Prevalence of Colistin Resistance Gene <i>mcr-1</i> and Absence of <i>mcr-2</i> in Escherichia coli Isolated from Healthy Food-Producing Animals in Japan

Abstract

We screened mcr-1 and mcr-2 genes in 9,306 Escherichia coli strains isolated from healthy animals in the Japanese Veterinary Antimicrobial Resistance Monitoring (JVARM) system. mcr-1 was detected in 39 strains (5, 20, and 14 strains isolated from cattle, swine, and broilers, respectively), whereas mcr-2 was not detected. mcr-2 was also not detected with the investigation sequence homology search against our curated GenEpid-J database.