Almost half of antibiotic prescribing for surgery is inappropriate: Report

Inappropriate antibiotic prescribing around the time of surgery and long-term prescribing in aged care are among a mixed bag of findings of a recent report into antibiotic use and resistance in Australia.

The report shows while fewer antibiotics are prescribed in the community than a decade ago, there is still room to improve antibiotic prescribing in hospitals.

We are both involved in antibiotic stewardship programs, primarily in hospitals, which aim to improve the use of antibiotics to improve patient care and reduce the potential for antimicrobial resistance.

Here’s why antibiotic resistance is so concerning and what the latest report tells us. 

Why is antibiotic use and resistance important?

Factors driving antibiotic use tend to be different in hospitals and in the community.

 

In hospitals, there are more patients with infections, and these are also places where patients come to with resistant infections. Here, a common dilemma is making sure sick patients receive antibiotics quickly, balanced with not overusing them unnecessarily.

In the community, GPs often have to use careful clinical judgement to determine whether antibiotics are required, or if the patient will recover without them.

 

If we think of this issue at the level of individual patients, the risks may feel small. But at the population level, using the wrong antibiotic, or using it when it’s not needed, or for too long increases the risk of antibiotic resistance.

This is where bacteria become resistant to the usual treatment options, so infections may continue to progress despite treatment.

This occurs due to “selection pressure”. This means the bacteria acquire changes that enable them to evade the effect of antibiotics, and these resistant strains continue to grow and spread.

Why are antibiotics used in surgery?

Antibiotics are mostly used around the time of surgery as one way to prevent, rather than treat, an infection.

They are generally needed only for procedures where there is a higher risk of infection and for a short period (mostly a single dose before surgery or for up to 24 hours afterwards).

This report shows that just under half (42.7 per cent) of antibiotic use for surgical procedures was not appropriate. The main areas that we need to work on are:

• only using antibiotics for surgery where there is a high risk of infection
• the time we administer the antibiotic dose, ideally within an hour before the skin is cut
• the choice of antibiotic – sufficient to cover the organisms that could cause infection, but not unnecessarily broad that it may cause side effects or antibiotic resistance.

Inappropriate antibiotic use in surgery may have several consequences.

Giving the antibiotic at the wrong time (too early, or too late) reduces its effectiveness. Giving it for surgery where there is a low risk of infection, or for too long unnecessarily exposes patients to the risk of antibiotic side effects such as diarrhoea, as well as increasing the risk of antibiotic resistance.

How about aged-care facilities?

The report shows residents of aged-care homes receive high amounts of antibiotics.

Two striking statistics were that four in five residents (79.5 per cent) received at least one antibiotic prescription each year. About one in three patients (34.7 per cent) were given an antibiotic for more than six months.

Aged-care residents are at a higher risk of developing infections and it can sometimes be harder to spot the signs and symptoms of an infection.

So using antibiotics to prevent infection can sometimes be appropriate but should be a last resort. This is because infections that “break through” to cause infection despite preventative antibiotics are more likely to be resistant.

What else did the report find?

The report also included critical antimicrobial resistances. These microorganisms are a serious threat to some of our last-line antibiotics. These are very difficult to treat and require specialised antibiotics and medical care.

The reported number of these organisms more than doubled from 2022, to 3,389, or more than nine cases each day, in 2024.

The report also highlights that many of these organisms are acquired overseas, reinforcing the regional and global context of antibiotic resistance.

What can we do to reduce antibiotic resistance?

We’ve previously written about actions we can take to reduce antibiotic use. This latest report reinforces that we should:

• raise awareness that many infections will get better by themselves, and don’t necessarily need antibiotics
• for aged-care residents, regularly review medications, including antibiotics, and check if they are still needed
• use the antibiotics we have more appropriately and for as short a time as possible, supported by appropriate oversight in hospitals, and at state and national levels
• continue to monitor for infections due to resistant bacteria to inform control policies
• reduce cross-transmission of resistant organisms in hospitals and in the community
• prevent infections by other means, such as clean water, sanitation, hygiene and vaccines
• continue to develop new antibiotics and alternatives to antibiotics, and ensure the right incentives are in place to encourage a continuous pipeline of new antibiotics.

The wider context

This report is only one part of the picture of how and where antibiotics are used in Australia.

We have previously estimated that around 60 per cent of antibiotics in Australia are used in animals.

This issue was highlighted by recent use of the antibiotic florfenicol in Tasmanian salmon farms. This is closely related to chloramphenicol, an antibiotic used in humans.

This reinforces the need to take a co-ordinated strategy across different sectors, an approach that has worked before in Australia.

There would also be benefits from responding to antibiotic resistance in a similar way to how we respond to other public health threats. So bringing the national response into the Australian Centre for Disease Control, which was launched officially at the start of 2026, should strengthen our efforts.