In Bangladesh’s public health sector, what was once a seasonal concern confined largely to Dhaka has mutated into a year-round, nationwide crisis. Driven by unplanned urban expansion, shifting climate patterns, and dynamic serotype shifts—that is, changes in the circulating strains of the dengue virus—Aedes aegypti, or the “dengue mosquito,” has extended its reach across the country.
The catastrophic 2023 outbreak saw 3,21,179 reported cases and 1,705 deaths, exposing systemic vulnerabilities in vector control. This year, 58 districts have already reported cases, with Barishal, Chattogram, and Khulna bearing burdens close to Dhaka’s. As per the national dengue dashboard, this year up until August 16, a total of 23,978 cases have been detected, 805 patients have been hospitalised, and 70 people have died of dengue. Yet our national response remains Dhaka-centric and reactive.
Four structural gaps have hampered this response: i) vector control intensifies only after hospital wards overflow, not year-round; ii) responsibility is split across city corporations, the Directorate General of Health Services (DGHS), and local government institutes with no single accountable body; iii) resources remain centralised, leaving district and upazila complexes ill-equipped to deal with surges; and iv) for over two decades the country has relied almost exclusively on chemical fogging and temephos larvicide (a chemical used to treat stagnant water and kill mosquitoes), methods to which mosquitoes have grown resistant.
Bangladesh must move beyond fragmented reactions and adopt a comprehensive framework integrating vector management, community empowerment, local research, international cooperation, and a vaccine strategy.
Effective vector control requires an Integrated Vector Management (IVM) approach targeting every phase of the Aedes life cycle: egg, larva, pupa, adult, and host. Modern smart IoT-Ovitraps, using AI image recognition, count eggs in under three seconds with over 95 percent accuracy, streaming real-time data to a central dashboard. A primary surveillance network of roughly 400 to 650 traps across high-risk municipality wards could provide an early-warning feed, allowing municipal teams to target larviciding weeks before cases emerge. Transitioning from chemical larvicides to Bacillus thuringiensis israelensis (Bti)—a naturally occurring soil bacterium—offers safe biological control that damages the gut of mosquito larvae when they ingest it, without harming non-target organisms or inducing resistance among mosquitoes.
Thermal fogging offers only short-lived knockdown of adult mosquitoes while scattering vectors indoors. Sustainable adult control instead requires interventions such as the Wolbachia method, in which mosquitoes carrying the natural Wolbachia bacterium block dengue virus replication, and as they mate with wild populations, the Wolbachia trait spreads, permanently suppressing transmission. In Yogyakarta city of Indonesia, this method cut dengue incidence by 77 percent and hospitalisation by 86 percent.
While vector control reduces mosquito density, protecting populations at scale requires vaccination within national immunisation pathways. A milestone in global dengue control was the clearance of Qdenga (TAK-003), Japanese company Takeda’s live-attenuated tetravalent vaccine, designed to protect against four different strains of dengue. It is now approved for ages 4 to 60 in over 40 countries, including India, countries in the EU, and Brazil. Besides, the World Health Organization (WHO) recommends its use “in children aged 6-16 years in settings with high dengue transmission intensity.”
Earlier candidates like Dengvaxia required costly pre-vaccination screening, since seronegative recipients—people with no antibodies against dengue in their blood—were at increased risk of severe dengue; Qdenga requires no screening. Phase-3 data from the Tetravalent Immunization against Dengue Efficacy Study (TIDES), involving over 28,000 participants, showed robust immune memory against all four serotypes; roughly 84 percent protection against hospitalisation and about 61 percent against symptomatic infection; and safety regardless of prior exposure status.
In Bangladesh, vaccination should be a high-payoff layer within our IVM framework, not a standalone fix. Brazil, the first nation to include Qdenga in its free healthcare system, saw a significant drop in infections in targeted pilots. Bangladesh’s Ministry of Health and Family Welfare should begin consultations with WHO and its Strategic Advisory Group of Experts on Immunization (SAGE) on cost-benefit dynamics. Phased pilots should target school-aged children and frontline workers in endemic hotspots before a national rollout; and the government should pursue manufacturing partnerships, similar to Takeda’s deal with India’s Biological E, to secure affordable doses.
Reducing mortality also hinges on early diagnosis. The government deserves recognition for eliminating financial barriers by making one of the three blood tests for dengue free while capping the other two at Tk 50. Last month, rapid NS1 antigen testing was made free across upazila complexes, district hospitals, and tertiary centres until December 31, enabling detection during the critical first five febrile days when the patient has a high fever. Last year, the interim government had capped NS1 as well as serological IgM/IgG fees at Tk 50 at public labs.
However, testing must also reach community touchpoints. Trained NS1 stations in pharmacies, schools, and Export Processing Zones can screen garment workers and schoolchildren at first fever. Meanwhile, personal repellent use remains the single immediate action individuals can take. Since repellents containing DEET, Icaridin, or IR3535 disrupt mosquito host-seeking, these should be distributed among people, prioritising pregnant women, young children, and informal workers.
Bangladesh must also become a regional leader in vector-borne disease research. Genomic sequencing would flag serotype shifts early, since displacement often precedes surges in severe infections. Also, to ensure that funds are only used for larvicides that remain effective, resistance mapping across all 64 districts must be done. Collaborative research between the icddr,b, Bangladesh Medical University, and university labs, alongside partnerships with institutions such as Brazil’s Fiocruz, a prominent institution of science and technology in health in Latin America, could fast-track capabilities.
None of this is achievable without dedicated governance and financing. A national dengue task force reporting directly to the Prime Minister’s Office would create a single point of command, holding budgetary authority over vector control and streamlining coordination among the DGHS, city corporations, and local government. The government should also remove tariffs on repellents, larvicides, and diagnostic components, pairing tax cuts with price monitoring to keep protection affordable for low-income households.
Legal enforcement matters just as much as fiscal relief. Clean-premises obligations backed by mobile courts should hold sites with unmanaged stagnant water liable to fines, thus institutionalising source reduction as a civic obligation. Every dengue fatality should undergo mandatory review within 48 hours, examining late presentation, diagnostic delay, or blood scarcity and thus creating a feedback loop that lets administrators fix bottlenecks immediately.
Dengue is no longer an unpredictable natural disaster. It is a complex, ecological, urban health challenge manageable through science, policy, and organised governance. By bringing together IVM, forward-looking vaccine deployment, affordable diagnostics, robust research, and decisive policy action, Bangladesh can permanently alter its epidemiological trajectory.
Dr Sayem Mohammad a clinician scientist and policy activist, is associate professor of medicine at Holy Family Red Crescent Medical College Hospital (HFRCMCH) and chief organizer at Stakeholders of Bangladesh.
Views expressed in this article are the author's own.
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