Detection and dissemination of the colistin resistance gene, mcr-1, from isolates and faecal samples in China

J Med Microbiol. 2017 Mar;66(2):119-125. doi: 10.1099/jmm.0.000425. Epub 2017 Mar 6.

Abstract

Purpose: A recently identified colistin resistance gene, mcr-1, has been reported in many countries. In this study, we established a new real-time PCR method to detect it.

Methodology: We used a real-time PCR method to detect the mcr-1 gene in a variety of isolates and faecal samples from 20 provinces and municipal cities in China.

Results: Of the 2330 isolates (from 10 species) screened, 54 (2.3 %) isolates were positive for mcr-1. All of the mcr-1-positive isolates that were identified belonged to Escherichia coli strains, among which 9, 1, and 44 were identified as enteropathogenic E. coli, enteroadherent E. coli, and non-pathogenic E. coli, respectively. The majority of the mcr-1-positive isolates were obtained from farm animals from eight provinces and municipal cities across China. A total of 337 faecal samples, including 229 human and 108 pet animal faecal samples, were also screened for the mcr-1 gene. Of the 337 samples analyzed, six and eight human and pet animal faecal samples were positive for the mcr-1 gene, respectively.

Conclusion: The data demonstrate that the mcr-1 gene is highly prevalent in human and animal populations in China. This occurrence suggests that active surveillance of the mcr-1 gene is imperative in curtailing its spread.

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology
  • China
  • Colistin / pharmacology*
  • DNA, Bacterial / genetics
  • DNA, Bacterial / isolation & purification*
  • Drug Resistance, Bacterial / genetics*
  • Escherichia coli / genetics
  • Escherichia coli / isolation & purification
  • Escherichia coli Proteins / genetics*
  • Escherichia coli Proteins / metabolism
  • Feces / microbiology*
  • Gram-Negative Bacteria / genetics
  • Gram-Negative Bacteria / isolation & purification
  • Humans
  • Real-Time Polymerase Chain Reaction
  • Sensitivity and Specificity

Substances

  • Anti-Bacterial Agents
  • DNA, Bacterial
  • Escherichia coli Proteins
  • MCR-1 protein, E coli
  • Colistin