title: An ecological overview on the factors that drives to Trypanosoma cruzi oral transmission.
abstract: American trypanosomiasis is one of the few native parasites of this continent. As a zoonosis, Trypanosoma cruzi infects about 180 species out of 25 families of mammals. Its regular transmission is through triatomines, which can easily transmit parasites either by the skin route (contamination of mammals skin with their feces) or by oral route (ingestion of food contaminated with complete triatomines or their feces) and additionally through haematogenous via (congenital and transfusional) and by tissues (transplants). The oral route, which seems to be the ancestral form of transmission to wild and domestic mammals, has recently become more important after the success achieved in the control of domicile vectors using residual pesticides. From its initial diagnosis in 1967, tens of oral outbreaks have been diagnosed mostly in the Brazilian Amazon and subsequently in other four countries in South America. Environmental imbalance caused by man through the invasion and deforestation of woodlands, results in reduction of biodiversity of mammals as food source for triatomines, affecting the "dilution effect" of T. cruzi in the nature increasing the risk of human infection. On the other hand, triatomines invade houses looking for new blood sources. One of the consequences of domiciliated triatomines is the food contamination spread, especially in home-made juices, which has been the source of infection of most oral outbreaks. Other biotic and abiotic factors help to explain the recent increase of oral transmission outbreaks of Chagas disease, distributed in nine eco-regions of America.
authors.affiliation: Sección de Inmunología, Instituto de Medicina Tropical, Facultad de Medicina, Universidad Central de Venezuela, Venezuela; Cátedra de Parasitología, Escuela de Medicina "Luis Razetti", Facultad de Medicina, Universidad Central de Venezuela, Venezuela. Electronic address: belkisuole@gmail.com.
authors.forename: Belkisyolé Alarcón
authors.initials: BA
authors.lastname: de Noya
authors.affiliation: Cátedra de Parasitología, Escuela de Medicina "Luis Razetti", Facultad de Medicina, Universidad Central de Venezuela, Venezuela; Sección de Biohelmintiasis, Instituto de Medicina Tropical, Facultad de Medicina, Universidad Central de Venezuela, Venezuela; Centro para Estudios sobre Malaria, Instituto de Altos Estudios "Dr. Arnoldo Gabaldón", MPPS - Instituto Nacional de Higiene "Rafael Rangel", MPPS, Venezuela.
authors.forename: Oscar Noya
authors.initials: ON
authors.lastname: González
mesh_terms: D000818:Animals; D000829:Animals, Domestic / Q000469:parasitology; D000835:Animals, Wild / Q000469:parasitology; D014355:Chagas Disease / Q000453:epidemiology / Q000469:parasitology / Q000635:transmission*; D004196:Disease Outbreaks; D004463:Ecology; D005243:Feces / Q000469:parasitology; D005260:Female; D005506:Food Contamination; D000067030:Fruit and Vegetable Juices / Q000469:parasitology*; D006801:Humans; D008297:Male; D013020:South America / Q000453:epidemiology; D014224:Triatoma / Q000469:parasitology*; D014349:Trypanosoma cruzi / Q000469:parasitology*; D015047:Zoonoses / Q000469:parasitology*
keywords: Chagas disease; Eco-regions; Ecology; Epidemiology; Oral transmission