Considerations on the epidemiology and transmission of Chagas disease in the Brazilian amazon

Epidemiology, control and surveillance of Chagas disease: 100 years after its discovery

“…Congenital transmission exhibits great regional variation, from 0.5-10% of cases in places like Chile, Bolivia and Paraguay. Although oral transmission is accidental, nowadays it can be considered endemic in the Amazon Region (Fraiha et al 1995, Valente et al 1999, Junqueira et al 2005, Pinto et al 2008.…”

“…Shaw et al (1969) described another four acute cases in Belém, the capital of PA, in Northern Brazil. Since then, more than 400 acute cases have been reported, most of them from outbreaks likely caused by oral transmission in the states of PA, Amapá and Amazonas (AM), Brazil (Valente & Valente 1993, Valente et al 1999, Pinto et al 2004, 2008, Coura 2006. Serological surveys and cross-sectional studies carried out by Fundação Nacional de Saúde from 1975-1980, in different states in the Brazilian Amazon Region, and by Coura et al from 1971Coura et al from -2002 in AM showed prevalences ranging from 2.4-13.2% (Camargo et al 1984, Coura et al 1999.…”

Morphobiological aspects of Rhodnius brethesi Matta, 1919 (Hemiptera:Reduviidae) from the Upper and Middle Negro River, Amazon region of Brazil: I - scanning electron microscopy

“…So far, it is unclear whether these growing numbers of human cases are due to increased transmission or whether they are the result from an active search for positive cases. This latter is the case in the state of Pará, where greater numbers of small outbreaks attributed to contamination by oral transmission have been described (Valente et al 1999).One of the epidemiological profiles discerned in the Amazon region that has received deserved attention is the one found in the Upper and Middle Negro River region, microregion of Negro River in the state of Amazonas. Initial investigations by Coura et al (1994Coura et al ( , 1995 indicated that the presence of human infection in areas of the Negro River were associated with extractive activities relating to the collection of fiber from the native palm tree Leopoldinia piassaba Wallace, 1853.…”

“…The buccula and the stridulatory sulcus presented notable differences in specimens of different genera and also of different species. These data make it possible to suggest that the details presented in these structures can be included as diagnostic characteristics to be used in new dichotomous keys, thereby contributing towards studies of taxonomy and systematics and furnishing backing for comparative analysis of specimens collected from different localities.Key words: Rhodnius brethesi -external morphology -taxonomy -scanning electron microscopy -Amazon region -Brazil Over recent years, attention has been drawn to Chagas disease infection in the Amazon region of Brazil because of increased numbers of reports of acute cases and the presence of individuals who are serologically positive for this infection (Coura et al 1995, 2002a, Fraiha Neto et al 1995, Valente et al 1999, Dias et al 2002. So far, it is unclear whether these growing numbers of human cases are due to increased transmission or whether they are the result from an active search for positive cases.…”

Survival of Trypanosoma cruzi in sugar cane used to prepare juice

“…There are several reports on the outbreak of human Chagas disease in Brazil, probably by oral contamination 8,9,11 . Only a few experimental studies have attempted to demonstrate the likelihood of this route of contamination 7,10 .…”