Chagas disease: control, elimination and eradication. Is it possible?

Abstract

From an epidemiological point of view, Chagas disease and its reservoirs and vectors can present the following characteristics: (i) enzooty, maintained by wild animals and vectors, with broad occurrence from southern United States of America (USA) to southern Argentina and Chile (42ºN 49ºS), (ii) anthropozoonosis, when man invades the wild ecotope and becomes infected with Trypanosoma cruzi from wild animals or vectors or when the vectors and wild animals, especially marsupials, invade the human domicile and infect man, (iii) zoonosis-amphixenosis and exchanged infection between animals and humans by domestic vectors in endemic areas and (iv) zooanthroponosis, infection that is transmitted from man to animals, by means of domestic vectors, which is the rarest situation in areas endemic for Chagas disease. The characteristics of Chagas disease as an enzooty of wild animals and as an anthropozoonosis are seen most frequently in the Brazilian Amazon and in the Pan-Amazon region as a whole, where there are 33 species of six genera of wild animals: Marsupialia, Chiroptera, Rodentia, Edentata (Xenarthra), Carnivora and Primata and 27 species of triatomines, most of which infected with T. cruzi . These conditions place the resident populations of this area or its visitors - tourists, hunters, fishermen and especially the people whose livelihood involves plant extraction - at risk of being affected by Chagas disease. On the other hand, there has been an exponential increase in the acute cases of Chagas disease in that region through oral transmission of T. cruzi , causing outbreaks of the disease. In four seroepidemiological surveys that were carried out in areas of the microregion of the Negro River, state of Amazonas, in 1991, 1993, 1997 and 2010, we found large numbers of people who were serologically positive for T. cruzi infection. The majority of them and/or their relatives worked in piassava extraction and had come into contact with and were stung by wild triatomines in that area. Finally, a characteristic that is greatly in evidence currently is the migration of people with Chagas disease from endemic areas of Latin America to non-endemic countries. This has created a new dilemma for these countries: the risk of transmission through blood transfusion and the onus of controlling donors and treating migrants with the disease. As an enzooty of wild animals and vectors, and as an anthropozoonosis, Chagas disease cannot be eradicated, but it must be controlled by transmission elimination to man.

Nitro/Nitrosyl-Ruthenium Complexes Are Potent and Selective Anti-Trypanosoma cruzi Agents Causing Autophagy and Necrotic Parasite Death

“…The main drugs used against this disease are benznidazole and nifurtimox (2), both of which are effective in curing the disease when administered during the acute phase but are less effective in patients that have progressed to the chronic phase (3). Furthermore, these drugs are not considered ideal, due to severe side effects, and drug resistance to T. cruzi strains has been reported (4).…”

Diagnosing Neglected Tropical Diseases in HIV Coinfection

“…The disease is caused by a protozoan called T. cruzi and it is transmitted mainly by the vectors' bite (triatomine insects). 47 However, transmission by blood transfusion can occur, mainly in nonendemic areas. 47 T. cruzi displays a relevant genetic variability shown by at least six discrete typing units (DTUs), from TcI to TcVI.…”

“…47 However, transmission by blood transfusion can occur, mainly in nonendemic areas. 47 T. cruzi displays a relevant genetic variability shown by at least six discrete typing units (DTUs), from TcI to TcVI. 48 Studies showing the impact of this genetic variability on HIV coinfection are scarce.…”

Prevalencia de anticuerpos contra Trypanosoma cruzi en mujeres embarazadas de zonas endémicas del departamento de Boyacá, Colombia

“…La estrategia para el control de esta enfermedad llamada "Iniciativa del Cono Sur", puesta en marcha en 1991, fue adoptada por Brasil, Uruguay, Paraguay, Argentina y Chile, y tuvo gran impacto en la reducción de los casos agudos y las nuevas infecciones por transmisión vectorial al hacer intervenciones con insecticida (5,6). La Organización Panamericana de la Salud (OPS) calculó que en 2006 la prevalencia de la enfermedad de Chagas en Colombia era de 436 000 casos y que 107 800 mujeres en edad fértil con edades entre 15 y 44 años padecían la enfermedad (7).…”