Phylogenetically Diverse Escherichia coli Strains from Chicken Coharbor Multiple Carbapenemase-Encoding Genes (bla NDM -bla OXA-blaIMP)

Carbapenem-resistant Enterobacteriaceae (CRE) has been a public health risk in several countries, and recent reports indicate the emergence of CRE in food animals. This study was conducted to investigate the occurrence, resistance patterns, and phylogenetic diversity of carbapenem-resistant E. coli (CREC) from chicken. Routine bacteriology, PCR detection of E. coli species, multiplex PCR to detect carbapenemase-encoding genes, and phylogeny of CRE E. coli were conducted. The results show that 24.36% (19/78) were identified as CREC based on the phenotypic identifications of which 17 were positive for the tested carbapenemases genes. The majority, 57.99% (11/19), of the isolates harbored multiple carbapenemase genes. Four isolates harbored all bla NDM, bla OXA, and bla IMP, and five and two different isolates harbored bla NDM and bla OXA and bla OXA and bla IMP, respectively. The meropenem, imipenem, and ertapenem MIC values for the isolates ranged from 2 μg/mL to ≥256 μg/mL. Phylogenetic grouping showed that the CREC isolates belonged to five different groups: groups A, B1, C, D, and unknown. The detection of CREC in this study shows that it has become an emerging problem in farm animals, particularly, in poultry farms. This also implies the potential public health risks posed by CRE from chicken to the consumers.