Spatiotemporal dynamics of cutaneous leishmaniasis in Yucatán, México: retrospective analysis of cases diagnosed between 2015 and 2024
Localized cutaneous leishmaniasis (LCL) is a vector-borne disease endemic to southeastern México. Although the number of LCL cases has increased in Yucatán since 2015, detailed analyses of its epidemiological characteristics and spatiotemporal dynamics remain limited. A retrospective analysis of confirmed leishmaniasis cases reported in Yucatán from 2015 to 2024 was conducted using the state's nominal surveillance database. Incidence rates were estimated using population data from CONAPO (Consejo Nacional de Población), and spatiotemporal clusters were identified using Kulldorff's scan statistics under a discrete Poisson model. A total of 401 cases were recorded, of which 34.7% were autochthonous. The disease predominantly affected adult males engaged in agricultural activities. The mean annual incidence was 0.60 cases per 100,000 inhabitants (95% CI: 0.14-1.07), increasing to 3.1 (95% CI: 2.56-3.59) when restricted to populations at risk in municipalities with active transmission. Autochthonous cases were detected in 18 municipalities, 13 without prior records, suggesting geographic expansion of local transmission. Three significant spatiotemporal clusters were identified, revealing distinct transmission dynamics across the state. Two were classified as emerging clusters: an early cluster in the eastern region in 2015 (RR = 80.05), suggesting an initial outbreak, and a major cluster in the northeastern region active between 2022 and 2024 (RR = 59.84), indicating recent intensification of local transmission. A recurrent cluster in the southwestern region (2022-2023; RR = 19.44) was detected, suggesting persistence of transmission in historically affected areas. These findings indicate an ongoing epidemiological transition of LCL in Yucatán, characterized by emerging foci and spatial heterogeneity, highlighting the need for strengthened surveillance and targeted prevention strategies in high-risk areas.