Development of Rapid Response Gene Profiling for Identification of Antimicrobial Resistance Genes in Enterobacteria from Food Animals and Humans

We propose to establish a three-year collaborative programme between the Veterinary Medicines Directorate (VMD), the Department of Bacterial Diseases at the Veterinary Laboratories Agency (VLA)-Weybridge Laboratory, the Public Health Laboratory Service (PHLS) Laboratory of Enteric Pathogens (LEP) and the Danish Veterinary Institute (DVI) targeted at the development and assessment of a range of rapid, PCR-based tests for the identification of specific resistance genes of importance to animal and human health in Salmonella enterica. <P>
The programme would include the construction of an oligonucleotide array for the identification of specific resistance genes, Class 1 integrons, and mutations conferring resistance to specific antimicrobials such as the fluoroquinolones. In the first instance particular emphasis would be placed on the identification of genes conferring resistance to third-generation cephalosporins (eg, SHV, CMY, CTX-M) and of mutations conferring resistance to quinolone antibiotics. These methods would then be applied to the characterisation of such resistance genes in isolates of S. enterica from humans and food production animals in the respective countries. <P>
Results would be assimilated into existing international European databases such as Enter-Net, Salm-gene, and the recently proposed Pulse-Net Europe. Results would also used as the basis for the development of a more extensive zoonotic molecular antimicrobial resistance database for all EU countries, which would be made accessible to laboratories in all participating countries. If successful this scheme could be expanded to include other key bacterial pathogens such as Campylobacter spp. and Escherichia coli O157.<P>
Work at the VLA and the PHLS would establish the methodology for the research and provide a national baseline for the occurrence and distribution of specific drug resistance genes in S. enterica and the involvement of the DVI would provide an international dimension to the investigation.
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Objective: <OL> <LI>
To develop resistance gene profiling for antimicrobial resistance genes in S. enterica with particular respect to genes conferring resistance to ESBLs. <LI> To develop and extend gyrA Mutational Analysis (GAMA) for the identification of different mutations giving rise to resistance to quinolone antibiotics. <LI> To develop a DNA microarray for specific resistance genes. <LI> To determine the incidence of the particular resistance genes in predetermined panels of drug-resistant isolates of S. enterica from food production animals and humans in England and Wales, and Denmark. <LI> To develop a common database of resistance gene types utilising Bionumerics software, and to establish a collaborative exchange of molecular antimicrobial resistance data between the PHLS LEP, VLA-Weybridge and the DVI, using electronic data transfer. <LI> To establish a rapid response system for the recognition of newly-emerged antimicrobial resistance genes of potential importance to public health in zoonotic pathogens.<LI> To provide useful and timely information on the occurrence of specific antimicrobial resistance genes in S. enterica to Defra, the Veterinary Medicines Directorate (VMD), the VLA, the Food Standards Agency, the Health Protection Agency (HPA), and the DVI. <LI> To incorporate molecular information on the occurrence of antimicrobial resistance genes into existing and proposed international databases for zoonotic bacterial pathogens.