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.