 The disease is present in 18 countries on the American continents , ranging from the southern United States to northern Argentina . Chagas exists in two different ecological zones . In the Southern Cone region , the main vector lives in and around human homes . In Central America and Mexico , the main vector species lives both inside dwellings and in uninhabited areas . In both zones , Chagas occurs almost exclusively in rural areas , where <unk> breed and feed on the more than 150 species from 24 families of domestic and wild mammals , as well as humans , that are the natural reservoirs of T. cruzi . 
