Why antimicrobial resistance is a public health threat

Antibiotics save millions of lives every year – but is our obsession with the super drug turning tiny microbes into a major threat?

The discovery of antibiotics a century ago transformed modern medicine, making previously severe or fatal infections treatable, and extending average lifespans by 23 years.

Today, about 40 per cent of Australians are prescribed antimicrobials each year to treat everything from ear and skin infections to whooping cough and meningitis.

But bacteria are beginning to adapt to these medications, making them harder to kill.

That’s called antimicrobial resistance – and here’s why you should be concerned.

What causes antimicrobial resistance?

Bacteria are living organisms that change and evolve over time.

Antimicrobial resistance occurs when germs survive contact with treatments such as antibiotics and antifungals, becoming immune and passing these genes onto their descendants.

Dr Branwen Morgan, who is leading the Antimicrobial Resistance Mission (and development) for CSIRO, says over-prescription exacerbates the problem.

“Over the decades, the overuse and misuse of antibiotics in human and animal medicine is making these drug-resistant germs increasingly common: the more exposure they have to drugs designed to kill them, the more opportunity the germs have to become resistant to them,” Dr Morgan says.

Why is antimicrobial resistance so concerning?

Professor Trevor Lithgow, from Monash University’s Biomedicine Discovery Institute, says a growing number of bacteria and fungi species are displaying resistance.

“We are effectively training the microbes to survive the otherwise deadly effects of these drugs,” Prof Lithgow says.

Without effective antibiotics, infections will be more difficult – or sometimes impossible – to treat, increasing the risk of severe illness and death.

For example, a study by the CSIRO and University of Queensland found patients were almost two and a half times more likely to die from drug-resistant urinary tract infections.

Currently, AMR causes at least 1.2 million deaths worldwide every year.

But the World Health Organization, which has declared AMR one of the top 10 global public health threats facing humanity, estimates drug-resistant diseases could kill 10 million people by 2050.

What can be done to fight AMR?

Associate Professor Deborah Friedman, deputy chief health officer at the Victorian Department of Health, says we need a multifaceted approach to tackle AMR.

This includes preventing infections from spreading via basic hygiene, and limiting inappropriate use of antibiotics in the community, aged care, hospitals and agriculture industry.

“Finally, research and innovation are critical,” Assoc Prof Friedman says.

One recent study found phage therapy – the use of bacterial viruses to clear a bacterial infection – in combination with antibiotics was able to steer bacteria towards a phage-resistant variant that is re-sensitised to antibiotics.

Research has also found adults who eat a balanced diet rich in soluble fibre have lower levels of antibiotic-resistant bacteria.

Professor Lithgow says he’s optimistic a change in community and industry habits will reduce the resistance rate.

“If we change our behaviour, we’ll change the evolutionary pressures,” he says.

How can you help reduce antimicrobial resistance?

Dr Morgan says while AMR is a complex problem, we can still make a difference as individuals by taking a few simple actions:

  • Don’t take antibiotics unless you and your doctor are certain you need them.
  • Get vaccinated where possible.
  • Return unused antimicrobials to the pharmacy, don’t throw them away where they can be released into the environment.
  • Practise good hygiene.
  • Good hygiene: How to sanitise your home safely

Written by Dimity Barber.