title: Livestock-associated methicillin and multidrug resistant S. aureus in humans is associated with occupational pig contact, not pet contact.
abstract: This study aimed to explore the association of livestock-associated S. aureus with occupational pig contact and pet contact. In this cross-sectional study, 1,422 participants (including 244 pig workers, 200 pet-owning workers and 978 control workers) responded to a questionnaire and provided a nasal swab for S. aureus analysis. Resulting isolates were tested for antibiotic susceptibility, the immune evasion cluster (IEC) genes, and multilocus sequence type. Compared with controls, the pig workers demonstrated a greater prevalence of multidrug-resistant S. aureus (MDRSA) [prevalence ratio (PR) = 3.38; 95% CI: 2.07-5.53] and methicillin-resistant S. aureus (MRSA) (PR = 7.42; 95% CI: 3.71-14.83), but the prevalence of MDRSA and MRSA was similar in pet-owning workers and controls. There was a positive relation of frequency of pig contact with prevalence of MDRSA and MRSA carriage. Only pig workers carried MDRSA CC9 (16 isolates) and MRSA CC9 (16 isolates), and all of these isolates were tetracycline resistant and absent of IEC genes. These findings suggest that livestock-associated MRSA and MDRSA(CC9, IEC-negative, tetracycline-resistant) in humans is associated with occupational pig contact, not pet contact, and support growing concern about antibiotics use in pig farms and raising questions about the potential for occupational exposure to opportunistic S. aureus.
authors.affiliation: School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Ye
authors.affiliation: School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Fan
authors.affiliation: School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China.
authors.forename: Weidong
authors.initials: W
authors.lastname: Liu
authors.affiliation: Leliu Hospital of Shunde, Shunde, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Yu
authors.affiliation: School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China.
authors.forename: Junli
authors.initials: J
authors.lastname: Zhou
authors.affiliation: School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China.
authors.forename: Sidong
authors.initials: S
authors.lastname: Chen
authors.affiliation: School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China.
authors.forename: Zhenjiang
authors.initials: Z
authors.lastname: Yao
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D024901:Drug Resistance, Multiple, Bacterial; D000067565:Farmers; D005260:Female; D006801:Humans; D058751:Livestock / Q000382:microbiology*; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000187:drug effects* / Q000235:genetics; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D016273:Occupational Exposure / Q000009:adverse effects*; D011159:Population Surveillance; D015995:Prevalence; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission*; D013211:Staphylococcus aureus / Q000145:classification / Q000187:drug effects* / Q000235:genetics; D055815:Young Adult