Morbidity and Mortality Profile of Leishmaniasis in an Andean Region of Ecuador in the Context of Climate Change.

Leishmaniasis is a parasitic disease transmitted by female sandflies of the genus Lutzomyia. Ecuador is divided into three distinct natural regions: the Andes, the Coast, and Amazonia, each characterized by significant variations in altitude and climate. While most reported cases of leishmaniasis are associated with humid, low-altitude rural areas, our study uncovered an unexpected trend: confirmed cases occurring in traditionally cold Andean regions. To investigate this issue, we conducted a cross-sectional ecological study using official morbidity and mortality records from the Ecuadorian Health Care Registration Platform, focusing on the cantons of Alausí and Chunchi in Chimborazo Province from 2013 to 2022. Chimborazo Province, in the Andes, is characterized by higher altitudes (2740 m above sea level) and a cold climate (averaging 13 °C throughout the year). Among a population of 44,089 residents in Alausí, we reported a total of 40 confirmed cases, with 97.5% classified as cutaneous and 2.5% as mucocutaneous, predominantly affecting children and males. No mortality cases were recorded during the study period. To further explore environmental influences, we examined the Alausí region, where climate change has led to rising average temperatures, deforestation, and changes in humidity levels. Leishmaniasis cases in Alausí showed seasonal peaks, particularly in 2018 and 2019, correlating with warmer and more humid conditions. Environmental factors such as temperature and humidity were strongly associated with the prevalence of the disease, suggesting that climate change may be increasing transmission risks. These findings point to the value of incorporating environmental monitoring into public health strategies for vector-borne diseases that affect vulnerable populations in the Andes.