Antimicrobials are drugs that are used to treat various infectious diseases caused by micro-organisms like fungi, protozoans, parasites, bacteria and viruses. However, the increase in Antimicrobial Resistance (AMR), which refers to the capability of micro-organisms to survive or proliferate even in the presence of drugs intended to overpower or obliterate them, has challenged the current medical facilities.
In this article, we look into how food is contributing to AMR as well as its effect on global health and methods to combat this issue.
How is AMR linked with our food products?
While antimicrobials are vital for controlling diseases in animals and plants to ensure food security, their non-therapeutic use in farming and aquaculture for growth, feed efficiency, and prevention has raised worries about AMR in food production.
This huge quantity of anti-microbials in food-producing animals, especially in settings where animal production is intensive, adds to the development of AMR. The total amount of anti-microbials used in animals in some countries is up to four times higher compared with the amounts used in humans.
The use of antimicrobials in livestock is substantial, with an estimated 63,200 tons used globally in 2010. It is expected that by 2030, this consumption will increase by 67%, that is approximately 105,600 tons.
In plant agriculture, antimicrobials are rarely used, with fruit production being the main area for preventing infections. Commonly used in crops such as apples and pears, this practice certainly has emerged with general concerns about contributing to resistance on plants and the further complication of controlling AMR.
Excessive antimicrobial use has led to AMR microorganisms in food, causing infections that are hard or even untreatable.
Antimicrobial Residues in Food and their effects
The widespread use of antimicrobials results in the presence of antimicrobial residues in food products that are regularly consumed. Anti-microbial residues are metabolic compounds present in trace amounts in the edible parts of animals following their administration.
When these residues exceed the permissible maximum residue limit in food animals, they may contribute to the development of AMR in both animals and humans. To mitigate these risks, regulatory withdrawal periods are enforced, defining the required interval between the final administration of antimicrobials to animals and their slaughter or the collection of products such as milk or eggs.
These intervals allow sufficient time for the drugs to be metabolized or excreted, ensuring that residue levels in food remain negligible or undetectable at the point of consumption.
Non-compliance with such regulations, however, can expose consumers to unsafe levels of antimicrobial residues, posing toxic risks, digestive disturbances, and heightened vulnerability to infections where the emergence of AMR is more likely.
The CDC estimates that at the very least, in the US, there are 2.8 million people who have contracted infections caused due to antibiotic resistance annually, resulting in over 35,000 deaths and countless additional casualties.
Pathways of AMR development and its spread
AMR can spread through cross-contaminated products that might have come in contact with microbial, chemical or solid pollutants. It can occur from contaminated food, equipment or environment at any stage of food production.
A common belief is that food-borne illnesses mainly stem from eating at restaurants; however, cross-contamination can happen through several different routes, such as:
- Contamination during the cultivation of plants and rearing of animals on farms.
- Exposure to harmful pathogens during food collection or animal processing.
- Contamination during food processing and manufacturing.
- Improper handling that allows bacteria or other contaminants to spread.
- Risks present at grocery stores, farmers' markets, and other points of sale.
- Cross-contamination occurring at home, restaurants, or other food service establishments.
AMR can enter the environment by various pathways, for instance, waste streams released from plants, animals, or humans that were treated with a certain type of antimicrobials, and in the effluent from wastewater treatment plants.
Soils are contaminated from pre-existing anti-microbes that enter the soil using fertilizers, or any other such methods of plant disease control. While water bodies, like the Ganga, Yamuna, and Kaveri, receive pharmaceutical and hospital wastes without proper treatment, resulting in high levels of drug-resistant bacteria. This indicates a dire need for good land and water protection and management practices.
Effects of AMR on Economy and Public health
The economic burden of AMR is that it affects the healthcare system, agricultural sectors and the nation’s productivity. Due to increase in AMR, there is an increase in drug-resistant infections causing longer hospital stays, more treatment costs, and the use of expensive drugs leading to significant healthcare costs.
In agriculture, due to AMR, antimicrobials lose effects on crops, leading to lower yields and higher production costs. Nation wise, AMR can push a nation towards extreme poverty, especially those nations which have limited medical resources and agriculture plays a crucial role in economic stability.
The reliance on anti-microbial has led to the loss of effective first-line treatments, necessitating the use of more expensive, toxic, and prolonged second- and third-line therapies. This not only burdens the medical systems due to prolonged treatments and use of expensive drugs but also affects economic productivity due to longer recovery times and time off work.
Antimicrobial-resistant (AMR) pathogens cause more than a million deaths annually, and their growing presence has increased the risks associated with routine medical treatments like surgeries and chemotherapy. Resistant bacteria such as Enterococcus faecium, Staphylococcus aureus, and Klebsiella pneumoniae, members of the “ESKAPE” group are especially problematic in hospital settings.
