An ecological overview on the factors that drives to Trypanosoma cruzi oral transmission

• Published in: Acta tropica Vol. 151; pp. 94 - 102
• Main Authors: de Noya, Belkisyolé Alarcón, González, Oscar Noya
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.11.2015
• Subjects: Animals; Animals, Domestic - parasitology; Animals, Wild - parasitology; Chagas disease; Chagas Disease - epidemiology; Chagas Disease - parasitology; Chagas Disease - transmission; Disease Outbreaks; Eco-regions; Ecology; Epidemiology; Feces - parasitology; Female; Food Contamination; Fruit and Vegetable Juices - parasitology; Humans; Male; Oral transmission; South America - epidemiology; Triatoma - parasitology; Trypanosoma cruzi - parasitology; Zoonoses - parasitology; South America; Chagas disease; Ecology; Oral transmission; Eco-regions; Epidemiology
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/j.actatropica.2015.06.004

[Display omitted] •Deforestation reduce wildlife concentrating T. cruzi in few hosts.•Wildlife reduction promotes triatomines domiciliation looking for new blood sources.•Rapid defecation vectors infect through skin while any infected can contaminate food.•Survival of parasites in artisan fruit juices is key for T. cruzi oral transmission.•Most outbreaks occurred in Amazon, Andean and coastal eco-regions of South America. 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.