Antimicrobial Resistance Through a One Health Lens : Why It Matters in Veterinary Practice

The concept of One Health is no longer theoretical; it is central to modern veterinary decision-making. It recognizes the deep interconnection between human, animal, and environmental health, while promoting interdisciplinary collaboration to address shared health threats¹. For veterinarians, this translates into a broader responsibility that extends beyond treating animals to safeguarding ecosystems and public health. 

Key global challenges impacting One Health include zoonotic diseases, foodborne infections, antimicrobial resistance (AMR), and climate change^1,2,3. Among these, AMR stands out as one of the most complex and urgent threats, directly influencing treatment outcomes in both veterinary and human medicine. 

Antibiotics and the Growing Threat of Resistance 

Antibiotics have long been essential tools in managing bacterial infections in animals due to their efficacy and safety⁴. However, the emergence of AMR has significantly compromised their effectiveness. Of particular concern are multidrug-resistant organisms and pathogens resistant to last-resort antibiotics, such as carbapenem-resistant Enterobacterales and colistin-resistant Escherichia coli¹. 

In veterinary settings, this has direct implications: 

• Reduced treatment success in severe infections  

• Increased morbidity and mortality in livestock and companion animals  

• Threats to animal welfare and productivity  

Beyond clinical outcomes, AMR also impacts food safety and food security, especially in food-producing animals. 

Environmental Dimensions of AMR 

Veterinary antibiotic use does not operate in isolation. Residues of antibiotics and their metabolites enter soil and water systems, altering microbial ecosystems and promoting the selection of resistant genes⁵. This environmental reservoir becomes a critical link in AMR transmission. 

The environment serves as: 

• A reservoir of resistant bacteria  

• A transmission bridge between wildlife, livestock, and humans  

• A selective pressure zone for AMR evolution  

For veterinarians, this highlights the importance of responsible antibiotic usage and waste management practices. 

Mechanisms Driving AMR Spread 

AMR develops through both natural and human-driven processes. While resistance genes exist naturally in microbial communities, their rapid spread is largely driven by antibiotic selection pressure from medical and agricultural use⁴. 

Key mechanisms include: 

• Genetic mutations under antibiotic pressure  

• Horizontal gene transfer via mobile genetic elements¹ 

This ability allows bacteria to rapidly adapt and share resistance traits across species, making control efforts more challenging. 

Multi-Directional Transmission: A One Health Reality 

One of the most critical aspects of AMR is its ability to move across sectors without boundaries. Resistance developed in one domain can easily spill over into others. 

Examples include: 

• Transmission from animals to humans via food, water, and environment  

• Spread from human sewage and agricultural runoff into ecosystems  

• Reverse zoonotic transmission from humans back to animals^1,5 

This interconnected transmission cycle reinforces that AMR is not a localized issue, it is a shared global problem. 

Practical Takeaways for Veterinarians 

From a clinical and field perspective, veterinarians play a pivotal role in mitigating AMR: 

• Judicious antibiotic selection and use  

• Awareness of environmental impact  

• Recognizing zoonotic transmission risks  

• Integrating One Health principles into practice   

Conclusion 

AMR exemplifies the complexity of One Health challenges. Its emergence, spread, and persistence are shaped by interactions between animals, humans, and the environment. For veterinarians, adopting a One Health approach is no longer optional, it is essential for ensuring sustainable animal health, protecting public health, and preserving antibiotic efficacy for the future. 

References 

1. Zhang Q, Beyi AF, Yin Y. Zoonotic and antibiotic-resistant Campylobacter: A view through the One Health lens. One Health Advances. 2023 Mar 30;1(1):4. https://link.springer.com/content/pdf/10.1186/s44280-023-00003-1.pdf 

2. Zinsstag J, Crump L, Schelling E, Hattendorf J, Maidane YO, Ali KO, Muhummed A, Umer AA, Aliyi F, Nooh F, Abdikadir MI. Climate change and one health. FEMS microbiology letters. 2018 Jun;365(11):fny085. https://academic.oup.com/femsle/article-pdf/365/11/fny085/25086213/fny085.pdf 

3. Hernando-Amado S, Coque TM, Baquero F, Martínez JL. Defining and combating antibiotic resistance from One Health and Global Health perspectives. Nature microbiology. 2019 Sep;4(9):1432-42. https://www.researchgate.net/profile/Sara-Hernando-Amado/publication/335337005_Defining_and_combating_antibiotic_resistance_from_One_Health_and_Global-Health_perspectives/links/5d7123f4299bf1cb8088bd73/Defining-and-combating-antibiotic-resistance-from-One-Health-and-Global-Health-perspectives.pdf 

4. McEwen SA, Collignon PJ. Antimicrobial Resistance: a One Health perspective. Microbiol Spectr. 2018;6(2). https://doi.org/10.1128/micro biolspec.ARBA-0009-2017. 

5. Larsson DJ, Flach CF. Antibiotic resistance in the environment. Nature Reviews Microbiology. 2022 May;20(5):257-69. https://www.nature.com/articles/s41579-021-00649-x.pdf