The prevalence and influencing factors of methicillin-resistant Staphylococcus aureus carriage in people in contact with livestock: A systematic review

Am J Infect Control. 2015 May 1;43(5):469-75. doi: 10.1016/j.ajic.2014.12.009. Epub 2015 Feb 10.


Background: Methicillin-resistant Staphylococcus aureus (MRSA) is becoming a serious epidemic worldwide. Recently, studies have shown that people in contact with livestock may have a greater chance of MRSA carriage. We aimed to establish the prevalence of MRSA among people in contact with livestock and review the factors influencing MRSA carriage.

Methods: We systematically examined published epidemiologic studies on MRSA prevalence in people in contact with livestock using Pubmed, Medline, Embase, Ovid, and the Cochrane Library. Prevalence estimates were pooled using a random-effects model. Study heterogeneity was assessed using Q statistics and quantified with I(2) statistics.

Results: Thirty-three eligible studies were included in this systematic review. Prevalence of MRSA ranged from 0.0%-85.8%. The pooled prevalence estimate of MRSA was 14.2% (95% confidence interval, 9.1%-20.1%) for people in contact with livestock. Substantial heterogeneity in eligible studies was noted (χ(2) = 1,025; P < .001; I(2) = 96.9%). Subgroup analysis showed the prevalence of MRSA was high in people from Europe (15.9%), farmers (18.2%), and by longitudinal study design (38.9%). Animal contact and intensity of animal contact were associated with increased risk of MRSA carriage.

Conclusion: Our findings suggest that there may be transmission of MRSA between animals and humans.

Keywords: Epidemiology; Human; Livestock; MRSA.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review
  • Systematic Review

MeSH terms

  • Animals
  • Carrier State / epidemiology*
  • Carrier State / microbiology
  • Humans
  • Livestock*
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification*
  • Occupational Exposure*
  • Prevalence
  • Staphylococcal Infections / epidemiology*
  • Staphylococcal Infections / microbiology