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Antimicrobial Resistance

Antimicrobial Resistance

An explanation of antimicrobial resistance and answers to questions.

  • What is Antimicrobial Resistance (AMR)?

    Antimicrobial resistance (AMR) is where the medicines (e.g., antibiotics) used to treat diseases caused by specific micro-organisms (e.g., bacteria) are no longer effective.

  • Why are antimicrobials so important?

    Antimicrobials were first discovered nearly 100 years ago. In 1929, Alexander Fleming identified the first antibiotic, penicillin. In his 1945 Nobel Prize lecture, Fleming reminded the world of the need to use antibiotics cautiously to ensure their continued effectiveness.

    Many advances in modern medicine would have been impossible without antimicrobials. They are essential to reduce mortality rates from infectious diseases and to provide protection against infectious complications from surgery, organ transplantation, neonatal care and cancer treatment. In animal health, antimicrobials are used for the treatment of disease in farming and companion animals. Their use is important for the protection of animal welfare, and in the treatment of disease in animals, including zoonotic diseases (i.e., diseases that may be transmitted between animals and humans).

  • What is the problem?

    The problem at present is that the sheer volume of antimicrobials being used globally in humans, animals and in other situations is leading to significant increases in the rate of development of resistance with the result that common infections are becoming more difficult to treat and micro-organisms that are resistant to many antimicrobials (often referred to as ‘superbugs’) are emerging.

  • How do micro-organisms become resistant to antimicrobials?

    The development of resistant strains is a natural phenomenon, which is very complex and multi-factorial. Excessive or inappropriate use of antibiotics or other antimicrobials increases the development and spread of resistance. Poor infection control practices, and in particular poor disease prevention strategies, further encourage the spread of AMR.

  • Are there new antimicrobials being developed to replace the current antimicrobials when they become no longer effective?

    It is unlikely there will be any new classes of antimicrobials available for many years. The last time a new class of antibiotic came to market was 1987. Pharmaceutical companies are developing less antimicrobials now compared to the last century (18 antibiotics in 1990, down to only six in 2016). Antimicrobials are a scarce commodity and they need to be used prudently to sustain and extend their use for years to come.

  • What will happen if the incidence of AMR continues to rise?

    If the incidence of AMR continues to rise, suitable treatment options for both human and animal diseases will not be available in the near future as the number of previously effective antimicrobials which are no longer effective to treat disease increase. AMR is a serious potential threat to both human and animal health globally. AMR carries a heavy economic burden due to higher costs of treatments and reduced productivity caused by sickness. In the EU, it is estimated that AMR is responsible for 25,000 deaths per year and costs 1.5 Billion Euro per year in healthcare costs and productivity losses.

  • What action is being taken to tackle AMR on a global scale?

    The World Health Organization (WHO), the World Organisation for Animal Health (OIE) and the Food and Agriculture Organization of the United Nations (FAO) recognise that AMR requires a collective and practical response and are committed to jointly fighting antimicrobial resistance. In 2015, the World Health Assembly endorsed a global action plan to tackle antimicrobial resistance, including antibiotic resistance, the most urgent drug resistance trend. The goal of the global action plan is to ensure, for as long as possible, continuity of successful treatment and prevention of infectious diseases with effective and safe medicines that are quality-assured, used in a responsible way, and accessible to all who need them. To achieve this goal, the global action plan sets out five strategic objectives:

    1. To improve awareness and understanding of antimicrobial resistance
    2. To strengthen knowledge through surveillance and research
    3. To reduce the incidence of infection
    4. To optimize the use of antimicrobial agents
    5. Develop the economic case for sustainable investment that takes account of the needs of all countries, and increase investment in new medicines, diagnostic tools, vaccines and other interventions

    The OIE, the international reference organization for standards related to animal health and zoonotic diseases, has been working to fight antimicrobial resistance through standard setting for and capacity building of Veterinary Services, livestock producers, and other stakeholders of the animal production industry. It is recognised that antimicrobials agents are essential tools for protecting animal health and welfare. They also contribute to satisfying the increasing world demand for safe and humanely produced food of animal origin.

