Characterization of plasmid-mediated quinolone resistance genes in Escherichia coli isolated from poultry and swine production chain

Abstract

The selective pressure caused by the antimicrobials used as growth promoters in animal production is a current concern worldwide. Recently, several studies have shown that strains of pathogenic and/or multidrug-resistant bacteria are selected in the context of animal production. Among the antibiotics that have showing increased levels of resistance are the quinolones and fluoroquinolones. Until 1998 the resistance to quinolones was assigned to only mechanisms mutation in DNA gyrase and topoisomerase IV in bacterial DNA. The emergence of resistance to quinolones mediated by plasmids and dissemination of these elements brought the issue of animals serve as a source of genes for resistance to this class. Several studies show that the consumption of animal foods, especially poultry and pork, and proximity to these animals as a fundamental element in the epidemiological chain of human infections by bacteria such Salmonella spp, Campylobacter spp., and more recently by Escherichia coli. Taking into account the importance of the issue for public health, the importance of poultry and pigs in the Brazilian economy and the dearth of research on this topic in Brazil, this project is to evaluate the molecular epidemiology and phenotypically and genotypically characterize the resistance plasmids quinolones present in Escherichia coli isolated from different stages of swine and poultry production in Brazil. (AU)