Antibiotics in Agriculture: Need for One Health Approach

Jackie Linden
06 February 2013, at 12:00am

US - For progress to be made in resolving the issues surrounding antibiotic use in livestock production, leaders in animal, human and environmental health must find common ground. That is among the conclusions in a White Paper from the 2012 Antibiotics Conference.

The conference, 'A One Health Approach to Antimicrobial Use & Resistance: A Dialogue for a Common Purpose' was held in Columbus, Ohio in November 2012, organised by the US the National Institute for Animal Agriculture (NIAA).

Antibiotics improve human, animal and plant health, and increase life expectancy, according to the Executive Summary of the report. While a majority of individuals acknowledge the positive role antibiotics play in the health of humans, animals and plants, the topic of antimicrobial resistance - when antibiotics can no longer cure bacterial infections - is frequently misunderstood, misappropriated and polarizing.

Antimicrobial resistance occurs via three mechanisms, each requiring only minor changes in biochemistry: 1) Bacteria may possess enzymes that degrade antibiotics; 2) Bacteria may replace or alter the method through which the antibiotic enters the cell; and 3) Bacteria may alter the cellular target site of the antibiotic. A historical look at antimicrobial resistance shows it is not a new phenomenon but existed before widespread use in human and animal medicine.

Antimicrobial resistance is not a black-and-white issue. Antimicrobial resistance is complex and is more than science and evidence. It is about politics, behavior, economics and conflicting opinions. And it is not merely a consequence of use; it is a consequence of use and misuse, with each communityanimal health, human health and environmental healthresponsible for antibiotic stewardship.

A significant amount of finger pointing regarding antimicrobial use and misuse has been aimed at animal agriculture. Since 2010, bloggers and media use 80 per cent as a de facto number for antibiotic usage in animals. While animal agriculture does use antibiotics in the care and treatment of food animals, the statement that 80 per cent of antibiotics in the United States is used in healthy animals is not accurate as it was deduced from comparing two sets of data that are not comparable. The 80 per cent figure demonstrates a different way antibiotic use is counted, with the estimates for animal use collectively were derived by an entirely different methodology than the estimate presented for human use. In addition, 35 per cent of the use the calculation attributed to animals are compounds not used in human medicine, thus minimizing potential interference with effectiveness of antibiotics used to treat human disease.

Use of antibiotics in food animal production is highly regulated by the US Food and Drug Administration Center for Veterinary Medicine (FDA CVM). In addition, regulatory oversight provides assurance in the development of safe products. Education and training (e.g. livestock species Quality Assurance Programs encourages producers to have a strong relationship with their veterinarians and provides guidance on the responsible use of antibiotics. Government surveillance and testing ensures that no harmful residues, as established by the FDA, enter the food supply.

On the human side, the discovery of antibiotics in the 1930s has allowed physicians to shift their patient care approach from diagnoses without means to intervene to a treatment-focused approach that saves lives. To date, physicians have significant freedom to use antibiotics, and antibiotics are being used off-label, which can lead to inappropriate usages. Given the societal value of antimicrobials, the diminishing effectiveness due to antimicrobial resistance, and the fact that 200 million to 300 million antibiotics are prescribed annually, the Infectious Diseases Society of America (IDSA) - which represents physicians, scientists and other health care professionals who specialize in infectious diseases - is taking steps to address antibiotic misuse through an antimicrobial stewardship program. The Centers for Disease Control has implemented a 'Get Smart for Healthcare' program that focuses on improving antibiotic use in inpatient healthcare facilities, starting with hospitals, then expanding to long-term care facilities.

Human medicine's focus on stewardship and other important areas is an action taken to lessen antibiotic misuse as uncovered in these studies: 1) Studies indicate that nearly 50 per cent of antimicrobial use in hospitals is unnecessary or inappropriate;14 2) In another study, antibiotics were prescribed in 68 percent of acute respiratory tract visits and of those, 80 percent were unnecessary according to Centers for Disease Control guidelines;15 3) In other surveys, 80% of physicians in the United States admitted to writing outpatient prescriptions for antibiotics when they thought it unnecessary because their patients adamantly demanded antibiotics.

Antimicrobial use is not limited to animal agriculture and human medicine. Antimicrobials are also used in plant agriculture. Streptomycin has been utilized in plant disease management since the early 1950s. Other antibiotics used in plant agriculture include oxytetracycline and kasugamuycin. While estimates from a US Geological Survey and from the National Agricultural Statistics Service show that plant use of antibiotics is less than 0.5 per cent of 22.6 million kilograms of annual US production of antibiotics, antibiotic use in plant agriculture contributes to the antimicrobial resistance equation.

The scale and complexity of animal and human medical challenges embedded in a changing environment demand that those within the animal, human and environmental health fields move beyond the confines of their own disciplines and explore new organizational models for team science.

The time has come for those in animal health, human health and environmental health to disentangle the facts vs. perceived facts regarding antimicrobial resistance, separate people from problems and focus on creating mutually satisfying outcomes and interests. Finding common ground and reaching agreement is essential.

With animal, human and environmental health inextricably linked, one logical answer is to take a One Health approach. This approach would call for all to think in a much larger dimension and work toward improving and defending the health and well-being of all species by enhancing cooperation and collaboration between physicians, veterinarians, other scientific health and environmental professionals, and by promoting strengths in leadership and management to achieve these goals.

For strides to be made, leaders in animal, human and environmental health must find common ground. This is not about compromise where everyone gives up something. Its about suspending reactions, emotions and distrust; putting positions aside and interests first; and reaching consensus on the issue of antibiotic use and resistance. Reaching agreement must begin with the end in mind: improving health.

The symposium 'One Health Approach to Antimicrobial Use & Resistance: A Dialogue for a Common Purpose' was developed by the National Institute for Animal Agriculture (NIAA) and conducted on 13 to 15 November 2012 in Columbus, Ohio. The symposium was a continuation of discussions and sharing of information that began a year prior at NIAA's 'Antibiotic Use in Food Animals: A Dialogue for a Common Purpose' symposium on 26 to 27 October 2011 in Chicago, Illinois.

Further Reading

You can view the full report by clicking here.