New york: Dengue fever outbreaks in the Americas tend to occur about five months after an El Nino event, according to a new study published Thursday in Science Translational Medicine. The research highlights clearer links between the mosquito-borne disease and climatic conditions in a region that recorded a record 13 million cases in 2024.

According to Anadolu Agency, the study analyzed nearly three decades of data from 14 countries. Researchers found that cases across the region rose and fell in sync, about six months apart, even between areas as distant as 10,000 kilometers (6,213 miles).

The findings are 'useful to anticipate when a region might expect to see an epidemic, which can help inform planning and preparedness,' said co-author Talia Quandelacy, an infectious-disease epidemiologist at the University of Colorado School of Public Health. Quandelacy noted that the connection between dengue and climate has long been known, but the study shows how that relationship plays out across the entire continent.

She explained that the dengue virus replicates faster in warmer conditions, and the incubation period of dengue viruses in the mosquito shortens at high temperatures, leading to more-efficient transmission of the virus.

Still, the climate is only part of the picture. Population immunity and poor sanitation in urban areas also play a role, said Marcia Castro, a public-health specialist at Harvard T.H. Chan School of Public Health. Castro emphasized that while analyses showing the impact of extreme weather events like El Nino are important, local characteristics of urban areas need to be considered.