    The OIE Strategy on Antimicrobial Resistance and the Prudent Use of Antimicrobials (November 2016) is aligned with the WHO Global Action Plan and recognizes the importance of a “One Health” approach – involving human and animal health, agricultural and environmental needs. The OIE AMR Strategy details four objectives to support Member Countries in averting the threat of AMR. The objectives are:

    1. Improve awareness and understanding
    2. Strengthen knowledge through surveillance and research
    3. Support good governance and capacity building
    4. Encourage implementation of international standards
  • What is the European Union doing in response to AMR?

    In June 2017, the European Commission built on its 2011 action plan when it adopted the EU One Health Action Plan against AMR. Its overarching goal is to preserve the possibility of effective treatment of infections in humans and animals. It provides a framework for continued, more extensive action to reduce the emergence and spread of AMR and to increase the development and availability of new effective antimicrobials inside and outside the EU. The key objectives of the new plan are built on three pillars:

    1. Making the EU a best practice region
    2. Boosting research, development and innovation
    3. Shaping the global agenda
  • How can a ‘One Health’ approach stop AMR?

    ‘One Health’ is a worldwide concept which promotes interdisciplinary collaborations and sharing of information in relation to all aspects of health care for humans, animals and the environment. Tackling the threat of AMR globally requires a ‘One Health’ approach because of the zoonotic nature of some disease causing pathogens e.g. SalmonellaCampylobacter, Shiga-toxin producing E. coli (STEC). AMR micro-organisms arising either in humans, animals or the environment may spread from one to the other, and from one country to another. Use of antimicrobials in food animals can create an important source of antimicrobial resistant micro-organisms that can spread to humans through the food supply. Improved management of the use of antimicrobials in food animals, particularly reducing those critically important for human medicine, is an important step towards preserving the benefits of antimicrobials for people.

    Since 2005, WHO has produced a regularly updated list of all Critically Important Antimicrobials (CIAs) currently used for human medicine (mostly also used in veterinary medicine), grouped into three categories (Critically Important, Highly Important, Important) based on their importance to human medicine. The list is intended to assist in managing antimicrobial resistance, ensuring that all antimicrobials, especially CIAs, are used prudently both in human and veterinary medicine. Use of this list will help preserve the efficacy of these medicines, which are in some cases ‘last resort’ treatments in human medicine.

    In 2007, the OIE unanimously adopted the list of antimicrobial agents that are critically important for veterinary medicine (2021 edition). The list is regularly updated and addresses all antimicrobials used in food-producing animals, divided into critically important, highly important and important antimicrobials. In 2007, FAO/OIE/WHO experts met to consider the WHO and OIE lists of critically important antimicrobials and to address the overlap of the two lists. The potential hazards to public health resulting from this overlap and the combinations of pathogen, antimicrobial and animal species of most concern were considered. The meeting concluded that the lists of critically important antimicrobials should be revised on a regular basis in a collaborative and coordinated approach by FAO, OIE and WHO.

    In 2017, WHO published guidelines on use of medically important antimicrobials in food-producing animals, recommending that farmers and the food industry stop using antibiotics routinely to promote growth and prevent disease in healthy animals. These guidelines aim to help preserve the effectiveness of antibiotics that are important for human medicine by reducing their use in animals.

  • What is the national response to tackle AMR?

