Hanoi (VNA) – Vietnam's health authorities are warning of increasingly complex dengue fever developments as infections surge, outbreak cycles become shorter and traditional seasonal patterns begin to shift, prompting calls for heightened vigilance and stronger disease prevention efforts.
According to the Ministry of Health (MoH), more than 50,000 dengue cases and five related deaths have been recorded nationwide since the beginning of the year, a 2.5-fold increase compared to the same period in 2025. The sharp rise suggests that outbreaks are occurring earlier and becoming harder to forecast.
Vo Hai Son, Deputy Director of the ministry's Administration of Disease Prevention, said dengue fever is no longer following previous epidemiological trends. In 2025, infections remained elevated through November and December rather than declining at the end of the year as had traditionally been the case, indicating a shortening outbreak cycle.
Weather conditions have also contributed to the spread of the disease. Extended periods of heat, humidity and rainfall have created favourable breeding conditions for mosquitoes, while the dominance of the DENV-2 serotype has been linked to a growing number of severe cases and hospital admissions.
Hanoi remains among the localities facing heightened risks due to its large population and rapid urbanisation. Since the beginning of 2026, the capital has recorded 337 cases across 93 wards and communes, higher than the figure reported during the same period last year. Although no major outbreaks have been identified, local health authorities have warned that case numbers could continue to rise and are maintaining close monitoring in affected areas.
Tran Nhu Duong, Deputy Director of the National Institute of Hygiene and Epidemiology, said an effective response depends on a three-pronged approach comprising enhanced surveillance and technical support from the health sector, active engagement by local authorities and stronger public awareness of prevention measures.
Meanwhile, Dao Huu Than, Deputy Director of the Hanoi Centre for Disease Control, emphasised that eliminating mosquitoes and larvae at household level remains the most practical and sustainable way to reduce transmission risks.
As dengue outbreaks become increasingly unpredictable and the risk of severe reinfection grows, health experts believe scientific and technological advances can strengthen prevention efforts. Angela Pratt, Representative of the World Health Organisation (WHO) in Vietnam, said the country has approved a dengue vaccine and is preparing pilot programmes to evaluate its effectiveness and feasibility before considering its inclusion in the national Expanded Programme on Immunisation.
However, health authorities stressed that vaccines and AI-powered early warning systems should be viewed as complementary tools rather than substitutes for traditional mosquito control measures.
Under the slogan “No larvae, no dengue”, the MoH has urged residents to regularly remove mosquito breeding sites, keep water containers covered, sleep under mosquito nets and seek prompt medical attention if a fever lasts more than two days, instead of attempting self-treatment at home./.
