Low level of polymyxin resistance among nonclonal mcr-1-positive Escherichia coli from human sources in Brazil

Abstract

We report 26 human isolates of mcr-1-positive Escherichia coli, most of them (65.4%) with a polymyxin B MIC of 2 mg/L. Seventeen out of the 24 mcr-1-positive E. coli proved to be nonclonal by rep-PCR which strengthens the hypothesis of environmental or animal origin of these strains and reinforces the one health context of antimicrobial resistance.

Keywords: Antimicrobial resistance; E. coli; One health; Polymyxin resistance; mcr-1.