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

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 I2 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 (χ2 = 1,025; P < .001; I2 = 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.