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Antimicrobial resistance explainedYou may have heard about ‘AMR’ on the TV or read about it in the paper – but what is AMR and what can be done about it? We’ve taken some of the most common questions about this important health issue and answered them below.

So, what exactly is AMR?

AMR – or antimicrobial resistance – is when a microbe is able to survive exposure to a medicine that would normally kill it or stop its growth. These medicines are called antimicrobials and there are many different types, though antibiotics are probably the most well-known.

Microbes are tiny living things that are often harmless, however some can cause diseases. There are four main types of microbe which can cause a range of infections:

  • Bacteria – e.g. Salmonella

  • Virus – e.g. HIV

  • Fungus – e.g. Athlete’s foot

  • Protozoa – e.g. Malaria

Microbes that survive treatment with antimicrobial medicines can grow and spread, leading to the emergence of ‘superbugs’ that are difficult, or sometimes impossible to treat. A well-known example of a superbug is MRSA: methicillin-resistant Staphylococcus aureus (methicillin being an antibiotic, and Staphylococcus aureus being a bacterium that is resistant to it).

MRSA infections usually occur in hospitals1 and can sometimes spread throughout the whole body, leading to severe disease and sepsis – a life-threatening reaction to an infection.2 Another example is Candida auris, an emerging multidrug-resistant fungus that is spreading rapidly worldwide and mainly affects critically ill patients in intensive care units.3


Why can some microbes survive exposure to medicines designed to kill them?

Microbes, such as bacteria, have been around for billions of years and are constantly evolving. They survive by sensing their surroundings and adapting when conditions aren’t ideal – for example in extreme heat, extreme acidity or exposure to harmful agents.4 So, when microbes in your body are exposed to a medicine designed to kill them, they can mutate in an attempt to survive.

Whilst many of these mutations won’t be successful, some can help the microbe to survive. These resistant microbes are then free to multiply and spread to others – causing infections which are drug-resistant.


If AMR has been happening for a long time, why is there an ‘AMR crisis’ now?

Whilst AMR has been occurring naturally for a long time, human behaviour is making it worse. Today, drug-resistant infections are one of the biggest health challenges facing society.5 Some of the main drivers are:


Misuse and overuse of antimicrobials (e.g. antibiotics)


Lack of access to clean water, sanitation and hygiene for both humans and animals


Poor infection control in healthcare facilities and farms


Lack of access to medicines, vaccines and diagnostics


Lack of awareness and knowledge about AMR and how to take action against it

Each of us has a vital role in helping to stop the spread of drug-resistant infections. Precautions that were recommended during the pandemic like washing your hands regularly can have a real impact, as well as ensuring vaccinations are up to date and using antimicrobials only as prescribed by your doctor.


Why can’t we just make more antimicrobials to stop AMR?

Making new medicines is just one part of the solution. Researchers are hard at work developing new antimicrobials, however this alone isn’t enough to stop AMR. Over time, microbes will continue to evolve and become resistant to the new medicines too.

We can't stop microbes evolving and becoming resistant. But we can change our relationship with antimicrobials and recognise AMR as a health issue we must live with and work hard to keep at bay. An important part of this is reducing the inappropriate use of the antimicrobials we already have to keep them working for longer. 


Why should we care?

AMR poses a real risk to our health and is already having a major impact around the world. More than 1.2 million people died worldwide in 2019 from infections caused by bacteria resistant to antibiotics.6 This is more than the death toll from malaria or AIDS in 2021.7,8

AMR also has a significant impact on healthcare systems and can result in longer hospital stays, ward closures and cancelled procedures.9 In fact, the annual cost of AMR to the NHS has been estimated as £180 million per year.10

Without effective action on AMR, the number of people who die from infections will increase. Everyday medical procedures like caesarean sections, hip replacements, chemotherapy and organ transplants will become very high risk, as any infections picked up during these procedures won’t be treatable.

We need to maintain a global collaborative response before it’s too late. We’ve seen what can be accomplished when industry, government, our healthcare system and academia come together to take urgent action on health threats, and the same must be done for AMR.

If you would like to know more about how you can help to tackle the spread of AMR, read our Change the Course report.


  1. NHS. Conditions, MRSA. Accessed Jan 2023. 

  2. Sepsis Alliance. MRSA. Accessed Jan 2023. 

  3. Ademe, M., & Girma, F., 2020. Candida auris: From Multidrug Resistance to Pan-Resistant Strains. Infection and drug resistance, 13, 1287–1294. Accessed Jan 2023. 

  4. Gao, H., Weitao, T., He, Q., 2011. Coping with the Environment: How Microbes Survive Environmental Challenges. International Journal of Microbiology. Accessed Jan 2023.

  5. World Health Organization. Antimicrobial resistance. Accessed Jan 2023.

  6. Antimicrobial Resistance Collaborators: Murray C, Ikuta KS, Sharara F et al. 2022. Global burden of bacterial antimicrobial resistance in 2019: a systematic analysis. The Lancet. Volume 399, issue 10325, p629-655. Accessed Jan 2023.

  7. World Health Organization. Malaria. Accessed Jan 2023.

  8. UNAIDS. Global HIV & AIDS statistics – Fact sheet. Accessed Jan 2023. 

  9. Dadgostar, P., 2019. Antimicrobial Resistance: Implications and Costs. Infection and Drug Resistance. Volume 23, p3902-3910 Accessed Jan 2023.

  10. House of Commons Health and Social Care Committee. 2018. Oral evidence: Antimicrobial resistance, HC 962. Accessed Jan 2023.

PP-UNP-GBR-3566 / January 2023
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