Colistin and β-lactam resistance in Escherichia coli isolates from bovines, swine, and humans.

Introduction: Colistin and β-lactams are widely investigated because of their effectiveness in the treatment of human diseases. This study investigated the phenotypic and genotypic profiles of colistin- and β-lactam-resistant Escherichia coli (n = 235) obtained from bovines, swine, and workers from a mixed slaughterhouse in Brazil.

Methodology: The disk diffusion method was used to test the resistance against β-lactams (amoxicillin, ampicillin, cefaclor, cefazolin, cefepime, cefotaxime, ceftazidime, ceftriaxone, imipenem, meropenem, and aztreonam).