Spatiotemporal analysis of cutaneous and visceral leishmaniasis in Brazil, 2003 to 2022

Cutaneous (CL) and visceral leishmaniasis (VL) are epidemiologically relevant diseases in Brazil.

The aim of this study was to describe the occurrence of cutaneous CL and VL and to identify spatiotemporal clusters in Brazilian municipalities between 2003 and 2022.

This descriptive ecological study was conducted using data on new CL and VL cases reported to the Notifiable Diseases Information System. Incidence rates were calculated by sex, age group, macro-region, and biome. To identify high-risk spatiotemporal clusters, Poisson scan statistics were used. Socioeconomic (Municipal Human Development Index - MHDI), environmental (vegetation cover, deforestation, temperature), and climatic variables were compared between high and low-risk municipalities using Student's t-test.

The incidence of CL was 9.72 cases/100,000 person-years, with the highest rates in the North region, the Amazon and Pantanal biomes, and among males aged 15-49 years. For VL, the incidence was 1.39 cases/100,000 person-years, with emphasis on the North, Northeast, and Midwest regions, particularly in the Pantanal biome, and among children aged 0-9 years. High-risk spatiotemporal clusters for CL were identified in the North, Northeast, and Midwest regions between 2003 and 2012. For VL, spatial clusters occurred in the North, Northeast, Midwest, and Southeast regions, with a temporal cluster between 2004 and 2011. Compared to low-risk areas, municipalities in high-risk clusters for both diseases exhibited higher natural vegetation cover, greater primary and secondary vegetation loss, poorer socioeconomic conditions, and higher temperatures.

Spatiotemporal analysis identified critical transmission areas for the leishmaniasis in Brazil, aiding targeted surveillance and control.