Proceedings of the inaugural symposium on dengue human challenge studies “Challenging the norm: Accelerating dengue countermeasures through human studies”

On 12th June 2025, Duke-NUS Medical School, supported by the Global Dengue and Aedes-Transmitted Diseases Consortium (GDAC), hosted a one-day symposium in Singapore titled "Challenging the norm: Accelerating dengue countermeasures through human challenge studies". Comprising sessions on both dengue and other viral infection models, the symposium explored how human challenge studies could address gaps in dengue pathogenesis and immunity to inform vaccine development and application. Keynote speakers highlighted persistent challenges in dengue vaccine development, including incomplete protection across all four dengue viruses, complexities in dengue immunity, and past safety concerns that have influenced regulatory pathways. Case studies from Thailand and Bangladesh illustrated the feasibility and safety of dengue challenge studies in endemic settings. Parallel discussions drew lessons from human infection models of SARS-CoV-2 and other respiratory viruses that are directly relevant to expanding the use of dengue human challenge studies. Sessions on public engagement and regulatory frameworks emphasised the importance of trust, transparent communication, and harmonisation in the design, conduct, and acceptance of challenge studies. Overall, the symposium highlighted that human challenge studies, if implemented thoughtfully, can advance dengue vaccine research, accelerate clinical evaluation and regulatory approval of vaccine candidates, and support evidence-based public health strategies to strengthen global dengue control efforts.