Epidemiology of American tegumentary leishmaniasis in Bahia, Brazil (2007–2023)

Abstract

American tegumentary leishmaniasis (ATL) is a neglected zoonotic disease, endemic in Brazil, with variable clinical forms. In Bahia, ATL significantly impacts public health, requiring epidemiological surveillance and effective control measures. This study is intended to provide a detailed epidemiological and spatial analysis of ATL in the state of Bahia, Brazil, between 2007 and 2023. A retrospective approach was used to analyze ATL cases in Bahia through Notifiable Diseases Information System and Brazilian Institute of Geography and Statistics data. Methods included Bayesian smoothing, spatial autocorrelation analysis (Moran’s index), and thematic mapping with QGIS, complemented by statistical analysis using chi-squared tests and graphic tools in RStudio and SAS. Between 2007 and 2023, Bahia recorded approximately 44,427 ATL cases, with an average annual incidence rate of 17.62 cases per 100,000 inhabitants. The highest incidences rate occurred between 2010 and 2012, predominantly affecting males (59.98%) and individuals aged 15 to 34. The cutaneous form predominated (96.34%), in socially vulnerable populations, particularly those with low education. Spatial analysis identified critical clusters in municipalities, particularly during 2015–2023, with significant positive autocorrelation. Although ATL incidence rate in Bahia has declined, geographic expansion and critical clusters persist, requiring targeted surveillance. Incomplete records and treatment abandonment highlight gaps that require professional training and improved public health strategies. Integrated actions addressing socio-economic and environmental factors remain essential for effective disease control and management.