The judicious use of antimicrobials in food animals keeps them healthy, and healthy animals mean healthy food products for humans.Judicious use means that veterinarians and producers use good judgment to decide when and how an antimicrobial is to be used to maximize public and animal health benefits while minimizing risks.1,2
It is crucial that safe and effective antimicrobials remain available for use in veterinary medicine to ensure the health and welfare of animals, and consequently the health of humans.The Preservation of Antibiotics for Medical Treatment Act (PAMTA) is a bill that seeks to eliminate many of the beneficial uses of antimicrobials, but the rationale for its enactment is not supported by scientific data.
Multiple governmental organizations including the USDA and FDA, as well as veterinarians in practice, strive to ensure that America's food supply is safe.Animals, and thus our food supply, are kept healthy with judicious use of antimicrobials, vaccinations, parasiticides, good nutrition and good management practices.
The U.S. Food and Drug Administration has approved the use of antimicrobials for four purposes:growth promotion/feed efficiency, prevention of disease, control of disease, and treatment of disease.1
Several types of antimicrobials are used for production or enhancing growth, to alter the animal's gut microflora, and to decrease the level of pathologic bacteria present. These are often referred to as growth promoters. Antimicrobials should not be confused with growth hormones or performance-enhancing drugs, such as steroids.
Animal illness can be predictable and occur with some regularity even in well-managed conditions,thereby requiring interventions (including antimicrobial therapy) as a preventive course of action. Veterinarians have the education, skills, and expertise to be able to predict the regularities in which these disease conditions occur and be able to prevent them when the tools (including antimicrobials) are available.
There are only a limited number of antimicrobials for human and animal use. Therefore, veterinarians are just as concerned about resistance as human health professionals.
Although over-the-counter (OTC) antimicrobials are available, they are well regulated.In fact, there are greater restrictions on the use of antimicrobials in animals than there are for use in humans.
All uses of drugs in food-producing animals is subject to federal regulation
Veterinary Feed Directive (VFD) is a category of drugs intended for use only in or on animal feed, must be used exactly as prescribed, and require the direct supervision of the veterinarian as well as a valid veterinarian-client-patient-relationship.The extralabel use of a VFD drug is not permitted under any circumstances because the drug goes into animal feed.
There are 3 theorized mechanisms for the spread of resistance from food animals to humans predicated on the assumption that antimicrobial use in food animals affects human resistance through the consumption of animal products:
Antimicrobial resistance is most commonly seen when a pathogen is transmitted from human to human. Several cases have been reported that show direct transmission of a resistant organism from animal to human; however, Based on peer-reviewed risk assessment to date, the risk to people of becoming infected with resistant organisms by consuming animal products (meat, milk, eggs) is extremely low.14,15,16,17,18,19,20,21,22 The indirect foodborne route of transmission has never been demonstrated.
Based on available science, the likelihood that human consumption of animal products (meat, eggs, milk) will lead to an infection with resistant organisms is negligible.1
Each drug must be considered individually because of relative risks, benefits, and differing abilities to select for resistance. The benefits of some uses for animal health and welfare may outweigh the risks.
More research and risk-based analyses are needed to determine the risks associated with antimicrobial use and to formulate a strategy to maximize the benefits while minimizing the risksbefore we institute stringent legislation that could negatively affect not only the health of animals, but also human health.
The AVMA would like to thank Dr. Scott Hurd, Professor, Iowa State University College of Veterinary Medicine and member of AVMA Council on Biologic and Therapeutic Agents (COBTA) representing epidemiology; and Jessica Green, University of Illinois College of Veterinary Medicine Class of 2012; for their contributions to this document.
This information has been prepared as a service by the American Veterinary Medical Association. Redistribution is acceptable, but the document's original content and format must be maintained, and its source must be prominently identified. Please e-mail Dr. Kimberly May or call (800.248.2862, ext 6667) with questions or comments.