The Global Resistome: How Livestock, Humans, and the Environment Fuel the Rise of Antibiotic Resistance

This article was exclusively written for The European Sting by Ms. Sadia Khalid, a Scientist-Physician (MBBS, MD) at Tallinn University of Technologye. She is affiliated with the International Federation of Medical Students Associations (IFMSA), cordial partner of The Sting. The opinions expressed in this piece belong strictly to the writer and do not necessarily reflect IFMSA’s view on the topic, nor The European Sting’s one.

Antibiotic resistance threatens to undermine decades of progress in medicine, agriculture, and public health. Embracing a robust One Health approach—one that unites human, animal, and environmental health—is crucial for preserving the effectiveness of both current and future antibiotics and safeguarding global health.

Antibiotic resistance (AR) is a complex and rapidly escalating global health threat that affects livestock, humans, and the environment. Its rise is driven by multiple interconnected factors, making it one of the most challenging problems of the 21st century. Estimates warn that, if current trends persist, AR could cause up to 10 million deaths annually by 2050, placing immense pressure on healthcare, food security, and environmental sustainability. Because resistant bacteria and their genes move freely across species and ecosystems, AR is widely regarded as a quintessential One Health issue.

In the One Health framework, humans, animals, and the environment are understood as interdependent systems. Numerous bacterial species—such as E. coli, Salmonella, Campylobacter, and Staphylococcus aureus—carry resistance genes that circulate between people, livestock, wildlife, soil, air, and water. The primary drivers of AR include the overuse and misuse of antimicrobials in human medicine, agriculture, and livestock production, along with inadequate infection control, poor sanitation, and weak regulatory systems. These interconnected factors create pathways for the rapid spread of resistant bacteria, mobile genetic elements (MGEs), and antibiotic residues.

Livestock farming is a major contributor to the global burden of AR. Antibiotics are used not only to treat and prevent disease but also—especially in some regions—as growth promoters, which accelerates resistance. Global antibiotic consumption in food animals continues to rise, with nearly 100,000 tons used in 2020 alone. Consequently, livestock farms can serve as reservoirs of resistant bacteria and resistance genes, including multidrug-resistant E. coli, Campylobacter, Listeria, and S. aureus. These organisms reach the environment through manure, aerosols, wastewater, and contaminated soil, and can ultimately be transmitted to humans through direct contact or the food chain.

Antibiotic-resistant infections in humans pose an increasing clinical threat, complicating the treatment of pneumonia, bloodstream infections, urinary tract infections, and other common diseases. The WHO highlights critical priority pathogens such as Acinetobacter baumannii, Pseudomonas aeruginosa, and certain Enterobacteriaceae, which are resistant to multiple last-resort drugs. Human misuse—self-medication, poor adherence to prescriptions, and excessive reliance on broad-spectrum antibiotics—plays a central role in accelerating resistance. Socioeconomic factors such as inadequate hygiene, poor infection control, counterfeit medicines, and vaccine hesitancy further compound the crisis.

Environmental compartments—soil, water, sediments, air, and wastewater—act as both natural and human-amplified reservoirs of AR. Resistance genes occur naturally (intrinsic resistome), but human activities have dramatically increased their diversity and abundance. Antibiotic residues from household waste, hospitals, livestock farms, and pharmaceutical manufacturing enter the environment largely undegraded, where they exert continuous selective pressure. Numerous studies have detected ARGs in rivers, sludge, drinking water treatment plants, and even urban air, facilitating their movement back into human and animal populations.

Considering AR crosses human, animal, and environmental boundaries, tackling it requires coordinated, multisectoral strategies. Global organizations—including WHO, FAO, and OIE—have advanced the Global Action Plan on Antimicrobial Resistance, emphasizing improved surveillance, responsible antimicrobial use, cross-border collaboration, and environmental monitoring. Strengthening stewardship programs, enhancing diagnostics, regulating pharmaceutical waste, and promoting biosecurity in agriculture are all essential steps.

About the author

Sadia Khalid is a Scientist-Physician (MBBS, MD) at Tallinn University of Technology. She is driven by a commitment to advance public health and scientific understanding. With research interests spanning molecular medicine, infectious diseases, bacteriology, hepatology, and gastroenterology, she aims to contribute meaningful, evidence-based insights that support health, safety, and community awareness.