A BSC-led study combines climate and virus surveillance to predict dengue outbreak risk in Singapore

Dengue outbreaks are becoming increasingly common and explosive across the world, posing a major public health challenge in regions such as Southeast Asia. Rising global temperatures and changes in rainfall patterns under climate change have accelerated the spread of dengue, with 2024 witnessing a historic peak of 14 million dengue cases reported globally alongside the warmest year on record. Early warning systems incorporating climate information offer the potential to mitigate the impact of dengue outbreaks and inform public health response.

In this direction, a new study led by researchers from the London School of Hygiene and Tropical Medicine (LSTHM) and the Barcelona Supercomputing Center-Centro Nacional de Supercomputación (BSC-CNS), and developed in collaboration with Singapore’s National Environmental Agency, presents a forecasting model that captures the complex interplay between climate and changes in circulating dengue viruses to predict dengue outbreak risk in Singapore.

Singapore’s National Environment Agency has pioneered the use of information on the prevalence of the four dengue serotypes, i.e. the four mosquito-borne dengue viruses that can cause disease, to understand dengue transmission patterns. This new research, now published in the journal Nature Communications, showed that incorporating information about different dengue serotypes enhanced the predictive ability of the forecasting model beyond climate data alone. 

“By combining climate information with disease surveillance, advanced modelling and high-performance computing, we can better understand how climate variability influences dengue dynamics. This integrated approach allows us to anticipate outbreaks weeks in advance and provide actionable early warnings that support public health decision-making in a changing climate,” said Rachel Lowe, ICREA Professor, leader of the GHR group at the Earth Sciences Department of BSC and Visiting Professor at the National University of Singapore’s Saw Swee Hock School of Public Health.

Emilie Finch, the first author and a researcher at LSTHM at the time of the study, explained: “Using over 20 years of data, we have shown that the risk of a dengue outbreak is highest during El Niño conditions and in the first few years following a change in the dominant dengue serotype circulating in the population.” Currently, Dr Finch has a postdoctoral position at the Pathogen Dynamics Unit in the Department of Genetics at the University of Cambridge and is a visiting researcher at the BSC’s Global Health Resilience group.

The authors also used Singapore’s National Environment Agency’s model to estimate the impact of releases of Wolbachia-carrying mosquitoes (Project Wolbachia) on dengue transmission. Since 2016, Singapore’s National Environment Agency has been trialling a novel suppression strategy where male mosquitoes carrying Wolbachia—a bacterium found naturally in many insect species—are released to suppress the mosquito population in the community and reduce dengue transmission. Using their modelling approach, the research team estimated that around 28% of dengue cases expected in 2023 were averted due to expanded Project Wolbachia releases in 2022.

"This prediction model, which captures complex climate and virus circulation patterns, is novel and will be a valuable addition to the National Environment Agency's repertoire of tools for risk assessment that informs decision-making in our continuous efforts to protect public health,” stated Associate Professor Ng Lee Ching, Group Director at the Environmental Health Institute of Singapore’s National Environment Agency and faculty at the NUS’s Saw Swee Hock School of Public Health.

Looking ahead, the research team plans to compare the performance of this model with other dengue forecast modelsand explore how it could be applied to other geographic contexts. This work demonstrates how interdisciplinary collaboration across computational modelling, climate science and public health can help to mitigate disease outbreaks in an era where rapid climate change is leading to unprecedented extreme events.