WHO Draft Recommendations on prudent use of antimicrobials in food-producing animals

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Purpose

To minimise the potential negative public health impact of the use of antimicrobial agents in food-producing animals whilst at the same time providing for their safe and effective use in veterinary medicine.

Approval and licensing

1. National governments should adopt a proactive approach to reduce the need of antimicrobials in animals and to ensure their prudent use, in accordance with similar strategies in humans.

2. Relevant authorities should develop strategies that reduce the potential risk to public health from resistant zoonotic bacteria, prolong the efficacy of veterinary antimicrobial products, and ensure the maintenance of animal health.

Responsibilities of licensing authorities

3. Decisions concerning licensing of veterinary antimicrobial substances should include safety considerations regarding the human health impact of resistance developing in food animals associated with the use of antimicrobials.

4. No antimicrobial should be administered to animals unless it has been evaluated and authorised for such use by relevant authorities. Exceptionally, where no antimicrobial drugs for use in a species or specific indication is available or, an authorised product is demonstrated as no longer being effective, then a product authorised for another indication or other species may be used under direct supervision of a veterinarian, and provided an extended withdrawal period is applied.

5. The authorisation of veterinary antimicrobial products should take account of data on antimicrobial resistance among relevant bacterial strains and should ensure that recommended dosages are optimal for therapy, taking into consideration pharmacokinetics, clinical endpoints and residues, and if available other data which can be considered, in order to minimise the development of resistance.

6. A risk-based evaluation of the potential human health effects of uses of antimicrobial drugs in food-producing animals should be conducted. Characterisation of the risk should include consideration of the importance of the drug or members of the same class to human medicine, the potential exposure to humans from resistant pathogens from food animals, as well as other appropriate scientific factors.

7. Decisions regarding licensing of antimicrobials for use in food animals should be based on scientific evidence, which should, unless otherwise justified, include the evaluation of pre-approval studies to model the potential rate and extent of resistance in relevant human bacteria associated with the proposed use in food animals.

8. For currently approved products application of a similar risk based evaluation should be considered. Prioritisation of evaluation should be focused on those products considered most important in human medicine.

Post-approval

9. Post-approval surveillance of antimicrobial resistance is indispensable. Identification of the appropriate bacteria, methods of collection and relevant antimicrobials to be included in such post-approval surveillance programmes should be guided by a risk-based priority list and be based on the direction of the relevant authority. The methods and data should be made publicly available. Such surveillance may be carried out with the participation of the veterinary pharmaceutical industry.

10. Antimicrobials belonging to classes considered essential for treatment of (serious life threatening) diseases in humans (when alternatives are limited) should be closely monitored in surveillance programmes to ensure that such use does not pose a risk to public health.

11. Epidemiological and/or experimental investigations to identify risk factors may be needed if resistance increases above acceptable levels, and mitigation strategies, such as labelling changes, changes in dosing and duration of use, should then be implemented. If and when the ongoing assessment of the risk demonstrate it to be unacceptable, withdrawal of an antimicrobial for veterinary use from the market, should be considered.

12. Post-approval surveillance should be able to detect emerging problems of antimicrobial resistance in time to allow effective corrective strategies to be implemented that can be part of an efficient post-licensing review.

Quality

13. Antimicrobial products, including generic products, should be manufactured in accordance with the current good manufacturing practices (GMP) and following the specifications laid out in the licensing application by the relevant authorities. Relevant authorities that lack the necessary resources to evaluate product applications should provide for alternative mechanisms, such as third party certification, to ensure safe, effective and quality products are licensed for use.

Distribution and sale

14. Enforcement policies should be designed to ensure compliance with laws and regulations pertaining to the authorisation, distribution and sale and the use of antimicrobials. They should aim at preventing the illicit manufacture, importation, sale and control the distribution and use of antimicrobials.

15. Special attention should be paid to the distribution and sale of counterfeit, subpotent and misbrand veterinary antimicrobials. Enforcement action should be taken to stop such distribution and sale by relevant authorities, in co-ordination with the exporting country, if appropriate.

16. Relevant authorities should ensure that all antimicrobials for disease control in animals are classified as prescription only medicine unless, under exceptional circumstances when veterinary advice is not available alternative means of disease control must be facilitated.

17. Relevant authorities should ensure that all antimicrobials for animal use should be supplied only through authorised outlets (such as pharmacies on veterinary prescription, veterinary practices, and, in the case of materials used in animal feeding stuffs, feed mills).

18. Sales of medicines may constitute a significant portion of the income of practising veterinarians in some countries. If evidence exists that sale of medicines negatively impacts prescribing practices, appropriate countermeasures should be taken.

Advertising and promotion (marketing)

19. Pharmaceutical companies should pay attention to the link between marketing practices, such as inappropriate advertisement and economical incentives, and the potential for overuse and misuse of antimicrobials. There should be no promotion of prescription-only antimicrobial products to non-professionals.

Surveillance of antimicrobial consumption

20. A relevant recognised authority should take steps to establish systems to determine the amounts of antimicrobials given to food animals.

21. Information on the amounts of antimicrobials given to food animals should be made publicly available at regular intervals and should, ideally, be structured to permit further epidemiological analyses.

