BackgroundTrypanosoma cruzi is classified into six discrete taxonomic units (DTUs). For this classification, different biological markers and classification criteria have been used. The objective was to identify the genetic profile of T. cruzi samples isolated from patients of two municipalities of Jequitinhonha Valley, MG, Brazil.MethodsMolecular characterization was performed using two different criteria for T. cruzi typing to characterize 63 T. cruzi samples isolated from chronic Chagas disease patients. The characterizations followed two distinct methodologies. Additionally, the RAPD technique was used to evaluate the existence of genetic intragroup variability.ResultsThe first methodology identified 89 % of the samples as TcII, but it was not possible to define the genetic identity of seven isolates. The results obtained with the second methodology corroborated the classification as TcII of the same samples and defined the classification of the other seven as TcVI. RAPD analysis showed lower intra-group variability in TcII.ConclusionsThe results confirmed the preliminary data obtained in other municipalities of the Jequitinhonha Valley, showing a predominance of TcII, similar to that verified in northeast/south axis of Brazil and the first detection of TcVI in the study region. The second protocol was more simple and reliable to identify samples of hybrid character.

The results indicate the presence of an association between the biological behavior in mice and the genetic characteristics of the parasites. The study also confirmed general data from Brazil where T. cruzi II lineage is the most prevalent in the domiciliary cycle and generally has low virulence, with some strains capable of inducing inflammatory processes and fibrosis.

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O rompimento da barragem de rejeitos de Fundão (Samarco S/A no município de Mariana – MG), em novembro de 2015, liberou 55 milhões m³ de rejeitos, provocando a morte da biota aquática na calha central do Rio Doce e danos nos ecossistemas adjacentes. No início de 2017, iniciou-se uma epidemia de febre amarela em Minas Gerais, com grande parte das ocorrências na região da bacia do Rio Doce. Assim, este trabalho buscou verificar a existência de relação entre os dois fatos ocorridos. Os dados epidemiológicos e de monitoramento da água foram relacionados por meio de Análise de Componentes Principais (ACP), não sendo identificada relação direta entre o dano ambiental e a epidemia. Todavia, fatores como a dizimação dos predadores do mosquito vetor, a proximidade entre o homem e as florestas, e a baixa cobertura vacinal da população foram também considerados como aspectos relevantes. Desse modo, esse estudo analisou os fatores que devem ser considerados em conjunto, no intuito de compreender o aumento da febre amarela na Bacia do Rio Doce após o rompimento da barragem de Fundão.