Livestock-associated MRSA in household members of pig farmers: transmission and dynamics of carriage, a prospective cohort study

• Published in: PloS one 2015-05, Vol.10 (5), p.e0127190-e0127190
• Main Authors: van Cleef, Brigitte A G L, van Benthem, Birgit H B, Verkade, Erwin J M, van Rijen, Miranda M L, Kluytmans-van den Bergh, Marjolein F Q, Graveland, Haitske, Bosch, Thijs, Verstappen, Koen M H W, Wagenaar, Jaap A, Bos, Marian E H, Heederik, Dick, Kluytmans, Jan A J W
• Format: Article
• Language: English
• Subjects: Agriculture; Animals; Carrier State - epidemiology; Cell adhesion & migration; Cohort analysis; CVI Infectiebiologie; CVI Infection Biology; Disease transmission; Diseases; Distribution; Drug resistance; Farm buildings; Farmers; Farms; Hogs; Households; Humans; Infectiebiologie; Infection Biology; Intensive farming; Laboratories; Livestock; Livestock - microbiology; Methicillin; Methicillin-Resistant Staphylococcus aureus - isolation & purification; Netherlands - epidemiology; Nose - microbiology; Oropharynx - microbiology; Penicillin; Prospective Studies; Staphylococcal Infections - epidemiology; Staphylococcal Infections - prevention & control; Staphylococcal Infections - transmission; Staphylococcal Infections - veterinary; Staphylococcus aureus; Staphylococcus aureus infections; Staphylococcus infections; Statistical analysis; Statistics; Swine; Swine - microbiology; Weaning
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0127190

This prospective cohort study describes carriage of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in household members from 49 farrowing pig farms in the Netherlands (2010-2011). Of 171 household members, 4% were persistent MRSA nasal carriers, and the MRSA prevalence on any given sampling moment was 10% (range 7-11%). Working in the stables (of which 98% was MRSA-positive, prevalence ratio (PR) = 2.11 per 10 hours), working with sows (PR=1.97), and living with an MRSA-positive pig farmer (PR=4.63) were significant determinants for MRSA carriage. Significant protective factors were carriage of methicillin-susceptible Staphylococcus aureus (MSSA) (PR=0.50), and wearing a facemask when working in the stables (37% decreased prevalence). All MRSA strains during the study period were known livestock-associated types. The bacteriophage φ3 was not found in household members. Transmission from pigs and the environment appeared to be important determinants; human-to-human transmission could not sufficiently be differentiated. Wearing a facemask when working in the stables and carriage of MSSA are potential interventional targets.