title: Molecular characterization showed limited genetic diversity among Salmonella Enteritidis isolated from humans and animals in Malaysia.
abstract: Salmonella enterica serovar Enteritidis (S. Enteritidis) is the most common causative agent of non-typhoidal salmonellosis in Malaysia. We aimed to characterize S. Enteritidis isolated from humans and animals by analyzing their antimicrobial resistance profiles and genotypes. A total of 111 strains were characterized using multiple-locus variable-number tandem repeat analysis, pulsed-field gel electrophoresis, and antimicrobial susceptibility testing. Both typing methods revealed that genetically similar S. Enteritidis strains had persisted among human and animal populations within the period of study (2003-2008). Only 39% of the strains were multi-drug resistant (i.e., resistant to 3 or more classes of antimicrobial agents), with a majority (73%) of these in low-risk phase (multiple antibiotic resistant index <0.20). Limited genetic diversity among clinical and zoonotic S. Enteritidis suggested that animals are possible sources of human salmonellosis. The degree of multi-drug resistance among the strains was generally low during the study period.
authors.affiliation: Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia; Laboratory of Biomedical Science and Molecular Microbiology, Institute of Graduate Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Soo Tein
authors.initials: ST
authors.lastname: Ngoi
authors.forename: Kwai Lin
authors.initials: KL
authors.lastname: Thong
mesh_terms: D000818:Animals; D004269:DNA, Bacterial; D024881:Drug Resistance, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D014644:Genetic Variation; D006801:Humans; D008296:Malaysia; D008826:Microbial Sensitivity Tests; D018598:Minisatellite Repeats; D058885:Multilocus Sequence Typing; D011110:Polymorphism, Genetic; D012480:Salmonella Infections / Q000382:microbiology*; D012477:Salmonella enteritidis / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D015047:Zoonoses / Q000382:microbiology*
chemical_list: D004269:DNA, Bacterial
keywords: Antimicrobial resistance; Genotyping; MLVA; Multidrug-resistance; PFGE; Salmonella Enteritidis