Characterization of Salmonella enterica Serovar 4,[5],12:i:- Isolates from Korean Food Animals.

Salmonella enterica subspecies enterica serovar 4,[5],12:i:-, a monophasic variant of Salmonella Typhimurium, has emerged as one of the most common serotypes related to human salmonellosis. In this study, the 22 isolates of S. 4,[5],12:i:- from food animals were identified by a specific multiplex polymerase chain reaction between 2009 and 2012. The isolation rate of S. 4,[5],12:i:- accounted for 1.7% (22/1271) of Salmonella spp. isolates from food animal origins: more specifically, 7.6% (18/235) from pigs and 0.6% (4/686) from chickens. The predominant S. 4,[5],12:i:- isolates in Korea belonged to phage type DT193 (12/22) with ampicillin-streptomycin-sulfonamide-tetracycline (ASSuT) resistance pattern (9/22). The XbaI-pulsed-field gel electrophoresis (PFGE) analysis revealed 11 different pulsotypes, and the major X-1 pattern was shared by 8 isolates. The isolates belonging to pattern X-1 were further subdivided into three BlnI-PFGE patterns and four variable-number tandem-repeat analysis (MLVA) allele combinations. The combining of MLVA and PFGE data could be valuable in characterizing highly clonal strains and discriminating their epidemiological relationship.