What is it?
Health Canada classifies antimicrobials based on their importance in human medicine as follows [1]:
- Category I: Very High Importance
- These antimicrobial drugs have no or limited alternatives available and are essential for the treatment of serious infections.
- Category II: High Importance
- These antimicrobial drugs often gave an alternative available but are still used to treat serious infections.
- Category III: Medium Importance
- These antimicrobial drugs are not typically used for serious infections in humans. Alternative options are generally available.
- Category IV: Low Importance
- These antimicrobial drugs are not used in human medicine and are the most commonly used antimicrobial drugs used in beef cattle [1], [2]. They include flavophospholipols and ionophores.
The World Health Organization (WHO) also has a classification system, which includes antimicrobials classified as important, highly important, and critically important [3], [4]. The WHO has also set forth recommendations and best practice statements in their guidelines, which they encourage countries to adopt within their own legislation and regulations.
Some drugs are more medically important than others when treating infections, and therefore will be ranked higher. Low-importance antimicrobials are not classified as medically important, and the majority of antimicrobials used in Canadian beef production fall under this category [2]. Medically important antimicrobials may also be used for cattle; however, they are used less frequently and at the discretion of a veterinarian.
How Does it Prevent AMR?
By limiting the use of more important antimicrobials, their efficacy can be prolonged, and we can reduce the risk of resistance developing to these drugs. The use of medically important antimicrobials for production purposes, such as for growth promotion, has been banned in Canada since 2018 [5]. Additionally, all growth promotion claims must be removed, and responsible use statements added on all labels for medically important antimicrobials
In terms of antimicrobial stewardship, by choosing the right drug, at the right time, with the right dose, and right duration, we can use antimicrobials more responsibly.
This is a clinical decision support application. It has both human and animal health versions of the app available.
Further Reading
Research Gaps
Product/Service Gaps
References
[1] Health Canada, ‘Categorization of Antimicrobial Drugs Based on Importance in Human Medicine’, Sep. 21, 2009. https://www.canada.ca/en/health-canada/services/drugs-health-products/veterinary-drugs/antimicrobial-resistance/categorization-antimicrobial-drugs-based-importance-human-medicine.html (accessed Aug. 23, 2022).
[2] Beef Cattle Research Council, ‘Antibiotic Resistance’, Beef Research, Jul. 25, 2022. https://www.beefresearch.ca/topics/antibiotic-resistance/ (accessed Aug. 23, 2022).
[3] World Health Organization, ‘WHO Advisory Group on Integrated Surveillance of Antimicrobial Resistance (AGISAR)’, World Health Organization, Geneva, 2018. Accessed: Aug. 23, 2022. [Online]. Available: https://apps.who.int/iris/handle/10665/272714
[4] P. C. Collignon et al., ‘World Health Organization Ranking of Antimicrobials According to Their Importance in Human Medicine: A Critical Step for Developing Risk Management Strategies to Control Antimicrobial Resistance From Food Animal Production’, Clin. Infect. Dis., vol. 63, no. 8, pp. 1087–1093, Oct. 2016, doi: 10.1093/cid/ciw475.
[5] Government of Canada, ‘Responsible use of Medically Important Antimicrobials in Animals’, Oct. 02, 2017. https://www.canada.ca/en/public-health/services/antibiotic-antimicrobial-resistance/animals/actions/responsible-use-antimicrobials.html (accessed Aug. 23, 2022).
