Dengue vaccine shows favorable safety profile in travellers from non-endemic regions,reports research

Data from 1,028 people vaccinated with TAK-003 in Catalonia suggests that the dengue vaccine has a good tolerability profile in routine clinical practice among travellers from regions where dengue is not endemic. The findings come from a study led by the Barcelona Institute for Global Health (ISGlobal), a centre supported by ”la Caixa” Foundation, together with Hospital Clínic Barcelona, and recently published in The Lancet Regional Health Europe. Participant follow-up revealed no serious adverse events, whilst reported reactions were mostly mild or moderate and less frequent after the second dose.

Dengue is a viral disease transmitted by Aedes mosquitoes. Transmission has been documented in more than 100 countries, and more than half of the world’s population is estimated to live in areas at risk of infection. In recent decades, dengue incidence has increased due to the geographical spread of mosquito vectors, driven in part by climate change, as well as the rise in international travel, which contributes to the global circulation of the virus. Dengue has also become one of the leading causes of fever among people travelling to endemic regions. In this context, a safe dengue vaccine is essential to protect people at risk and to inform effective public health strategies.

Limited evidence on vaccine safety in travellers

TAK-003 is the first vaccine authorised in Europe to protect against the dengue virus. However, data on its safety in people who do not live in endemic areas remains limited, particularly among certain groups such as older adults, people with pre-existing medical conditions, and those receiving additional vaccines.

“To help address this knowledge gap, we conducted a pharmacovigilance study across eight travel health centres in Catalonia,” explains Daniel Camprubí-Ferrer, first author of the study, ISGlobal researcher and member of the International Health Service at Hospital Clínic Barcelona. The study included 1,028 travellers, mostly adults, who received TAK-003 between January and December 2024. After each dose, participants were followed up to record any adverse effects.

“We also wanted to assess whether factors such as age, sex, previous dengue infection or the co-administration of other vaccines were associated with a higher risk of adverse effects, both local and systemic,” adds Camprubí.

No serious adverse events observed

The study recorded no serious adverse events following the administration of 1,851 TAK-003 doses. Although more than half of participants reported some type of adverse effect, these were mostly mild or moderate, temporary, and less frequent after the second dose. The most common symptoms were pain at the injection site, headache, fatigue and general malaise.

Women and people with previous dengue infection, more likely to experience adverse effects

The analysis found that female participants, people with a previous dengue infection, and those who received concomitant vaccines against other flaviviruses (such as the yellow fever vaccine) had a higher risk of adverse events. Among women, reactions were mainly local, whereas in the other two groups they were predominantly systemic, such as fever.

“Importantly, we did not observe increased reactogenicity in people over 60 years of age or in those with comorbidities, two groups for which evidence has so far been very limited,” explains Cesc Bertran-Cobo, ISGlobal researcher and one of the study authors. The study also found no increased likelihood of adverse events when the dengue vaccine was administered at the same time as non-flaviviral vaccines, supporting its use in pre-travel consultations.

“Our findings expand the available evidence on the safety of TAK-003 in European travellers and highlight the need to continue assessing its impact, effectiveness and long-term safety,” concludes Jose Muñoz, ISGlobal researcher and head of the International Health Service at Hospital Clínic Barcelona.

Reference:

Camprubí–Ferrer D, Bertran–Cobo C, Valerio L et al., Safety of the Dengue Vaccine TAK-003 and Factors Associated with Adverse Events in Travellers from Non-Endemic Areas: A Real-World Prospective Multicentre Pharmacovigilance Cohort Study in Spain, The Lancet Regional Health – Europe, DOI: 10.1016/j.lanepe.2026.101727