Carbapenemase IncF-borne blaNDM-5 gene in the E. coli ST167 high-risk clone from canine clinical infection, Italy

The blaNDM-5-producing E. coli Sequence Type (ST)167 high-risk clone is emerging worldwide in human clinical cases, while its presence in companion animals is sporadic and has never been described in Italy. Using a combined Oxford Nanopore (ONT) long-reads and Illumina short-reads sequencing approach, an E. coli ST167 isolated from a hospitalized dog, was in-depth characterized by WGS and the plasmid containing blaNDM-5 was fully reconstructed. The complete sequence of the pMOL008 mosaic plasmid (F36:F31:A4:B1; pMOL008) harbouring blaNDM-5, was resolved and characterized. Moreover, a (pro)phage and IncFII, containing blaCMY-2 and ermB, and IncI2 plasmid types were also identified. pMOL008 was almost identical to blaNDM-5-containing plasmids from E. coli ST167 isolated from Italian human clinical cases and from a Swiss dog and colonized humans. blaNDM-5 was located in a class 1 integron together with aadA2, aac(3)-IIa, mph(A), sul1, tet(A) and dfrA12. The risk of spill-over and spill-back transmission of carbapenem-resistance genes, related plasmids and strains between humans and dogs, represents a Public Health threat and highlights the importance of the One Health approach for the AMR surveillance.

Automated summary

The blaNDM-5-producing E. coli ST167 high-risk clone is emerging globally in human clinical cases, but has only been sporadically found in companion animals and has not been described in Italy. The sequence analysis revealed that the plasmid pMOL008 carrying blaNDM-5 is nearly identical to those found in human clinical cases in Italy and in colonized humans and a dog in Switzerland. The presence of carbapenem-resistance genes in the plasmid poses a public health threat and underscores the importance of the One Health approach for antimicrobial resistance surveillance.