High prevalence and transmission of blaNDM-positive Escherichia coli between farmed ducks and slaughtered meats: An increasing threat to food safety

The emergence of carbapenem-resistant bacteria especially carbapenem-resistant Escherichia coli (CREC) in food animals poses a serious threat to food safety and public health. Reports about the dissemination of carbapenem-resistant bacteria along the food animal production chain are scattered and mainly focus on swine and chicken. Abuse of antibiotics in duck farms is common especially in China which has the largest duck production industry, however, the CREC transmission between farmed ducks and slaughtered meats remains unclear and the role of slaughterhouse in disseminating CREC among duck meats remains largely unknown. Herein, we collected 251 fecal samples from five typical duck farms along with 125 slaughtered meat samples (25 from each farm) in the corresponding slaughterhouse in Anhui Province, China, in December 2018. All samples were screened for CREC isolates which were analyzed for the presence of carbapenemase genes and colistin resistance gene mcr. The resistance profiles, transferability, pulsed-field gel electrophoresis (PFGE), whole-genome sequencing and phylogenetic analysis of the CREC isolates from both ducks and meats were further characterized. This is the first report presenting the high prevalence of bla