Trypanosoma Cruzi Strains From Triatomine Collected In Bahia And Rio Grande Do Sul, Brazil.

Collection of triatomines in domestic, peridomestic and sylvatic environments in states of Bahia and Rio Grande do Sul, Northeastern and Southern Brazil respectively, and isolation of Trypanosoma cruzi strains. First, the captured triatomines were identified using insect identification keys, then their intestinal content was examined by abdominal compression, and the samples containing trypanosomatid forms were inoculated in LIT medium and Swiss mice. Six triatomine species were collected in cities in Bahia, namely Panstrongylus geniculatus (01), Triatoma melanocephala (11), T. lenti (94), T. pseudomaculata (02), T. sherlocki (26) and T. sordida (460), and two in cities in Rio Grande do Sul, namely T. circummaculata (11) and T. rubrovaria (115). Out of the specimens examined, T. cruzi was isolated from 28 triatomine divided into four different species: T. melanocephala (one), T. lenti (one), T. rubrovaria (16) and T. sordida (10). Their index of natural infection by T. cruzi was 6.4%. The isolation of T. cruzi strains from triatomines found in domestic and peridomestic areas shows the potential risk of transmission of Chagas disease in the studied cities. The maintenance of those T. cruzi strains in laboratory is intended to promote studies that facilitate the understanding of the parasite-vector-host relationship.

Clustering Of Water Bodies In Unpolluted And Polluted Environments Based On Escherichia Coli Phylogroup Abundance Using A Simple Interaction Database.

Different types of water bodies, including lakes, streams, and coastal marine waters, are often susceptible to fecal contamination from a range of point and nonpoint sources, and have been evaluated using fecal indicator microorganisms. The most commonly used fecal indicator is Escherichia coli, but traditional cultivation methods do not allow discrimination of the source of pollution. The use of triplex PCR offers an approach that is fast and inexpensive, and here enabled the identification of phylogroups. The phylogenetic distribution of E. coli subgroups isolated from water samples revealed higher frequencies of subgroups A1 and B23 in rivers impacted by human pollution sources, while subgroups D1 and D2 were associated with pristine sites, and subgroup B1 with domesticated animal sources, suggesting their use as a first screening for pollution source identification. A simple classification is also proposed based on phylogenetic subgroup distribution using the w-clique metric, enabling differentiation of polluted and unpolluted sites.