Dynamics of methicillin-resistant Staphylococcus aureus and methicillin-susceptible Staphylococcus aureus carriage in pig farmers: a prospective cohort study.
Our purpose was to determine the dynamics of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) carriage and its determinants in persons working at pig farms, in order to identify targets for interventions. This prospective cohort study surveyed 49 pig farms in the Netherlands on six sampling dates in 1 year (2010-11). Nasal and oropharyngeal swabs were collected, as well as environmental surface samples from stables and house. Of 110 pig farmers, 38% were persistent MRSA nasal carriers. The average cross-sectional MRSA prevalence was 63%. Methicillin-susceptible S. aureus (MSSA) nasal carriage was associated with fewer MRSA acquisitions (prevalence rate (PR) = 0.47, p 0.02). In multivariate analysis, an age of 40-49 years (PR = 2.13, p 0.01), a working week of ≥40 h (PR=1.89, p 0.01), giving birth assistance to sows (PR=2.26, p 0.03), removing manure of finisher pigs (PR=0.48, p 0.02), and wearing a facemask (PR = 0.13, p 0.02) were significantly related with persistent MRSA nasal carriage. A higher MRSA exposure in stables was associated with MRSA in pig farmers (p <0.0001). This study describes a very high prevalence of LA-MRSA carriage in pig farmers, reflecting extensive exposure during work. We identified the possible protective effects of MSSA carriage and of continuously wearing a facemask during work.
Laboratory for Microbiology and Infection Control, Amphia Hospital, Breda, the Netherlands; Laboratory for Medical Microbiology and Immunology, St Elisabeth Hospital, Tilburg, the Netherlands; Centre for Infectious Disease Control Netherlands, National Institute for Public Health and the Environment, Bilthoven, the Netherlands.
B A G L
BA
van Cleef
B H B
BH
van Benthem
E J M
EJ
Verkade
M
M
van Rijen
M F Q
MF
Kluytmans-van den Bergh
L M
LM
Schouls
B
B
Duim
J A
JA
Wagenaar
H
H
Graveland
M E H
ME
Bos
D
D
Heederik
J A J W
JA
Kluytmans
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D002353:Carrier State / Q000382:microbiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D058751:Livestock / Q000382:microbiology; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000302:isolation & purification*; D008875:Middle Aged; D009055:Mouth / Q000382:microbiology; D009426:Netherlands; D009666:Nose / Q000382:microbiology; D011446:Prospective Studies; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission*; D034421:Sus scrofa; D055815:Young Adult
Dynamics of carriage; MRSA; MSSA; ST398; epidemiology; livestock; methicillin-resistant Staphylococcus aureus; methicillin-susceptible Staphylococcus aureus; pigs; the Netherlands