LAUSR

OBJECTIVE Salmonella enterica subsp. enterica serovar Kentucky has been associated with the worldwide Ciprofloxacin-resistant (CIPR) S. Kentucky Sequence type 198 (ST198) epidemic clone, mostly recovered from poultry farms and products. The aim of this study was to examine whether this expanding clone exists in the Lebanese broiler chain. METHODS A number of eight CIPR and Extended spectrum cephalosporin (ESCs) resistant S. Kentucky previously isolated from Lebanese broilers were genetically characterized by WGS. RESULTS Seven out of eight isolates have been shown to belong to the ST198 and were phylogenetically closely related. They all harbored mutations in chromosomal-quinolone resistance genes gyrA and parC with double and single substitutions, respectively. blaTEM-1B and blaCMY-2 genes were both detected in six isolates. The insertion sequence ISEcp1 was localized upstream of blaCMY-2, harbored by IncI1 plasmids in four strains. An IS10 transposition coupled to homologous recombination (HR) at transposition sites mediated CMY-2 plasmid integration into the chromosome of one strain. The Aminoglycosides (aadA7 and aac (3)-Id), tetracyclines (tet (A)) and sulfonamides (sul1) resistance genes were detected in five strains among which four were positive for the presence of Salmonella Genomic Island 1 (SGI1) variant SGI1-K. All studied isolates harbored a variety of Salmonella Pathogenicity Islands (SPIs) as well as common regulatory and virulence genes. CONCLUSION Here we report for the first time in Lebanon, a case of detection and dissemination of the emerging highly drug-resistant S. Kentucky ST198. Our findings shed new light on this clone as a potential public health threat.