Risk is present in all rural areas. The highest incidence rates are reported from the states of Chiapas, Distrito Federal, Hidalgo, Guerrero, Jalisco, Morelos, Nayarit, Oaxaca, Puebla, Querétaro, Veracruz, Yucatán, and Zacatecas. Only sporadic cases are reported from the two northern states of Chihuahua and Coahuila. The blood supply is not screened appropriately.
Main vectors: Triatoma dimidiata is present in all affected areas; Rhodnius prolixus is present also in Oaxaca and Chiapas.