Extended spectrum cephalosporin (ESC) resistant Escherichia coli: Trends and seasonality in the Netherlands from 2014 to 2022

Background

Antimicrobial resistance (AMR) in livestock and the environment likely contribute to the prevalence of AMR in humans with potential detrimental effects on human health. As such, annual mandatory monitoring of AMR in livestock occurs within the European Union (EU), according to harmonised methods. Extended-spectrum cephalosporins-resistant (ESC-resistant) Escherichia coli, including extended-spectrum β-lactamases (ESBL), AmpC β-lactamases (AmpC) and carbapenemase producing E. coli, are considered of particular importance and are therefore included in the monitoring program.

Methods

Using results from the annual monitoring of ESC-resistant E. coli from 2014–2022, trends in prevalence per animal sector were determined over the complete time period, as well as potential seasonal effects.

Results

During these nine years, significant changes were observed in the prevalence of ESC-resistant E. coli, in broilers, dairy cattle and veal calves, while no changes in prevalence were seen in slaughter pigs. Furthermore, the prevalence of ESC-resistant E. coli is positively correlated with warmer seasons (summer and autumn) for both dairy cattle and veal calves, while no associations were found for broilers and slaughter pigs. While temperature itself may play a role in the prevalence of ESC-resistant E. coli, other factors affecting the selective landscape, such as antibiotic usage, will also play a role.

Conclusion

A combined analysis of antimicrobial usage and prevalence of ESC-resistant E. coli through the year, both in livestock and human samples, would be an interesting follow-up of this study.