To the Editor:
We thank Liu et al
1
for their meta-analysis on the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) carriage among persons in contact with livestock. Although the results are interesting, the extreme heterogeneity (I2 = 96.9%) makes it questionable whether a pooled prevalence estimate offers a meaningful statistic. The extreme heterogeneity is further demonstrated by the authors' forest plot. Confidence intervals on prevalence estimates above the summary estimate are extremely wide compared with those below the summary estimate. In addition, 2 studies included in the meta-analysis report zero prevalence; 1 study reports 85% prevalence, a considerable disparity. Some results require further explanation. For example, the odds ratio for smoking was significantly <1, suggesting that smoking is protective against MRSA carriage. Based on their results, the authors conclude that there may be transmission of MRSA between animals and humans. If this conclusion is correct, it begs the question of whether the transmitted MRSA strains are human-associated strains. If the transmission is a livestock-associated strain, is it a human health concern? Further research is needed to address these important questions.Reference
- 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; 43: 469-475
Article info
Publication history
Published online: September 22, 2015
Footnotes
Conflicts of interest: None to report.
Identification
Copyright
© 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
