Warnings about the overuse of antibiotics seem to be as common as coughing these days – and now there’s a new “truly frightening” alert that the discharge of drugs and chemicals into the environment is massively increasing antimicrobial resistance.

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The latest warning comes from a new United Nations report which says there’s a ticking time-bomb of drug-resistant germs lurking in the natural environment because of the dumping of antibiotics and chemicals into water and soil.

What this means is that antimicrobial resistant germs in the environment and pollution add another extremely concerning layer to the growing problems caused by global antimicrobial resistance.

But what is antimicrobial resistance, and why should we be worried about it? Here’s what you need to know:

1. Antibiotics and similar drugs are antimicrobial agents that have been used to treat infectious diseases for around 70 years. But the infectious microorganisms (bacteria, viruses, and some parasites) the antibiotics are designed to kill have adapted to them, making the drugs less effective.

2. The World Health Organisation (WHO) says antimicrobial resistance (AMR) is the ability of a microorganism to stop an antimicrobial (such as antibiotics, antivirals and antimalarials) from working against it. As a result, standard treatments become ineffective, infections persist and may spread to others.

3. Bacteria acquire drug resistance partly by exposure to antibiotics. They can transfer, even between different species, genes that provide immunity to the drugs. They can pass these genes on to future generations, or DNA can mutate spontaneously.

4. Microorganisms that develop antimicrobial resistance are sometimes called ‘superbugs’.

5. Antimicrobial resistance also occurs naturally over time, usually through genetic changes. However, the misuse and overuse of antimicrobials is accelerating the process.

6. The WHO says antibiotics are overused and misused in people and animals, and often given without professional oversight. Examples of misuse include when they are taken by people with viral infections like colds and flu, and when they are given as growth promoters in animals or used to prevent diseases in healthy animals.

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7. Resistance to drugs to treat infections caused by Staphlylococcus aureus, which is a common cause of severe infections in hospitals and the community, is widespread. People with MRSA (methicillin-resistant Staphylococcus aureus) are estimated to be 64% more likely to die than people with a non-resistant form of the infection.

8. Antimicrobial-resistant microbes are found in people, animals, food, and the environment (in water, soil and air). They can spread between people and animals, including from food of animal origin.

9. Poor infection control, inadequate sanitary conditions and incorrect food handling encourage the spread of antimicrobial resistance.

10. A 2014 report warned that drug-resistant infections might kill 10 million people a year by 2050, making it the leading cause of death, over heart disease and cancer.

11. Without effective antimicrobials to prevent and treat infections, medical procedures such as organ transplantation, cancer chemotherapy, diabetes management and major surgery become very high risk.

12. The NHS says that to slow down the development of antibiotic resistance, it’s important to use antibiotics in the right way: ‘To use the right drug, at the right dose, at the right time, for the right duration’. Antibiotics should be taken as prescribed, and never saved for later or shared with others.