14.01.2016
Promed - Archive Number: 20160113.3933461
The mcr-1 gene, which encodes transferable resistance to colistin, has been confirmed in comensal Escherichia coli from Italy, in primary production of turkeys.
The 1st confirmed mcr-1-positive isolate is among colistin-resistant isolates detected from the harmonised monitoring programme performed on cecal samples at slaughter in 2014, and aimed at estimating the antimicrobial resistance (AMR) prevalence in major zoonotic (e.g. Salmonella, Campylobacter jejuni) and indicator commensal bacteria (e.g.E. coli), according to the Decision 2013/652/EU.
Isolates with minimum inhibitory concentrations (MIC) for colistin above the epidemiological cutoff had already been reported to the National Competent Authority and to the European Food Safety Authority (EFSA) according to the EU legislation. The National Reference Laboratory for Antimicrobial Resistance, IZSLT, Rome, Italy, has been investigating the genetic basis of colistin resistance.
The 1st isolate with the confirmed mcr-1 gene was whole genome-sequenced in collaboration with the European Union Reference Laboratory for Antimicrobial Resistance (EURL-AR), DTU [Technical University of Denmark]-Food, Denmark. It was a multidrug resistant (SMX-TMP-CIP-TET-CHL-COL-AMP) [sulfamethoxazole-trimethoprim-ciprofloxacin-tetracycline-chloramphenicol-colistin-ampicillin] Sequence Type 30 E. coli, also harbouring the Plasmid Mediated Quinolone Resistance (PMQR) gene qnrB19 (CIP MIC [minimal inhibitory concentration] 0.5 mg/L).
See also: China, colistin resistance