Veterinary antimicrobial stewardship in North America.

Major changes are occurring in veterinary antimicrobial stewardship (AMS) in food animals in Canada and the USA. Advances have been ending the use of medically important antimicrobials (MIAs) as growth promoters and bringing all MIAs for food animals under veterinary prescription in Canada (2018) or MIAs in feed or water under veterinary prescription (2017) in the USA. The USA proposes bringing all MIAs for food and companion animals under veterinary oversight, to reduce the duration of preventive use for food animals and to develop a strategy for companion animals. Both countries are taking a 'One Health' approach as part of their national strategies on addressing AMS. Federal state or province jurisdictional issues have impeded development and implementation of regulation-based stewardship approaches. Veterinary regulatory bodies in some of the larger states and provinces are active in AMS. Both the American and Canadian veterinary medical associations are independently heavily engaged in promoting AMS, as are, variably, the different veterinary 'specialty' groups. Regulatory changes and market demand are markedly reducing the use of antimicrobials in food animals. The promotion of veterinary AMS is happening at an increasing pace.