El Niño and climate change drive rising dengue outbreak risks

Research published in The Lancet Planetary Health indicates that the El Niño phenomenon and human-induced climate change are significantly increasing the risk of dengue outbreaks. An analysis of over 18 million cases across 21 countries found that a one standard deviation increase in El Niño intensity in the Eastern Pacific is associated with a 23.70% rise in dengue risk.

Human-driven climate change was found to account for 48.64% of the observed increase in outbreaks, representing approximately 403,197 additional infections. These climatic shifts expand the habitat of the Aedes aegypti mosquito by altering temperature, precipitation, and humidity levels.

In Argentina, the National Meteorological Service (SMN) has issued alerts as the warm phase of El Niño is projected to persist through the final quarter of the year. While increased rainfall can create breeding sites, heavy storms can also displace larvae, making the exact epidemiological impact difficult to predict. The severity of the upcoming season will depend on local thermal patterns, rainfall frequency, and preventive measures.