number of new patients admitted was 683. The next day it broke the 800-mark. By the 29th, 1,096 new dengue cases were being reported in a single day, and the next day, it rose above 1300, bringing the total number affected for the year to 15,369 as of July 30, according to the Directorate General for Health Services. Along the way, last year's record had been smashed before August, which is usually the most dangerous month. The DGHS numbers also showed that the number of districts with dengue cases had shot up to 61, out of the 64. Less than a week ago it was 22.

When it comes to the number of fatalities, the government's figures are extremely slow to catch up to reality, since the Institute of Epidemiology Disease Control And Research or IEDCR, that maintains it only updates its number after "exhaustive scrutiny" of each case to determine whether the death was indeed caused by dengue. As such, the official figure as Dhaka Courier went to press this week stood at just 8, when non-official sources are counting between 30-35.

Swatting a life

U Khein Nu, was a first-year undergraduate pharmacy department student of the Jahangirnagar University's 48th batch. Hailing from Cox's Bazar, as an only child she was the apple of her parents' eyes. Father Mong Ba Ang Mong Ba headed the local government desk at the district administration office, and was also renowned locally as a researcher and author, while mother Ma Ching worked for the local branch of Janata Bank.

In their Anderson Road neighbourhood, U Khein was known for being a meritorious student, having achieved outstanding results in her JSC, SSC, and HSC exams. When she gained admission to study pharmacy at JU, it came as no surprise to them. Little did they know how her dreams would be shattered, by something as random and mundane as a mosquito bite.

U Khein was first admitted to the JU Medical Centre, who referred her on to Enam Medical College Hospital in Savar, near her university, when she fell ill on July 17. She was subsequently released on July 20 and her parents took her home to Cox's Bazar. As the fever returned with tremendous pain - the kind that gives dengue its other name, 'breakbone fever' - on July 26, her parents had her admitted to Cox's Bazar Sadar Hospital, from where she was referred to the Chittagong Medical College Hospital the next day. But they failed to make it, as U Khein breathed her last in the ambulance carrying her near Lohagora, while on the way to CMCH. She was just 19. According to the Dainik Azadi, a Chittagong-based daily, U Khein's is the first known case of a death from dengue in Cox's Bazar.

Visiting different hospitals, our sister newsagency UNB's correspondents found doctors struggling to handle the rising number of dengue patients and huge numbers of people with fever rushing to hospitals for dengue test. Sales of anti-mosquito sprays and mosquito nets have been on the rise as panic gripped the city dwellers following the outbreak of the deadly disease.

Shakhawat Hossain, a media worker, found his nine-year-old son suffering from fever when he went home after office on the night of July 18. The fever turned severe overnight. A doctor suggested he admit his son to a hospital immediately as he was found infected by dengue next morning and then the struggle began, Shakhawat narrated. Most hospitals lacked empty beds but somehow Shakhawat managed one at a government hospital.

Saleh Uddin Jinnah, a teacher by profession from Thakurgaon, sent his son Mukul to a private university for higher education in the capital. On June 24, Jinnah got worried hearing that his son was lying senseless at his university hostel and rushed to the capital immediately. In the meantime, Mukul's friends admitted him to a government hospital.

"Tension, blood collection hazards and hospital expenses made me mad at the time," he said.

Although Shakhawat Hossain's son and Mukul both survived, their stories demonstrate the mental toll it takes on care-givers as well, just to look after someone with dengue, apart from the suffering undergone by the victims themselves.

An enemy entrenched

The dengue virus comes in four varieties. All are spread by female Aedes mosquitoes, primarily Aedes aegypti, with a penchant for sucking blood during the day, when individuals are unprotected by bed nets. In the past five decades these viruses, which are related to those that cause West Nile fever, yellow fever and Zika, have spread in waves across the tropical and subtropical world, increasing dengue incidence 30-fold globally over the past five decades. According to the World Health Organisation, some 50 to 100 million new infections are estimated to occur annually in more than 100 endemic countries.