22. Veterinarians should continuously evaluate their prescribing practices. This would, amongst others, be based on information on average amounts and types of antimicrobials. These data could be made available through national or regional surveillance systems or record keeping in veterinary clinics.

Record keeping at the farm

23. For each group of animals, a health record should be kept including data on antimicrobial use, and results of previous antimicrobial susceptibility tests to support choice of antimicrobial in empirical therapy in acute disease outbreaks.

Surveillance of antimicrobial resistance

24. Programmes to monitor antimicrobial resistance in animal pathogens, zoonotic agents (for example salmonella and campylobacter), and bacteria known to be indicators of antimicrobial resistance (for example E. coli and E. faecium) should be implemented on bacteria from animals, food of animal origin and humans. Veterinarians, medical doctors and authorities should be kept regularly informed about the surveillance results and trends.

25. Data generated from the surveillance of antimicrobial resistance should play a key role in the development of national policies for the containment of antimicrobial resistance. These data are also essential in the pre- and post-licensing process and in the development of treatment guidelines for veterinary use.

The use of antimicrobials in farm animals

The veterinarians responsibility
26. The veterinarian should perform regular health audits at farms under his/her care. Animal health programmes should focus on preventive strategies, such as good farming practice (GFP) or other quality assurance programmes.

27. A veterinarian should only prescribe antimicrobials for animals under his/her direct care. A veterinarian is expected to have examined clinically affected animals, or to be familiar with production practices on the farm and to have developed a written treatment protocol, prior to prescribing medication.

28. Antimicrobials should only be applied when indicated, using antibiotics directed against the causative agent/s, given in optimal dosage, dosage intervals and length of treatment with steps taken to ensure maximum concordance with the treatment regimen, and only when the benefit of the treatment outweighs the inherent risks.

The producers responsibility
29. It is the responsibility of the producers to ensure that production systems promote animal health and welfare. Antimicrobial usage, if necessary, should always be a part of, not a replacement for, an integrated animal health programme. Such a programme is likely to involve hygiene and disinfection procedures, bio-security measures, management alterations, changes in stocking rate, vaccination, etc.

30. The farmer and the veterinarian should cooperate to achieve joint responsibility for health of the animals in their care. The veterinarian and the producer should agree on written protocols and/or policies on treatment programmes and veterinary involvement in ongoing disease conditions at farm level, and regularly updated.

Prudent use guidelines/treatment formularies
31. The strategic aim of policies expressed in guidelines should be to provide advice on:

  1. optimal therapeutic effect and/or protection of animals at risk;
  2. the control of antimicrobial resistance in animal and zoonotic bacteria;
  3. practical, affordable treatment that minimises the risk of potentially harmful levels of residues in animal products intended for human consumption.

32. Guidelines on the prudent use of antimicrobials in animals should be readily accessible, written with multidisciplinary prescriber involvement, subject to peer review and compatible with existing regulations, and should be evaluated and revised at regular intervals.

33. Guidelines may include a list of recommended antimicrobials for more than 90% of the conditions commonly presenting in clinical practice and provide a rational treatment choice based on scientific data, the results of disease and resistance surveillance and practical experience. Guidance should include data on appropriate dosage, range and duration of application, and residue problems (withdrawal times). If several antimicrobials can be used, guidelines should make recommendations on different antimicrobials to be used, based on antimicrobial susceptibility, disease patterns in animals and human health concerns.

Prophylactic treatment
34. Use of antimicrobials for prevention of disease can only be justified where it can be shown that a particular disease is present on the premises or is likely to occur. The prophylactic use of antimicrobials is never a substitute for good animal health management.

35. Prophylactic use of antimicrobials in control programmes should be regularly assessed as to effectiveness and whether use can be reduced or stopped.

Antimicrobial growth promoters

36. A risk-based evaluation of all antimicrobial growth promoters should be conducted. Characterisation of the risk may include consideration of the present and potential future importance of the drug to human medicine, its selection of resistance, the potential exposure to humans from resistant bacteria from food animals, as well as other appropriate scientific factors.

37. In the absence of such risk evaluations antimicrobial growth promoters that belong to classes of antimicrobial agents used (or proposed to be used) in humans and animals should be phased out, preferably by voluntary agreement between the authorities and the food animal producers, but by legislation if necessary.

Education and training

38. Veterinary undergraduate and postgraduate training should be evaluated to ensure that preventive medicine and antimicrobial resistance are given a suitably high profile.

39. Ongoing education strategies must be developed by entities such as professional associations, relevant authorities, FAO and/or educational institutions to provide relevant professional bodies and stakeholders with appropriately targeted information about infections, the role and benefits of prudent antimicrobial use and the risks of inappropriate use. The veterinary pharmaceutical industry should be encouraged to support this effort.

40. Continuous evaluation of the effectiveness of the prudent use educational strategies should be conducted.

41. Education strategies must be developed and implemented to provide relevant information on antimicrobial resistance for producers and stakeholders emphasising the importance and benefits of prudent use principles. Emphasis must also be given to stressing the importance of optimising animal health through good management practices.

Research

42. Governments, research foundations and industry should give high priority to support research in the following areas: