ABSTRACT
BACKGROUND Monitoring and analysing the infection rates of the vector of Trypanosoma cruzi, that causes Chagas disease, helps assess the risk of transmission. OBJECTIVES A study was carried out on triatomine in the State of Paraná, Brazil, between 2012 and 2021 and a comparison was made with a previous study. This was done to assess the risk of disease transmission. METHODS Ecological niche models based on climate and landscape variables were developed to predict habitat suitability for the vectors as a proxy for risk of occurrence. FINDINGS A total of 1,750 specimens of triatomines were recorded, of which six species were identified. The overall infection rate was 22.7%. The areas with the highest risk transmission of T. cruzi are consistent with previous predictions in municipalities. New data shows that climate models are more accurate than landscape models. This is likely because climate suitability was higher in the previous period. MAIN CONCLUSION Regardless of uneven sampling and potential biases, risk remains high due to the wide presence of infected vectors and high environmental suitability for vector species throughout the state and, therefore, improvements in public policies aimed at wide dissemination of knowledge about the disease are recommended to ensure the State remains free of Chagas disease.
ABSTRACT
O objetivo do estudo foi avaliar o desempenho da reação em cadeia da polimerase (PCR) para detectar o DNA de Trypanosoma cruzi no sangue de camundongos infectados com clones do protozoário pertencentes aos genótipos 19, 20 (T. cruzi I), 39 e 32 (T. cruzi II), comparando-o com o exame de sangue a fresco (ESF), a hemocultura (HC) e o teste imunoenzimático (ELISA). Foram analisadasamostras de sangue de camundongos BALB/c experimentalmente infectados com 20 clones. A positividade da PCR foi significativamente superior à das demais técnicas estudadas e a seguinte ordem de positividade foi observada: PCR (100,00) > ELISA(94,44) > HC (78,86) > ESF (73,28). Ao contrário da ELISA, HC e ESF, a positividade da PCR não variou de acordo com o genótipo. Esses dados mostram o potencial da técnica da PCR para o diagnóstico da doença de Chagas.
Subject(s)
Animals , Mice , Blood Chemical Analysis , Chagas Disease/diagnosis , Enzyme-Linked Immunosorbent Assay , Immunoenzyme Techniques , Mice , Polymerase Chain Reaction , Trypanosoma cruzi , TrypanosomiasisABSTRACT
Os autores documentan a cardiopatia difusa fibrosante, com todos os sintomas clínicos e dados de autópsia pertinente a insuficiência cardíaca congestiva, em um dos 21 cäes infectados com a cepa Colombiana (cinco morreram na fase aguda e quatro continuam vivos) e cinco, dos 13 infectados com a cepa Berenice-78 (oito morrerm na fase aguda), num período de oito anos de observaçäo. Em vista destes resultados, os autores sugerem que o cäo possa vir a ser um modelo experimental, adequado par o estudo da história da doença de Chagas, preenchendo os requisitos estabelecidos pelo Comitê Assessor de Doença de Chagas do Programa Especial de Pesquisa e Treinamento em Doenças Tropicais da Organizaçäo Mundial de Saúde