e Here, we report a case of OXA-48-producing Salmonella enterica serovar Kentucky of sequence type 198 (ST198) from perianal screening cultures of a patient transferred from Libya to Switzerland. The bla OXA-48 gene was carried by Tn1999.2 and located on an ϳ60-kb IncL/M plasmid. This Salmonella strain also possessed the bla VEB-8 , aac(6)-Ib, tet(A), sul1, and mphA resistance genes and substitutions in GyrA (Ser83Phe and Asp87Asn) and ParC (Ser80Ile). This finding emphasizes that prompt screening strategies are essential to prevent the dissemination of carbapenemase producers imported from countries where they are endemic.

The spread of plasmid-mediated carbapenemases within Klebsiella oxytoca is well-documented. In contrast, data concerning the closely-related species Klebsiella grimontii are scarce. In fact, despite the recent report of the first bla KPC-2 -producing K. grimontii , nothing is known about its clonality and antibiotic resistance patterns. In a retrospective search in our collection, we identified 2 bla VIM -positive K. oxytoca strains. Whole-genome sequencing with both Illumina and Nanopore indicated that our strains actually belonged to K. grimontii and were of sequence type (ST) 172 and ST189. Moreover, the two strains were associated with 297kb IncHI2/HI2A-pST1 and 90.6kb IncFII(Yp) plasmids carrying bla VIM-1 together with mcr-9 and bla VIM-1 , respectively. In the IncHI2/HI2A plasmid, bla VIM-1 was located in a class 1 integron (In 110 ), while mcr-9 was associated to the qseC - qseB- like regulatory elements. Overall, this plasmid showed to be very similar to those carried by other Enterobacterales isolated from food and animal sources (e.g., Salmonella and Enterobacter spp. detected in Germany and Egypt). The IncFII(Yp) plasmid was unique and its bla VIM-1 region was associated to a rare integron (In 1373 ). Mapping of In 1373 indicated a possible origin in Austria from an Enterobacter hormaechei carrying a highly similar plasmid. Core-genome phylogenies indicated that the ST172 K. grimontii belonged to a clone of identical Swedish and Swiss strains (≤15 SNVs to each other), whereas the ST189 strain was sporadic. Surveillance of carbapenemase-producing K. oxytoca strains should be reinforced to detect and prevent the dissemination of new species belonging to the Klebsiella genus.

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