How come you don't see these tens of millions? Well, that is because of a peculiar property whereby not everyone infected with a dengue virus gets sick: in fact, three out of four who get bitten will have no symptoms, according to Seema Yasmin and Madhusree Mukherjee, writing in Scientific American. The rest may suffer one of three sets of symptoms: a fever that mimics many other viral illnesses; "dengue fever," which is accompanied by headache, pain behind the eyes, aching joints and bones, and, in rare cases, internal bleeding; and severe disease encompassing dengue hemorrhagic fever and dengue shock syndrome. In severe cases, plasma seeps out of capillaries, liquid pools around organs, massive internal bleeding ensues, and the brain, kidneys and liver begin to fail. Although swift hospitalization and careful case management can and do save lives, more than 20,000 people die of dengue every year, according to WHO.

So it would be wrong to think that the authorities in Bangladesh are alone in struggling to cope with the dengue menace. The list is long, and includes all sorts. Over in Central America, the Honduras is dealing with its worst dengue outbreak in 50 years - with over 28,000 affected till July 26. Closer to home, the Philippines declared a national dengue alert this month after a spike in cases this year. Around 100,000 dengue cases were reported across the country in the first six months of 2019, killing an incredible 456 people till July 16. Between Jan. 1 and July 29, Vietnam spotted over 105,000 dengue fever patients, more than trebling the cases in the same period last year. Singapore's Ministry of Health (MOH) reported that there were 8,020 dengue cases reported to MOH as of July 20. That is about five times more than the total number of dengue cases reported in the same period last year. All of these numbers are from the respective governments.

Additionally, the WHO reports spikes have been observed in Australia, Cambodia, China, Lao PDR, and Malaysia, while outbreaks have also been reported in Congo, Côte d'Ivoire and Tanzania in the African region, alongside several countries of the American region.

Given all this, you can understand why health practitioners in developing countries have been eagerly awaiting a vaccine for decades. Around four years ago, high hopes centred the development of Dengvaxia, the first approved vaccine against dengue that was licensed in 19 countries including Bangladesh. Before the developer Sanofi Pasteur -the vaccine division of French pharmaceutical giant Sanofi S.A- could bring it to market in all those countries however, some shortcomings and in fact outright dangerous findings showed up upon further scrutiny. It is now classed as a "partially effective" vaccine available commercially in 11 countries: Mexico, the Philippines, Indonesia, Brazil, El Salvador, Costa Rica, Paraguay, Guatemala, Peru, Thailand, and Singapore.

The WHO's current position on Dengvaxia states that it has "been shown in clinical trials to be efficacious and safe in persons who have had a previous dengue virus infection (seropositive individuals), but carries an increased risk of severe dengue in those who experience their first natural dengue infection after vaccination (seronegative individuals)." The WHO goes on to state, for countries considering vaccination as part of their dengue control programme, that "pre-vaccination screening is the recommended strategy". With this strategy, only persons with evidence of a past dengue infection would be vaccinated (based on an antibody test, or on a documented laboratory confirmed dengue infection in the past).

Researchers at the Institute Pasteur, in collaboration with teams at Johns Hopkins University, ICDDR,B and the IECDR, carried out a seroprevalence study (to detect dengue antibodies that individuals develop once infected, even when they haven't developed symptoms) visiting 70 different communities all over Bangladesh. From their measurements it was estimated that an average of 2.4 million people are infected with dengue each year in Bangladesh. Their results were published in May.

The track record of dengue reveals that it enters a country not to leave. In countries where dengue has emerged as a public health problem, it has remained so, proving thereby that it is not merely a clinical issue. Vector control aimed at the population of Aedes aegypti can only go so far. Given the extent of the epidemic this year, not only in terms of the numbers infected but also the geographical distribution, the country may be faced with a reckoning sooner rather than later, on a new strategy to deal with an old enemy.