Emerging Chagas disease in Amazonian Brazil

A new survey of the serology of human Trypanosoma cruziinfection in the Rio Negro microregion, Brazilian Amazon: a critical analysis

“…The numbers of blood samples collected on filter paper, along with the percentage of positivity for T. cruzi infection, varied according to the number of people living in the area and their degree of exposure to infection in rural areas, especially in relation to piassava harvesters and their families. This characteristic has already been presented in previous studies by our group ( Coura et al 1995a , b , 2002a , b , 1999 , Albajar et al 2003 a, b, Junqueira et al 2005 , Xavier et al 2006 , Brum-Soares et al 2010 , Coura & Junqueira 2012 , Junqueira et al 2013 ).…”

“…Previously, between 1991-1997, we conducted three serological surveys of human Trypanosoma cruzi infection in the main settlement of the municipality of Barcelos, in the Rio Negro microregion, state of Amazonas (AM) ( Coura et al 1995a , b , 1999 , 2002a , b ). In the first serological survey (1991), in which 710 indirect immunofluorescence (IIF) tests were performed on blood collected on filter paper, 89 (12.5%) were positive.…”

“…As a result of this previous study and due to our greater experience with Chagas disease in the area ( Coura et al 2002b , Albajar et al 2003 , Junqueira et al 2005 , Xavier et al 2006 , Brum-Soares et al 2010 ), we decided in 2010 to conduct a new and larger serological survey in this area to correct certain technical interpretations regarding the previous serological surveys, including those related to immunofluorescence. For unknown reasons, intense immunofluorescence is frequently observed on the parasite's body in this region or at some points of its membrane, sometimes interpreted erroneously as positive when this staining is actually a false-positive.…”

The molecular epidemiology and phylogeography of Trypanosoma cruzi and parallel research on Leishmania: looking back and to the future

“…The sporadic cases of Chagas disease that do occur in the Amazon region are thus not due to domestic triatomine colonies but are caused by adult bugs attracted to dwellings, especially to artificial light. More than half of these cases are attributable to triatomine contamination of food and oral outbreaks, especially due to infected bugs entering juice presses, such as those used for açai palm or sugar cane (Coura et al 2002 ;Valente et al 2009 ;Pan American Health Organisation, 2009). Of triatomine species in the Brazilian Amazon, only Panstrongylus geniculatus has shown some new peridomestic adaptation to pig sties (Valente et al 1998 ;Feliciangeli et al 2004).…”

Enfermedades parasitarias de la cuenca Amazónica

“…Como conclusión, podemos considerar que la enfermedad de Chagas en la región amazónica presenta tres perfiles: 1) infección enzoótica entre animales y vectores silvestres en toda la región; 2 antropozoonosis cuando el hombre invade el ecótopo silvestre y se infecta o cuando vectores y animales silvestres invaden el domicilio humano e infectan directamente al hombre o contaminan sus alimentos con heces y orina, y 3 enfermedad endémica profesional de poblaciones que hacen explotación vegetal, principalmente recolectoras de palma de chiquichiqui en áreas específicas (Coura, et al, 1999(Coura, et al, , 2002 Los estudios de campo realizados en las comunidades indígenas tikunas y cocamas de la cuenca del Amazonas en Colombia, permitieron detectar la alta prevalencia de enfermedades como mansonelosis, leishmaniasis y malaria, y otras infecciones por protozoos y helmintos intestinales.…”