title: Factors associated with the occurrence of MRSA CC398 in herds of fattening pigs in Germany.
abstract: BACKGROUND
  The purpose of this study was to investigate the prevalence of MRSA in herds of fattening pigs in different regions of Germany, and to determine factors associated with the occurrence of this pathogen. For this purpose pooled dust samples were collected, and a questionnaire covered information regarding herd characteristics and management practices. Samples were pre-enriched in high-salt medium followed by selective enrichment containing cefoxitin/aztreonam, and culturing. Presumptive colonies were confirmed by multiplex-PCR targeting nuc-, mecA- and 16S rRNA-genes. Isolates were spa- and SCCmec-, and in selected cases, multilocus sequence-typed. Susceptibilities to 13 antimicrobials were determined by broth microdilution. Statistical analysis was carried out using backward stepwise logistic regression to calculate odds ratios with the MRSA test result as the outcome and herd characteristics as categorical covariates.
  
  
  RESULTS
  Overall, 152 of 290 (52%) fattening pig farms tested positive for MRSA. The prevalence in the east, north- and south-west of Germany ranged from 39 to 59%.t011 (66%) and t034 (23%) were the most commonly identified spa-types, and 85% of isolates carried SCCmec Type V. Identified spa-types were all associated with clonal complex CC398. Susceptibility testing revealed that all isolates were resistant to tetracycline. High resistance rates were also found for sulfamethoxazole/trimethoprim (40%), and quinupristin/dalfopristin (32%). In addition, 83% of strains displayed multidrug resistant (> 3 substance classes) phenotypes.Logistic regression revealed herd size (large farms OR: 5.4; CI: 2.7-11.2; p < 0.05), and production type (wean-to-finish OR: 4.0; CI: 1.6-10.4; p < 0.05) as risk factors associated with a positive MRSA finding in fattening pig operations.
  
  
  CONCLUSIONS
  MRSA CC398 is widely distributed among herds of fattening pigs in Germany. Farm management plays a crucial role in the dissemination of MRSA with herd size, and production type representing potential major indicators.
authors.affiliation: Federal Institute for Risk Assessment, Berlin, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Alt
authors.forename: Alexandra
authors.initials: A
authors.lastname: Fetsch
authors.forename: Andreas
authors.initials: A
authors.lastname: Schroeter
authors.forename: Beatriz
authors.initials: B
authors.lastname: Guerra
authors.forename: Jens A
authors.initials: JA
authors.lastname: Hammerl
authors.forename: Stefan
authors.initials: S
authors.lastname: Hertwig
authors.forename: Natalja
authors.initials: N
authors.lastname: Senkov
authors.forename: Anna
authors.initials: A
authors.lastname: Geinets
authors.forename: Christine
authors.initials: C
authors.lastname: Mueller-Graf
authors.forename: Juliane
authors.initials: J
authors.lastname: Braeunig
authors.forename: Annemarie
authors.initials: A
authors.lastname: Kaesbohrer
authors.forename: Bernd
authors.initials: B
authors.lastname: Appel
authors.forename: Andreas
authors.initials: A
authors.lastname: Hensel
authors.forename: Bernd-Alois
authors.initials: BA
authors.lastname: Tenhagen
mesh_terms: D000822:Animal Husbandry / Q000592:standards; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology; D004391:Dust / Q000032:analysis; D005858:Germany / Q000453:epidemiology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D008826:Microbial Sensitivity Tests; D058889:Molecular Typing; D015995:Prevalence; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D011795:Surveys and Questionnaires; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology* / Q000382:microbiology
chemical_list: D000890:Anti-Infective Agents; D004391:Dust
references.citation: Antimicrob Agents Chemother. 2008 Oct;52(10):3817-9
references.pmid: 18663024
references.citation: J Clin Microbiol. 2000 Mar;38(3):1008-15
references.pmid: 10698988
references.citation: Emerg Infect Dis. 2007 Feb;13(2):255-8
references.pmid: 17479888
references.citation: Vet Microbiol. 2008 Jan 25;126(4):383-9
references.pmid: 17765409
references.citation: Vet Rec. 2009 Nov 14;165(20):589-93
references.pmid: 19915190
references.citation: J Clin Microbiol. 1999 Nov;37(11):3556-63
references.pmid: 10523551
references.citation: Epidemiol Infect. 2009 May;137(5):700-8
references.pmid: 18947444
references.citation: Microb Drug Resist. 2008 Dec;14(4):307-10
references.pmid: 19025385
references.citation: Ned Tijdschr Geneeskd. 2006 Nov 4;150(44):2442-7
references.pmid: 17131705
references.citation: Emerg Infect Dis. 2006 Dec;12(12):1939-41
references.pmid: 17326948
references.citation: Vet Microbiol. 2007 Jun 21;122(3-4):384-6
references.pmid: 17467199
references.citation: PLoS One. 2009;4(1):e4258
references.pmid: 19145257
references.citation: J Antimicrob Chemother. 2009 Dec;64(6):1156-64
references.pmid: 19808235
references.citation: Vet Microbiol. 2010 Feb 24;141(1-2):96-102
references.pmid: 19740613
references.citation: Emerg Infect Dis. 2009 Mar;15(3):452-3
references.pmid: 19239762
references.citation: Vet Microbiol. 2008 Apr 30;128(3-4):298-303
references.pmid: 18023542
references.citation: J Antimicrob Chemother. 2009 Sep;64(3):660-2
references.pmid: 19608580
references.citation: Appl Environ Microbiol. 2010 Feb;76(3):652-8
references.pmid: 20023093
references.citation: Zoonoses Public Health. 2011 Jun;58(4):252-61
references.pmid: 20630047
references.citation: Euro Surveill. 2010 Apr 22;15(16):
references.pmid: 20430001
references.citation: PLoS One. 2009 Aug 27;4(8):e6800
references.pmid: 19710922
references.citation: J Infect Chemother. 2007 Apr;13(2):79-86
references.pmid: 17458674
references.citation: Ann Clin Microbiol Antimicrob. 2006 Nov 10;5:26
references.pmid: 17096847
references.citation: Appl Environ Microbiol. 2011 May;77(9):3052-60
references.pmid: 21378035
references.citation: J Clin Microbiol. 2005 Oct;43(10):5026-33
references.pmid: 16207957
references.citation: PLoS One. 2010 Jun 08;5(6):e10990
references.pmid: 20544020
references.citation: BMC Vet Res. 2011 Jul 26;7:41
references.pmid: 21791057
references.citation: J Antimicrob Chemother. 2003 Feb;51(2):419-21
references.pmid: 12562714
references.citation: Vet Microbiol. 2007 Jun 21;122(3-4):366-72
references.pmid: 17367960
references.citation: J Antimicrob Chemother. 2010 Apr;65(4):619-25
references.pmid: 20164198