Emergence of bla(OXA-1)- and mph(A)-Producing Vibrio furnissii Isolated from Hospital Sewage

Cephalosporins and azithromycin are clinical antibiotics used to treat infections. Co-resistance to cephalosporins and azithromycin has been observed in some Enterobacterales, but it has only rarely been reported in Vibrio species. In this study, we isolated a cephalosporin- and azithromycin-resistant V. furnissii strain, VFN3, from hospital sewage. Whole-genome sequencing results showed that the strain VFN3 possesses an IncA/C2 plasmid, pVFN3-blaOXA-193K. This conjugative plasmid carries several clinically relevant drug resistance genes, including mph(A) and bla(OXA-1). We also found that in the strain VFN3, mph(A) and bla(OXA-1) are surrounded by insertion sequences and class I integrons, respectively. These data suggest that mobile elements mediate the transfer of mph(A) and bla(OXA-1). This is the first reported Vibrio species that possesses an mph(A)- and bla(OXA-1)-bearing conjugative plasmid. The emergence of this conjugative multi-drug-resistance plasmid is of great concern to public health.