title: Livestock-associated MRSA ST398 carriage in pig slaughterhouse workers related to quantitative environmental exposure.
abstract: OBJECTIVE
  To assess livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) carriage among workers in pig slaughterhouses and assess associated risk factors, including occupational exposure to LA-MRSA.
  
  
  METHODS
  A cross-sectional study in three Dutch pig slaughterhouses was undertaken. Nasal swabs of participants were taken. Nasal swabs and surface wipes, air and glove samples were screened for presence of methicillin-resistant Staphylococcus aureus (MRSA). MRSA was quantitatively determined on gloves and in air samples by culturing and real-time PCR.
  
  
  RESULTS
  11 of 341 (3.2%) participants were identified as nasal MRSA carriers. MRSA-positive workers were predominantly found at the start of the slaughter process. Major risk factors for carriage were working in the lairage and working in the scalding and dehairing area. Most nasal isolates (73%) belonged to the LA-MRSA clone ST398. MRSA ST398-positive environmental samples were found throughout the slaughter process. A clear decrease was seen along the slaughterline in the number of MRSA-positive samples and in the MRSA amount per sample.
  
  
  CONCLUSIONS
  This study showed that working in the lairage area or scalding and dehairing area were the major risk factors for MRSA carriage in pig slaughterhouse workers, while the overall prevalence of MRSA carriage is low. Occupational exposure to MRSA decreased along the slaughterline, and the risk of carriage showed a parallel decrease.
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, PO BOX 80178, 3508 TD Utrecht, The Netherlands. m.e.h.bos@uu.nl
authors.forename: Maarten J
authors.initials: MJ
authors.lastname: Gilbert
authors.forename: Marian E H
authors.initials: ME
authors.lastname: Bos
authors.forename: Birgitta
authors.initials: B
authors.lastname: Duim
authors.forename: Bert A P
authors.initials: BA
authors.lastname: Urlings
authors.forename: Lourens
authors.initials: L
authors.lastname: Heres
authors.forename: Jaap A
authors.initials: JA
authors.lastname: Wagenaar
authors.forename: Dick J J
authors.initials: DJ
authors.lastname: Heederik
mesh_terms: D000003:Abattoirs; D000328:Adult; D000368:Aged; D000818:Animals; D002353:Carrier State / Q000453:epidemiology*; D018929:Cell Culture Techniques; D003430:Cross-Sectional Studies; D006801:Humans; D058751:Livestock / Q000382:microbiology*; D055624:Methicillin-Resistant Staphylococcus aureus; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D009666:Nose / Q000382:microbiology; D016273:Occupational Exposure; D009790:Occupations; D060888:Real-Time Polymerase Chain Reaction; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D013552:Swine / Q000382:microbiology*; D055815:Young Adult