Visceral Leishmaniasis and Disposal of Solid Waste in Minas Gerais, Brazil

Visceral leishmaniasis (VL) is a vector-borne disease that is caused by the protozoan Leishmania infantum and transmitted to humans and other mammals through the bites of infected female sandflies. VL has been prevalent in Minas Gerais, Brazil, since the 1940s. As the vector completes its reproductive cycle in the soil with organic matter, the association between the occurrence of VL and unimproved solid waste disposal sites has been investigated. Thus, in this study, we analyzed the relationship of waste disposal conditions, inadequacies in disposal, and waste collection with the rates of VL, using statistical regression models. A case-control study was conducted to elucidate the relationship between VL and waste management; sick individuals (cases) were compared to healthy individuals (control), to determine the cause, by constructing a multiple regression model to analyze data through a stepwise method. In Minas Gerais, according to the reports of the government in 2017, 60.1% of the urban population has access to an adequate final disposal system for urban solid waste, with an increase of 2.3% compared to the size of the disposal system in 2016. Thus, almost 40% of the population is forced to use poor or unimproved waste disposal sites. The results confirmed the direct relationship between VL and the unimproved disposal of solid waste in the municipalities (waste coverage collection: p = 0.004; waste found in the streets: p = 9.69 × 10–13). These rates also indicated that the proper management of wastes can help to combat VL by considerably reducing the breeding sites of sandflies, curbing adverse health effects, and improving the health of the population.