Cross-Sectional Serological Survey of Human Fascioliasis in Canutama Municipality in Western Amazon, Brazil.

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.

Serological survey for Chagas disease in the rural areas of Manaus, Coari, and Tefé in the Western Brazilian Amazon / Inquérito sorológico para doença de Chagas em áreas rurais de Manaus, Coari e Tefé na Amazônia Ocidental

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 percent) were natives of the State of Amazonas, 666 (52.7 percent) were male, and 948 (75.1 percent) 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 percent and 0.9 percent 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 percent. CONCLUSIONS: The results of this study ratify the importance of monitoring CD cases in Amazonia, particularly in the state of Amazonas.

INTRODUÇÃO: 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 por cento ) as quais eram autóctones do Estado do Amazonas, 666 (52,7 por cento) do sexo masculino, 948 (75,1 por cento) 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 por cento e de 0,9 por cento 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 por cento. CONCLUSÕES: O resultado deste estudo reforça a importância do monitoramento de casos da doença de Chagas na Amazônia, em especial no Amazonas.

Serological survey for Chagas disease in the rural areas of Manaus, Coari, and Tefé in the Western Brazilian Amazon.

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.