A new study has revealed that climate change is responsible for nearly 20% of the record-breaking dengue cases reported worldwide in 2024.
The findings, presented at the American Society of Tropical Medicine and Hygiene’s annual meeting in New Orleans, highlight how rising temperatures are enabling dengue-carrying mosquitoes to invade previously cooler regions.
“Dengue is a very climate-sensitive disease, making it an important indicator of the health impacts of global warming,” said Erin Mordecai, an infectious disease ecologist at Stanford University and the study’s senior author.
The mosquito-borne virus, which causes fever, severe body pain, and, in extreme cases, death, thrives in temperatures between 20°C and 29°C.
As global temperatures rise, the habitats of dengue-carrying mosquitoes have expanded, driving unprecedented outbreaks across Asia and the Americas.
The study analyzed data from 21 countries, finding that 19% of current dengue cases can be traced to past climate warming.
Elevated areas in Peru, Mexico, Brazil, and Bolivia were identified as hotspots, with projections indicating dengue cases in these regions could increase by up to 200% within 25 years.
Globally, approximately 257 million people now live in areas where climate change could double dengue transmission rates by 2050.
The World Health Organization (WHO) has reported 12.7 million dengue cases as of September 2024—nearly double the record set in 2023—though researchers believe the true figure could exceed 100 million due to widespread under-reporting.
Amid the alarming statistics, there is promising news.
Another study presented at the conference demonstrated the effectiveness of Wolbachia-infected mosquitoes, which are genetically modified to block dengue transmission.
In Niteroi, Brazil, where these mosquitoes were introduced five years ago, dengue cases remain 90% lower than before the intervention, even during Brazil’s worst dengue outbreak on record this year.
Inspired by this success, researchers are collaborating with the Brazilian government to build a large-scale facility to produce Wolbachia-infected mosquitoes, aiming to shield millions from future outbreaks.