China bans colistin as a feed additive for animals

Last year, the first mobile mechanism of colistin resistance, termed MCR-1, was reported in China. 1 Liu YY Wang Y Walsh TR et al. Emergence of plasmid-mediated colistin resistance mechanism MCR-1 in animals and human beings in China: a microbiological and molecular biological study. Lancet Infect Dis. 2016; 16: 161-168 Summary Full Text Full Text PDF PubMed Scopus (3334) Google Scholar Subsequently, MCR-1 has been reported in more than 30 countries or regions, spanning four continents. 2 McGann P Snesrud E Maybank R et al. Escherichia coli harboring mcr-1 and blaCTX-M on a novel IncF plasmid: first report of mcr-1 in the United States. Antimicrob Agents Chemother. 2016; 60: 4420-4421 Crossref PubMed Scopus (301) Google Scholar , 3 Skov RL Monnet DL Plasmid-mediated colistin resistance (mcr-1 gene): three months later, the story unfolds. Eurosurveillance. 2016; 21: 1 Crossref Scopus (249) Google Scholar , 4 Schwarz S Johnson AP Transferable resistance to colistin: a new but old threat. J Antimicrob Chemother. 2016; (published online June 24.)https://doi.org/10.1093/jac/dkw274 Crossref Scopus (238) Google Scholar Jianzhong Shen and colleagues, 5 Shen Z Wang Y Shen Y Shen J Wu C Early emergence of mcr-1 in Escherichia coli from food-producing animals. Lancet Infect Dis. 2016; 16: 293 Summary Full Text Full Text PDF PubMed Scopus (190) Google Scholar in a retrospective study, reported that MCR-1 was present in Escherichia coli as far back as the mid-1980s, and suggested that the use of colistin in animal feed has probably accelerated the dissemination of MCR-1 in animals and, subsequently, human beings. The predominance of MCR-1 on farms and in livestock, compared with in normal human flora and hospital infections, supports this theory (unpublished data).