    At the national level, Ireland has published its first ‘One Health’ National Action Plan on Antimicrobial Resistance 2017-2020 (iNAP) which is aimed at tackling the serious and increasing threat posed by AMR. iNAP was developed by the Department of Health and the Department of Agriculture, Food and the Marine with guidance from the National Interdepartmental AMR Consultative Committee (of which the Food Safety Authority of Ireland (FSAI) is a member), and in consultation with principal stakeholders across the human and animal health sectors. This plan seeks to build on actions already being taken by each sector separately, in pursuit of the overall goal of seeking to reduce the overall quantities of antibiotics being used. Evidence has shown that these actions will slow the rate at which resistance develops, preserving the effectiveness of existing treatments, and may even help certain antimicrobials to recover their effectiveness. The action plan sets out a structured framework for working effectively together across all sectors of Irish society to tackle the serious threat of AMR. It presents strategic interventions and activities, with reference to the five strategic objectives established by the WHO, to tackle AMR:

    1. Improving awareness and knowledge of AMR
    2. Enhancing surveillance of antibiotic resistance and antibiotic use
    3. Reducing infection and disease spread
    4. Optimising the use of antibiotics in human and animal health
    5. Promoting research and sustainable investment in new medicines, diagnostic tools, vaccines and other interventions

    In 2015, the FSAI published a report on the ‘Potential for Transmission of Antimicrobial Resistance in the Food Chain’. The main conclusion of the report was that, whilst antibiotic resistant bacteria can be transmitted to humans through the food chain, and the overall contribution being made by the food chain cannot be quantified, action is nevertheless needed in the agri-food sector to combat this growing problem. The report recommends measures aimed at reducing antibiotic use wherever possible through improved husbandry and disease prevention measures and improving surveillance of antimicrobial use and AMR. The report also identified a number of research priorities.

  • What can farmers and food businesses do?

    The development and spread of AMR is a public health threat that also impacts on animal health and welfare as well as the environment. Collaborative action by all stakeholders is required to address this global public health challenge. The first step to address the challenge of AMR is to improve the overall health status of the human and animal population.

    Farmers can use disease prevention strategies to improve animal health. These include improvements to biosecurity, adherence to best practice with regard to production and management practices and implementing integrated disease control programmes. Targets to reduce on farm usage of antibiotics, increased use of vaccines and alternatives to antibiotics should be considered as part of an overall strategy to address AMR. Where it is necessary to use antimicrobials to treat a disease, prudent use is essential to maintain the efficacy of the medicines. Prudent use of antibiotics means that the antibiotics are both prescribed and administered in a responsible manner. This means that the correct medicine is used to treat the particular disease that has been accurately diagnosed, and that the medicine is used at the correct dose rate and correct duration in line with veterinary consultation.

    On farms, improvements in biosecurity practices are effective to reduce animal antibiotic consumption. Research carried out in other European countries has shown that better biosecurity results in less disease, less antibiotic use and better production results in terms of animal health and welfare, public opinion and farm profitability. For practical advice and more information see the Department of Agriculture, Food and the Marine (DAFM) guidance on Agri-food and AMR.

    Food businesses can do their part by supporting and buying from agri-food producers, such as farmers, who adhere to principals of responsible antimicrobial use, namely:

    • Right veterinary advice
    • Right animal that requires antibiotic treatment
    • Right veterinary medicine
    • Right dose
    • Right duration of treatment
    • Right disposal of veterinary medicine

    The overall goal of iNAP is to protect public health by ensuring antimicrobials are only being used in accordance with international best practice. iNAP also recognises that it is essential to use antibiotics to treat outbreaks of bacterial diseases in animals if animal welfare is to be protected, and the spread of zoonotic diseases from animals to humans is to be controlled. For this reason food businesses should not support any move towards lifetime antibiotic free food production systems, but rather seek to promote responsible use of antibiotics in the Agri-food sector.

  • What can the general public do?

    It is clear that antimicrobials, particularly antibiotics, are essential to both human and animal health and it is up to everyone to play their part in using them responsibly to ensure they will they be effective for many years to come. Using antibiotics when they are not needed causes harm, wastes money and creates stronger bacteria that do not respond to antibiotics. Antibiotics are useless against common illnesses such as colds, flu, earaches, tummy bugs and rashes. This is because these infections are caused by viruses and antibiotics don’t work on viruses. For practical advice on how to manage common illnesses such as colds and flus see

  • Further Information on AMR