Information for consumers

Information for consumers


What is Antimicrobial Resistance?

Since their discovery over 70 years ago, antibiotics have greatly reduced illness and death from infectious diseases. 

Antibiotics are drugs that work by killing or stopping the growth of bacteria. However, as these drugs have become widely used, the bacteria that they are designed to kill have changed so that the drugs are no longer effective against them. That is, that the bacteria have become resistant to the antibiotic. It is a change in the bacteria, not a change in the patient or the drug that causes antibiotic resistance. 

Bacteria are microscopic creatures too small to be seen by the eye. They can be found everywhere. Most bacteria are harmless, and many are beneficial to human health. Some however can cause disease, and are called pathogens. We prescribe antibiotics to try to kill these harmful bacteria. Bacteria have been on the planet for billions of years, and they are good at adapting to survive. Antibiotic drugs are just another challenge that they need to overcome by adapting in order to survive. Bacteria adapt, often by changing part of their genetic make up, so that they can ‘resist’ the effect of the antibiotic drug. Once this change occurs, the resistant strains of bacteria will be more likely to survive than the strains that are susceptible to the antibiotics in the presence of antibiotics. 

Although this discussion has referred to bacteria and antibiotics, the same can be said for viruses and antiviral drugs, fungi and antifungal drugs and parasites with anti-parasitic drugs. Collectively we often refer to these microscopic organisms as ‘microbes’ and we call the drugs that act of them ‘antimicrobial’ drugs. 

Why is Antimicrobial Resistance important?

Infections caused by antibiotic resistant bacteria are more difficult to treat. The drugs we need to use are generally less effective, more toxic and are often more expensive. Patients with infections caused by antibiotic resistant bacteria are more likely to stay in hospital for longer and develop more side effects from their treatments than people infected by similar antibiotic susceptible bacteria. The greatest concern however is that in some cases there may be no effective antibiotic drugs available to treat the infections at all. Without the ability to confidently treat bacterial infections with antibiotics, we will face much higher risks from medical procedures such as surgery, chemotherapy, transplants, and even safe obstetric care.

If antibiotic resistant bacteria occur in one person, it is possible that these bacteria may spread to infect other people. Transmission can occur in many different ways. This can cause ‘outbreaks’ of antibiotic resistant infections. 


The Centers for Diseases Control in the USA estimate that each year, at least 2 million people become infected with bacteria that are resistant to antibiotics and at least 23,000 people die each year as a direct result of these infections in the USA.

What is Antimicrobial Stewardship?

In simple terms, it is antibiotic use that promotes antibiotic resistance. Antibiotics are one of the most commonly prescribed drugs in human medicine. In Australia, we know that about 50% of people are prescribed at least one antibiotic each year. What is of serious concern is that a great deal of antibiotic use is in fact unnecessary or inappropriate. This use of antibiotics when they are not required means that more bacteria are being exposed to the drugs and get an opportunity to develop resistance to the antibiotic. 

By limiting unnecessary antibiotic overuse we can help to limit the development of antibiotic resistance.

Antimicrobial stewardship is a term used to describe any activities that aim to optimize the way that we use antimicrobial drugs. It aims to rationally use them to treat or prevent infections when we need them, and avoid using drugs when they are not necessary. 

Share by: