Genomic approach to transmission and compartmentalization of extended-spectrum cephalosporin resistance in Enterobacteriaceae from animals and humans (TransComp-ESC-R)




This project studied the epidemiology of resistance to a critically important group of antibiotics called extended-spectrum cephalosporins (ESCs) in humans, animals and food. It showed that the multiplication, transmission and host adaptation of major bacterial strains such as the famous E. coli ST131 is only one method by which resistance to ESCs spreads.

Completed project

The study has identified specific types of ESC resistance plasmids (genetic elements which can move from one bacterium to another), which are spreading very actively in bacterial populations from humans and animals (including wildlife), from the local to the international level and even between Europe and North America.

By comparing bacteria with and without ESC-resistance plasmids the researchers have discovered new interactions between plasmids and their host bacterium. In one case, these interactions may be associated with the regulation of chromosomal genes by plasmid genes not related to antimicrobial resistance. In another case, an antimicrobial resistance gene (mcr) other than for ESC but frequently located on the same plasmid was shown to facilitate the establishment and colonization of the gut by bacteria. In both cases, these interactions are thought to increase the success of ESC resistance plasmids in bacterial populations.

Finally, the researchers also showed that the use of antimicrobials increases the persistence of ESC-resistant bacteria in cattle. They developed mathematical models which allow to predict and quantify this effect. Overall, this study has generated new information on the epidemiology of ESC resistance and mathematical models which will be of great use for both scientists and policy makers in the fight against antimicrobial resistance.

Project partners

  • Patrick Boerlin, University of Guelph, Canada (Coordinator)
  • Richard Bonnet, Université d’Auvergne, France
  • Jean-Yves Madec, National Agency for Food, Environmental and Occupational Health & Safety (ANSES), France
  • Michael Mulvey, University of Manitoba, Canada
  • Stefan Schwarz, Friedrich-Loeffler-Institut, Germany
  • James Wood, University of Cambridge, United Kingdom
  • Alison Mather, University of Cambridge, United Kingdom
  • Heike Kaspar, Federal Office of Consumer Protection and Food Safety, Germany