We examined the international regulatory landscape related to the use of antimicrobials in food animal production. We sought to establish which jurisdictions have national requirements that veterinarians oversee antimicrobial use in food animals, and which jurisdictions have restricted the use of antimicrobials in food animals for growth promotion and, if information was available, disease prevention and control. We were able to ascertain answers to most of these questions for 17 political jurisdictions, and found that there are varying levels of antimicrobial controls in these settings, with restrictions on AGPs being the most common.
Six jurisdictions have stringent restrictions on antimicrobial use in food animal production. It is illegal to use antimicrobials for growth promotion in those settings and each requires a veterinary prescription to use antimicrobials in food animals. While the EU requires veterinary prescriptions for antimicrobial use, it exempts some of its 27 member states. Separately, five jurisdictions have fewer restrictions on antimicrobial use, with either full or partial AGP bans or veterinary prescription requirements. Five other jurisdictions do not have any restrictions on the use of antimicrobials for growth promotion at the national level or requirements to obtain veterinary prescriptions for their use (Table 2).
While a ban on growth promotion has been central to debates over antimicrobial use in the U.S., some jurisdictions’ policies have included more dynamic approaches as well. Denmark’s yellow card initiative, for example, combines robust surveillance of antimicrobial use with requirements to implement alternative measures when reported use is deemed excessive . Proposed legislation in Germany would initiate a similar program . These models recognize the importance of antimicrobials to animal health and the need for clinical judgments by qualified veterinarians, as well as the public health risks posed by misuse of these drugs. Denmark has also taken steps to limit financial conflicts of interest that may incentivize veterinarians to prescribe antibiotics excessively . Neither approach has featured prominently in U.S. policy debates. A barrier to their adoption in the U.S. is the absence of a surveillance system for antimicrobial use in food animals.
Data on impacts of antimicrobial use restrictions on food animal production in these jurisdictions continue to be limited. Most information comes from the experiences of Denmark and Sweden, which were early adopters of antimicrobial controls. Their respective producers have suggested that stringent AGP controls can be implemented with minimal economic consequences for industry. Producers in Denmark and Sweden did not report increased mortality or encounter other obstacles in poultry, swine, beef and dairy products other than those described in this work. Producers did report elevated mortality and increased production time although those increases have been reduced over time as management practices have adapted [27, 40, 41].
Differences among jurisdictions with respect to food animal production policies have threatened U.S. access to export markets for these products. The EU has long prohibited the importation of U.S. beef produced with exogenous hormones, citing drug residues as a concern . The bloc currently permits the importation of a limited quantity of beef derived from cattle certified by the U.S. government as “non-hormone treated” . While the economic impact of this restriction is difficult to estimate, initial losses were projected at approximately $100 million per year . Since 1997, the EU has also prohibited the importation of poultry processed with antimicrobial rinses, arguing that such treatments are less effective at reducing microbiological contamination than improved sanitation in production and processing . Before 1997, U.S. poultry exports to the 15 countries that then comprised the EU were valued at $52 million; in 2011, poultry exports to those countries were valued at $13 million .
Beyond the EU, Taiwan had banned beef and pork products with detectable residues of ractopamine, a growth promotion and leanness drug used in the U.S. . This ban was subsequently revised to permit ractopamine residues in beef up to 10 ppb while maintaining a zero-tolerance for ractopamine in pork . U.S. access to the Russian market has been hampered in recent years by multiple issues, including antimicrobial drug residues and antimicrobial rinses . The U.S. has long maintained that restrictions adopted by the EU, Taiwan, and Russia are not grounded in scientific evidence of human health risk, and that they instead represent economic protectionism [25, 26, 47].
Although international trade policies often hinge on myriad factors—for example, the most recent restrictions adopted by Russia appear to have been retaliation against criticism of the country’s human rights record by the U.S. Congress —previous restrictions may still be instructive in the context of AMR. As concern over the contribution of food animal production to AMR in human pathogens increases, efforts to limit U.S. food animal exports further may emerge. In 2011, the EU adopted a resolution that called on its member states to “work towards an international ban on antimicrobials as growth promoters in animal feed, and to bring this matter up in its bilateral negotiations with third countries such as the United States” . This suggests that, as with hormones and antimicrobial rinses, the EU may view antimicrobial use in food animals as a trade issue. Potential trade sanctions against the U.S. would likely lead to long-term consequences for the U.S. export market, stemming both from declining production capacities during sanctions as well as geographic dislocation of the market.
The World Trade Organization, which adjudicates trade disputes between its member states, relies principally on the opinions of the Codex Alimentarius Commission in cases involving food safety . In 2005, the Commission published its “Code of Practice to Minimize and Contain Antimicrobial Resistance” . The Code states, “The responsible use of veterinary antimicrobial drugs in food-producing animals…does not include the use for growth promotion of veterinary antimicrobial drugs that belong to or are able to cause cross resistance to classes of antimicrobial agents used (or submitted for approval) in humans in the absence of a risk analysis.” The Code also calls for veterinary oversight of antimicrobial use and emphasizes alternatives to antimicrobial use for disease prevention. In many cases, the current use of antimicrobials in U.S. food animal production appears to be inconsistent with these principles [16, 51]. Although the FDA has recommended that pharmaceutical companies voluntarily withdraw approvals to market antimicrobials for growth promotion and require veterinary oversight of their use , the compliance of companies with these recommendations is uncertain. The agency has not moved to restrict antimicrobial use for disease prevention .