title: Comparison of livestock-associated and health care-associated MRSA-genes, virulence, and resistance.
abstract: Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) may colonize and infect humans with close contact to pigs. We compared phenotypic and genotypic differences in resistance and virulence of LA-MRSA isolates from farms and farmers with hospital-acquired methicillin-resistant S. aureus (HA-MRSA) and assessed carriage rates. Samples from pigs (n=330), occupationally exposed personnel (n=63), the farm environment (n=134), and hospital patients (n=220) were obtained. Approximately 50% (166/330) of pigs were MRSA positive. All LA-MRSA were resistant to tetracycline, compared to only 8% of HA-MRSA (P<0.001). In contrast, HA-MRSA isolates showed significantly higher resistance rates to quinolones (81% versus 7%; P<0.001). All strains isolated from occupationally exposed personnel (61.9%; 39/63) belonged to CC398. HA-MRSA isolates were diversely distributed, with predominance of CC5 (62.7%). Human strains carried significantly more virulence genes than porcine strains, especially exotoxins (P<0.001) and immune-evasion cluster genes (P<0.001). There were significant differences in resistance patterns and recognized genotypic virulence loci between LA-MRSA and HA-MRSA.
authors.affiliation: Department of Infectious Diseases, Heidelberg University Hospital, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany. Electronic address: nico.mutters@med.uni-heidelberg.de.
authors.forename: Nico T
authors.initials: NT
authors.lastname: Mutters
authors.affiliation: Department of Infectious Diseases, Heidelberg University Hospital, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany; Department for Veterinary Clinical Sciences, Justus-Liebig-University Gießen, Frankfurter Straße 112 D-35392 Gießen, Germany.
authors.forename: Christian P
authors.initials: CP
authors.lastname: Bieber
authors.affiliation: Department of Infectious Diseases, Heidelberg University Hospital, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany; Department for Veterinary Clinical Sciences, Justus-Liebig-University Gießen, Frankfurter Straße 112 D-35392 Gießen, Germany.
authors.forename: Catherine
authors.initials: C
authors.lastname: Hauck
authors.affiliation: Department for Veterinary Clinical Sciences, Justus-Liebig-University Gießen, Frankfurter Straße 112 D-35392 Gießen, Germany.
authors.forename: Gerald
authors.initials: G
authors.lastname: Reiner
authors.affiliation: Department of Infectious Diseases, Heidelberg University Hospital, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
authors.forename: Veronika
authors.initials: V
authors.lastname: Malek
authors.affiliation: Department of Infectious Diseases, Heidelberg University Hospital, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Frank
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002353:Carrier State / Q000382:microbiology* / Q000662:veterinary*; D003428:Cross Infection / Q000382:microbiology*; D003430:Cross-Sectional Studies; D024881:Drug Resistance, Bacterial; D006761:Hospitals; D006801:Humans; D058751:Livestock; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects* / Q000302:isolation & purification / Q000472:pathogenicity; D016273:Occupational Exposure; D013203:Staphylococcal Infections / Q000382:microbiology* / Q000662:veterinary*; D013552:Swine; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D037521:Virulence Factors
keywords: CC398; Genotyping; Infection control; Livestock; MRSA; Pig farms; Transmission