Spatiotemporal analysis of environmental factors associated with visceral leishmaniasis in northeastern Brazil, 2007–2022

Visceral leishmaniasis (VL), caused by the protozoan Leishmania infantum and transmitted by infected female sand flies, remains a significant public health concern in Brazil. This study investigates the clinical and epidemiological profile of VL, including its spatial distribution, temporal trends, and relationship with environmental factors - specifically sanitation, waste collection, and deforestation - in the northeastern region of Brazil from 2007 to 2022. Utilizing data from SINAN, IBGE, and MapBiomas, we observed a higher incidence of VL among males, children under ten years old, and indigenous populations, particularly in the states of Maranhão, Piauí, Bahia, and Ceará. Although a notable decreasing trend in VL cases was observed, the disease remains endemic in these areas. This research identified a positive correlation between VL incidence and environmental factors, such as inadequate sewage systems, insufficient waste collection, and deforestation. These findings suggest that improving urban infrastructure, adopting sustainable land-use practices, and enhancing epidemiological surveillance could help reduce VL incidence in northeastern Brazil.