title: Identification of livestock-associated methicillin-resistant Staphylococcus aureus isolates in Korea and molecular comparison between isolates from animal carcasses and slaughterhouse workers.
abstract: This study was undertaken to screen methicillin-resistant Staphylococcus aureus (MRSA) in animal carcasses and slaughterhouse workers and characterize MRSA isolates identified during 2010-2012 in Korea. A total of 830 (16.4%) S. aureus and 65 (1.3%) MRSA were isolated from 9669 carcass samples. MRSA was more frequently detected in chicken carcasses (1.2%) than in cattle (0.3%) and pig carcasses (0.6%). The prevalence of MRSA in workers was 6.9% (4/58) in chicken slaughterhouse workers, but no MRSA was detected in pig and cattle slaughterhouse workers (0/41). Two different lineages of MRSA were identified (i.e., human-associated type [ST5, ST59, and ST72] and livestock-associated [LA] type [ST398, ST541, and ST692]); only LA MRSA was observed in chicken carcasses, whereas both types were found in cattle and pig carcasses and workers. All human-associated MRSA isolates carried enterotoxin and/or leukotoxin genes, whereas LA MRSA types did not carry these genes, except ST692 type. However, all LA MRSA isolates were multiresistant, whereas human-associated types were susceptible or resistant to fewer than two antimicrobials except ST5. Furthermore, one or more resistance genes were attributed for resistance to aminoglycosides (aac(6')-Ie-aph(2″), ant(4')-Ia, and aph(3')-IIIa), tetracycline [tet(K), tet(L), tet(M), and tet(S)], macrolide-lincosamide-streptogramin B (ermA, ermB, ermC, and ermT), lincosamide [lnu(B)], phenicol-lincosamide-oxazolidinone-pleuromutilin-streptogramin A (cfr), chloramphenicol (fexA), and fusidic acid [fus(C)]. To our knowledge, this is the first report of tet(S) gene in MRSA isolates and first detection of a unique (ST692) type of MRSA in occupational workers. Detection of new types of human-associated and LA MRSA with multiple resistance and virulence genes in food animal products constitutes a potential threat to public health.
authors.affiliation: 1 Bacterial Disease Division, Animal and Plant Quarantine Agency , Anyang-si, Gyeonggi-do, Korea.
authors.forename: Dong Chan
authors.initials: DC
authors.lastname: Moon
authors.forename: Migma Dorji
authors.initials: MD
authors.lastname: Tamang
authors.forename: Hyang-Mi
authors.initials: HM
authors.lastname: Nam
authors.forename: Jin-Ha
authors.initials: JH
authors.lastname: Jeong
authors.forename: Geum-Chan
authors.initials: GC
authors.lastname: Jang
authors.forename: Suk-Chan
authors.initials: SC
authors.lastname: Jung
authors.forename: Yong-Ho
authors.initials: YH
authors.lastname: Park
authors.forename: Suk-Kyung
authors.initials: SK
authors.lastname: Lim
mesh_terms: D000003:Abattoirs; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002417:Cattle; D002645:Chickens; D005839:Gentamicins / Q000494:pharmacology; D006801:Humans; D007612:Kanamycin / Q000494:pharmacology; D058751:Livestock / Q000382:microbiology*; D008460:Meat / Q000382:microbiology*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D008826:Microbial Sensitivity Tests; D056910:Republic of Korea; D013203:Staphylococcal Infections / Q000382:microbiology*; D013552:Swine; D014774:Virulence
chemical_list: D000900:Anti-Bacterial Agents; D005839:Gentamicins; D007612:Kanamycin