To paraphrase Anthelme Brillat-Savarin, “we are what we eat”—Especially when it comes to antimicrobials and food-producing animals.
The world of antimicrobial resistance is constantly evolving as efforts to combat the spread of resistant bugs are being explored. Recent reports from the United Kingdom are drawing attention to the 200 patients found to have infections from the highly resistant Candida auris fungus across 55 hospitals. Fungal infections, in general, are increasingly getting attention as there has been a steady rise in deaths associated with invasive infections. These outbreaks are particularly difficult to control and strain infection control efforts, especially in resource-limited facilities.
What makes controlling and treating antimicrobial resistant (AMR) pathogens so challenging is that there are so many components to the proliferation of these organisms. Antimicrobial resistance has a range of culprits from medical practices, antimicrobial stewardship, medical tourism, agriculture, etc. While we work to address the healthcare aspect of antimicrobial resistance, a new report is drawing attention to the role of consumption of antimicrobial agents and their role in the occurrence of resistance.
The European Center for Disease Control and Prevention (ECDC), European Food Safety Authority (EFSA), and European Medicines Agency (EMA) recently released a report regarding the consumption of antimicrobial agents and occurrence of antimicrobial resistance in bacteria from humans and food-producing animals. Their findings revealed some interesting trends in antimicrobial consumption (AMC) during the surveillance period from 2013 to 2015 in the European Union (EU).
Aiming to study the associations between AMC and AMR, they found that in 2014, the average AMC was higher in animals (152 mg/kg) than in humans (124 mg/kg), but the opposite applied to the median AMC (67 and 118 mg/kg). Researchers found that in 18 of 28 countries, AMC was lower in animals than humans. Moreover, “univariate analysis showed statistically-significant associations between AMC and AMR for fluoroquinolones and Escherichia coli (E. coli) in both sectors, for 3rd- and 4th-generation cephalosporins and E. coli in humans, and tetracyclines and polymyxins and E. coli in animals. In food-producing animals, stronger and more consistent associations between AMC and AMR were more frequently observed for indicator E. coli than for Salmonella spp.” In addition, they found that when food-producing animals consumed macrolides, there was a significant association with macrolide-resistant Campylobacter coli in both animals and humans. Overall, this analysis points to the relationship between AMC and resistance across species.
Drawing on the ‘One Health’ model, these results support the notion that the health of animals and humans are interconnected and that stewardship in one will inherently impact resistance in the other. This analysis also highlights the need for continued research to understand the dynamics of antimicrobial resistance and the role of antimicrobial consumption and stewardship in this web. Further research is needed to track the microbial conversion to resistance, horizontal and vertical transmission, and what kind of stressors are strongest in facilitating the development of resistant genes.
One particular component to this report is that it makes use of multiple surveillance and monitoring systems across the EU. This aspect draws attention to the importance of international surveillance and coordination. A problem as large as AMR will require international cooperation across many sectors.
Recently, the Centers for Disease Control and Prevention (CDC) announced their investment of $77 million to combat existing and emerging antibiotic resistance, which is a significant step in the battle of the resistant bug. The ECDC report also points to widespread efforts to better understand the adversarial threat that is AMR and the role of food-producing animals and antimicrobial consumption.
Perhaps we really are what we eat?