Submitted to: Clinical Infectious Diseases
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/17/2002
Publication Date: 6/1/2002
Citation: Mcewen, S.A., Cray, P.J. 2002. Antimicrobial use and resistance in animals. Clinical Infectious Diseases. 34 (Suppl) 3. P. S93 - S106. Interpretive Summary: The increasing numbers of bacteria developing antimicrobial resistance is of growing global concern. Particularly worrisome is the emergence of resistance to multiple antimicrobials which complicates treatment options, and, in some cases, results in an infection that cannot be treated. Use of antimicrobials in both the medical and agricultural areas have contributed to the development of resistance. However, there is much debate as to the degree to which agricultural use of antimicrobials impacts human health. This chapter provides an overview of the use of antimicrobials in food animal production including factors which impact the development of resistance and some alternatives to antimicrobial use and will serve as a reference on the current status of antimicrobial resistance issues in agriculture. It will be useful for scientists, veterinarians, physicians, producers and consumers as they develop research programs and recommend policy.
Technical Abstract: Food animals in the United States are often exposed to antimicrobials to treat and prevent infectious disease or to promote growth. Many of these antimicrobials are identical to or closely resemble drugs used in humans. Precise figures for the quantity of antimicrobials used in animals are not publicly available in the U.S., and estimates vary widely. Antibiotic resistance has emerged in zoonotic enteropathogens (e.g., Salmonella spp., Campylobacter spp.), commensal bacteria (e.g., E. coli, entercocci), and bacterial pathogens of animals (e.g., Pasteurella, Actinobacillus spp.), but the prevalence of resistance varies. It is clear that antibiotic resistance emerges from the extensive use of antibiotics in animals and the subsequent transfer of resistance genes and bacteria among animals and animal products and the environment. To slow the development of resistance, some countries have restricted antimicrobial use in feed, and some groups advocate similar measures in the US. Alternatives to growth-promoting and prophylactic uses of antimicrobials in agriculture include improved management practices, wider use of vaccines, and introduction of probiotics. Monitoring programs, prudent use guidelines, and educational campaigns provide approaches for minimizing the further development of antimicrobial resistance.