Enterobacteriaceae and Aeromonas species in retail foods: genotypes associated with antimicrobial resistance

Abstract

Bacterial foodborne pathogens impart a significant burden on public health and economies. This includes well-established hazards such as Enterobacteriaceae, and neglected genera such as Aeromonas. One major concern within this realm of public safety is the proliferation and dissemination of antimicrobial resistance within foodborne bacteria. Enterobacteriaceae are an important group that act as reservoirs for AMR genes, and their dissemination, within food systems.

This study characterised Enterobacteriaceae and Aeromonas isolates within retail foods on sale in England. Furthermore, a subset of multi-drug resistant Enterobacteriaceae and all Aeromonas isolates were subjected to comparative genomic analyses, with an emphasis on antimicrobial resistance.

This work revealed notable phenotypes relevant to food safety, including multi-drug resistance, present within foodborne examples of Enterobacteriaceae and Aeromonas. These resistance phenotypes broadly aligned with resistance genes present, such as extended spectrum beta-lactamases and carbapenemases. Furthermore, notable plasmids were present within the sub-set of sequenced Enterobacteriaceae isolates, which harboured a wide range of genes relevant to antimicrobial and environmental resistance, virulence, and plasmid persistence.

These findings highlight the public health threat that foodborne Enterobacteriaceae present and supports a role for food as an important vector for Aeromonas transmission. Findings support a need for increased surveillance efforts by the food industry on AMR Enterobacteriaceae to contribute to mitigating against the current growing antimicrobial resistance crisis, and the importance of foods as a vector for transmission of pathogenic Aeromonas species.

Date of Award	27 Jun 2024
Original language	English
Awarding Institution	Northumbria University
Supervisor	Edward Fox (Supervisor)