What is antibiotic resistance? | New Scientist

The discovery of antibiotics and their adoption around the time of the second world war revolutionised medicine. Previously, a sore throat, a bout of diarrhoea, an infected tooth or a minor cut could be deadly. Antibiotics meant that these infections could easily be cleared up in a few days.

This power to treat infections is slipping away. The more we use antibiotics, the more bacteria evolve resistance against them. Often, genes that confer resistance were already present in some bacteria before we started using antibiotics. Even gut bacteria isolated from 1000-year-old Incan mummies were found to be resistant to most modern antibiotics.

When we use these drugs, we kill the bacteria that are sensitive, and the resistant ones survive, multiply and spread. Flies, tourism and cargo ships may all be contributing to the dispersal of antibiotic-resistant bacteria.

As bacteria develop resistance to more and more of our drugs, common infections may become untreatable again in the not-too-distant future. The problem has been exacerbated by the overuse of antibiotics, both in medicine and in farm animals. Cutting down on the unnecessary use of antibiotics is an urgent priority.

Doctors often prescribe a course of antibiotics lasting one or two weeks, and tell patients to finish the course even if they feel better. Recent research suggests that shorter courses are just as effective at killing bacteria and are less likely to fuel antibiotic resistance.

We also desperately need to develop new antibiotics. Governments are investing billions in drug discovery, and these efforts are starting to bear fruit, but with pharmaceutical companies abandoning research on antibiotics in favour or more profitable medicines, big challenges remain to ensure that the pipeline does not dry up completely.

A few compounds have been discovered that make certain antibiotics work against resistant bacteria if they are used in combination. These “resistance breakers” may give us another way to beat otherwise untreatable infections like MRSA.