BackgroundChagas disease in the Amazon region is considered an emerging anthropozoonosis with a predominance of the discrete typing units (DTUs) TcI and TcIV. These DTUs are responsible for cases of acute disease associated with oral transmission. Chronic disease cases have been detected through serological surveys. However, the mode of transmission could not be determined, or any association of chronic disease with a specific T. cruzi DTU’s. The aim of this study was to characterize Trypanosoma cruzi in patients with chronic Chagas disease in the State of Amazonas, Brazil.MethodsBlood culture and xenodiagnosis were performed in 36 patients with positive serology for Chagas disease who participated in a serological survey performed in urban and rural areas of Manaus, Amazonas. DNA samples were extracted from the feces of triatomines used for xenodiagnosis, and the nontranscribed spacer of the mini-exon gene and the mitochondrial gene cytochrome oxidase subunit II (COII) were amplified by PCR and sequenced.ResultsBlood culture and xenodiagnosis were negative in 100% of samples; however, molecular techniques revealed that in 13 out of 36 (36%) fecal samples from xenodiagnosis, T. cruzi was characterized as the DTU TcI, and different haplotypes were identified within the same DTU.ConclusionThe DTU TcI, which is mainly associated with acute cases of Chagas disease in the Amazon region, is also responsible for chronic infection in patients from a region in the State of Amazonas.

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Introduction: Deforestation, uncontrolled forest, human population migration from endemic areas, and the large number of reservoirs and wild vectors naturally infected by Trypanosoma cruzi promote the endemicity of Chagas disease in the Amazon region. Methods: We conducted an initial serological survey (ELISA) in a sample of 1,263 persons; 1,095 (86.7%) were natives of the State of Amazonas, 666 (52.7%) were male, and 948 (75.1%) were over 20 years old. Serum samples that were found to be reactive, indeterminate, or inconclusive by indirect immunofluorescence (IFI) or positive with low titer by IFA were tested by Western blot (WB). Serologically confirmed patients (WB) were evaluated in terms of epidemiological, clinical, ECG, and echocardiography characteristics. Results: Fifteen patients had serologically confirmed T. cruzi infection, and 12 of them were autochthonous to the state of Amazonas, for an overall seroprevalence of 1.2% and 0.9% for the state of Amazonas. Five of the 15 cases were males, and the average age was 47 years old; most were farmers with low education. One patient who was not autochthonous, having originated from Alagoas, showed right bundle branch block, bundle branch block, and anterosuperior left ventricular systolic dysfunction with an ejection fraction of 54%. Conclusions: The results of this study ratify the importance of monitoring CD cases in Amazonia, particularly in the state of Amazonas. Keywords: Chagas Disease. Serological Survey. Brazilian Amazon. RESUMOIntrodução: Na Amazônia, o desmatamento desordenado da floresta, as migrações populacionais humanas de áreas endêmicas e o grande número de reservatórios e vetores silvestres naturalmente infectados por Trypanosoma cruzi, favorece a endemicidade da doença de Chagas nessa região. Métodos: Foi realizado um inquérito sorológico inicial por ensaio imunoenzimático (ELISA), em uma amostra de 1.263 pessoas, 1.095 (86,7% ) as quais eram autóctones do Estado do Amazonas, 666 (52,7%) do sexo masculino, 948 (75,1%) com idade superior a 20 anos. As amostras de soro reativas, indeterminadas ou inconclusivas por imunofluorescência indireta (IFI) positivas ou com baixo título na IFI foram submetidas ao Western blot (WB). Os pacientes com sorologia confirmada (WB) foram avaliados do ponto de vista epidemiológico, clínico, eletro e ecocardiográfico. Resultados: Quinze pacientes tiveram sorologia confirmada para infecção por T. cruzi, 12 dos quais autóctones do Estado do Amazonas, com uma prevalência sorológica geral de 1,2% e de 0,9% para o Estado do Amazonas. Entre os 15 casos com sorologia positiva, cinco eram do sexo masculino, média de idade de 47 anos, baixa escolaridade e a maioria agricultores. Um paciente não autoctone, procedente de Alagoas, apresentou bloqueio de ramo direito, bloqueio divisional ântero-superior e disfunção sistólica ventricular esquerda com fração de ejeção de 54%. Conclusões:O resultado deste estudo reforça a importância do monitoramento de casos da doença de Chagas na Amazônia, em especial no Amazonas. Pa...

Background Fascioliasis is an important parasitic disease. In the northern region of Brazil, a human parasite infection has been reported through a coprological survey. Eggs of Fasciola hepatica were found in fecal samples of 11 individuals. Knowledge of the infection in animals or the presence of snails is necessary to address the possibility of the parasite cycle occurrence in that region. The aim of this study was to describe the transmission of human fascioliasis in Canutama, Amazonas, in Western Amazonia, Brazil. Methods Serological (ELISA and Western Blot, WB) and parasitological analyses were carried out in humans. In addition, the presence of the intermediate snail host within the community was examined. Results A total of 434 human samples were included in the study, of which 36 (8.3%) were reactive by ELISA and 8 (1.8%) were reactive by WB. Fasciola hepatica eggs were found in one human sample. The occurrence of the intermediated host was recorded and 31/43 specimens were identified as Lymnaea columella. Conclusion. Canutama constitutes a focus of transmission of human fascioliasis. This study describes the first serological survey for human fascioliasis, as well as its simultaneous occurrence in human hosts and possible intermediates performed in northern Brazil.

This study aims to analyze factors related to the occurrence of American Tegumentary Leishmaniasis in the Purus Region, based on the reporting of cases between 2001 and 2013, correlating them with livelihoods and subsistence farming in the region, and analyzing them in regards to sex, age, clinical form, occupation, diagnostic methods and seasonality. The analysis parameter which was used included all cases of American Tegumentary Leishmaniasis in each sub-region by municipality. The Purus Region, between the states of Amazonas and Acre, consists of three sub-regions: Upper, Middle, and Lower Purus. We observed that socio-environmental impacts influenced the livelihoods of the human population and that the interaction with extractive activities, especially latex and Brazil nut collecting, where the labor regime implies a long stay in the jungle, leads to socio-environmental conditions that are favorable to the contraction of American Tegumentary Leishmaniasis. During the referred period, there were 13,971 cases of American Tegumentary Leishmaniasis distributed among the sub-regions: High (12611 cases = 90.27%), Middle (1225 cases = 8.77%) and Lower (135 cases = 0.96%). Among the 22 municipalities that were studied, Rio Branco stands out with 31.6% of cases, followed by Xapuri with 12.6% and Sena Madureira with 12.5%. In the results, we highlight the high percentage (20.8%) of mucous forms; the age group from 11 to 50 (70.2%), however, 20.2% were in the age group of 1 month to 10 years of age; cases in males were 69.8%, and, in the reports examined, 43.7%. cited their occupation as extractivism. A statistically significant negative association was demonstrated between cutaneous leishmaniasis and rainfall between Purus municipalities. However, in regards to the association of cutaneous leishmaniasis for both, temperature and Municipal Human Development Index—MHDI, no significant associations were found in Purus. We concluded that American Tegumentary Leishmaniasis occurring in the Purus Region is related to two distinct aspects: the development of enterprises that extend the agricultural frontier, and a change in lifestyle, namely the extraction of wood as an occupation, which has, as a consequence, an environmental impact and creates difficulties in accessing treatment.