Genomic screening of antimicrobial resistance markers in Campylobacter jejuni and Campylobacter coli demonstrates stability of resistance over an 18 year period

Abstract P4

Presenter: Arnoud Van Vliet (University of Surrey)

Introduction

Campylobacter jejuni and Campylobacter coli are important bacterial sources of foodborne illness. There are concerns about the high levels of antimicrobial resistance (AMR) in C. jejuni and C. coli in food animal production, especially poultry. The USA and UK both have instigated large-scale whole genome sequencing-based surveillance programs for Campylobacter. Here we have combined genome sequences from these surveillance programs and historical samples to compare predicted prevalence of antibiotic resistance between the UK and USA from 2001-2018.

Methods

Genome sequences and metadata (source, year and country) were obtained for 32,256 C. jejuni and 8,776 C. coli genomes. Antibiotic resistance markers were identified using the NCBI AMRfinder software. AMR profiles were compiled based on the most common antibiotics used with Campylobacter (aminoglycosides, macrolides, quinolones and tetracycline).

Results

A larger proportion of C. coli isolates contained resistance markers (68% vs 53% for C. jejuni), with 15% of C. coli isolates being multi-drug resistant (MDR) compared to only 2% of C. jejuni. Levels of resistance to the aminoglycosides, macrolides, quinolones and tetracycline were mostly stable from 2001-2018 in both C. jejuni and C. coli, but differences were observed between the UK and USA isolates. There were higher levels of aminoglycoside- and tetracycline-resistance in the USA isolates for both C. coli and C. jejuni. In contrast, quinolone resistance was higher in UK C. jejuni isolates. There were no clear links between the resistance and an isolation source, but specific MLST clonal complexes (e.g. ST-353/464) were almost universally resistant to quinolones.

Conclusion

This is the first large-scale comparison of antibiotic resistance levels in UK and USA Campylobacter isolates. Although different, the levels of Campylobacter antimicrobial resistance remain relatively stable in both the UK and USA over time. Such stability of antibiotic resistance does suggest that antimicrobial stewardship and restricted usage may help contain further expansion of antibiotic resistance levels in Campylobacter, but are unlikely to reduce it in the short term.

About the presenter

https://www.surrey.ac.uk/people/arnoud-van-vliet

Presenting in Speaking session 2 - Pathogenesis