Dengue and Aedes aegypti expansion into high-altitude areas of Latin America: A scoping review

Background The geographic distribution of Aedes aegypti and dengue virus (DENV) is expanding into high-altitude, historically non-endemic ecosystems across Latin America. This scoping review synthesizes evidence on the ecological limits, thermal thresholds, and socio-environmental drivers that govern this altitudinal expansion. Methods Following Joanna Briggs Institute (JBI) methodology and PRISMA-ScR guidelines, a systematic search was conducted across PubMed, Scopus, LILACS, and Web of Science through February 2026. Evidence was extracted from 28 eligible studies evaluating vector establishment, viral circulation, and environmental predictors across elevation gradients. Results Synthesis confirms that Ae. aegypti has breached the historical ecological barrier of 1,500 meters above sea level (m.a.s.l.). Larval infestation and autochthonous viral transmission are documented above 2,000 m.a.s.l., reaching established limits of 2,550 m.a.s.l., with oviposition recorded up to 2,900 m.a.s.l. Colonization is driven by thermal anomalies linked to El Niño-Southern Oscillation (ENSO) events, coupled with rapid urbanization and intermittent municipal water supply. Conclusions Topographies below 2,500 m.a.s.l. no longer provide natural insulation against vector establishment. Public health frameworks must transition toward predictive microclimatic vector surveillance in mountain communities.