Furthermore, AMR also threatens food production, since resistant zoonotic pathogens like Salmonella and Campylobacter can be transmitted from livestock to humans.
Combating AMR
AMR management in the food chain is complicated and requires the implementation of fine practices from the primary production level to the consumption level.
At the production stage, maintaining good hygiene, implementing contamination prevention measures, and ensuring the responsible use of antimicrobial medicines can help lower food safety risks. It does not stop there at the farm gate but requires similar good hygiene practices by all operators down the line, backed up by a risk-based inspection system.
Some countries have banned the use of anti-microbial for growth promotion in animals, but much more stringent regulations are still needed at the global level. Policies to reduce unnecessary antibiotic use in livestock can make a significant difference. For example, Europe has taken the lead in banning many antibiotics that enhance growth, and similar efforts are on the increase across the world.
Systems for monitoring and surveillance of anti-microbial use and the spread of AMR through the human food chain are effective. This includes monitoring programs for presence of residue in veterinary drug, which are implemented in some countries but not in others and generally require further reinforcement.
AMR Laboratory Mapping Tool This helps the countries to review their national capacities with regard to surveillance and laboratory. It is also supporting governments through FAO and the International Atomic Energy Agency to strengthen their capacities in providing training on how to establish and run veterinary drug residue monitoring programs.
Finally, it is important to raise public awareness of food safety and AMR. Consumers also play a role by practicing safe food handling and using antibiotics responsibly.
References
- Lekshmi, Manjusha, Parvathi Ammini, Sanath Kumar, and Manuel F. Varela. "The food production environment and the development of antimicrobial resistance in human pathogens of animal origin." Microorganisms 5, no. 1 (2017): 11.
- Van Boeckel, Thomas P., Charles Brower, Marius Gilbert, Bryan T. Grenfell, Simon A. Levin, Timothy P. Robinson, Aude Teillant, and Ramanan Laxminarayan. "Global trends in antimicrobial use in food animals." Proceedings of the National Academy of Sciences 112, no. 18 (2015): 5649-5654.
- Menkem, Zeuko’O. Elisabeth, Bronhilda Lemalue Ngangom, Stella Shinwin Ateim Tamunjoh, and Fekam Fabrice Boyom. "Antibiotic residues in food animals: Public health concern." Acta Ecologica Sinica 39, no. 5 (2019): 411-415.
- Samtiya, Mrinal, Karl R. Matthews, Tejpal Dhewa, and Anil Kumar Puniya. "Antimicrobial resistance in the food chain: trends, mechanisms, pathways, and possible regulation strategies." Foods 11, no. 19 (2022): 2966.
- Ait Ouakrim, Driss, A. Cassini, M. Cecchini, and D. Plauchoras. "The health and economic burden of antimicrobial resistance." European Journal of Public Health 30, no. Supplement_5 (2020): ckaa165-1201.
- Vikram Chandu, V., Katravath Rajesh Naik, and Mondru Jaji Jerusha Jacob. "Environmental Hygiene-a Key Intervention Strategy in Fighting." (2024).
Frequently Asked Questions (FAQs)
Q1. What is antimicrobial resistance (AMR)?
AMR occurs when microorganisms like bacteria and viruses stop responding to drugs meant to kill them.
Q2. How is AMR linked to food?
The overuse of antimicrobials in livestock and aquaculture contributes to resistant microbes entering the food chain.
Q3. What are antimicrobial residues in food?
They are small traces of drugs left in animal products after treatment with antimicrobials.
Q4. Why is antimicrobial misuse in farming dangerous?
It leads to resistant bacteria that make infections harder or impossible to treat.
Q5. How can consumers reduce AMR risk?
By practicing hygiene, cooking food properly, and avoiding unnecessary antibiotic use.
Q6. How does AMR affect the economy?
It increases healthcare costs, lowers productivity, and affects agricultural yields.
Q7. What are examples of resistant bacteria?
Bacteria like Staphylococcus aureus and Klebsiella pneumoniae are major resistant pathogens.
Q8. How does AMR spread in the environment?
Through waste from humans, animals, and untreated hospital effluents entering soil and water.
Q9. What steps can governments take to control AMR?
They can regulate antimicrobial use, monitor residues, and promote awareness campaigns.
Q10. Is AMR a global concern?
Yes, AMR is a worldwide issue affecting healthcare, agriculture, and the environment.
Authors
Sanvi Nandwana and Poorva Salvi (Fourth Year B. Tech Biotechnology Students)
Dr. Latika Shendre* (Assistant Professor), Microbial Diversity Research Center,
Dr. D. Y. Patil Biotechnology and Bioinformatics Institute, Dr. D. Y. Patil Vidyapeeth,
Tathawade, Pune - 411033, Maharashtra, India.
*Email ID: latika.shendre@dpu.edu.in