When an antibiotic is taken to combat a bacterial infection, some bacterial cells may possess mutations which make them resistant to the drug. As with natural selection, those bacterial cells which are resistant to the drug will survive even after a full course of antibiotics. You are likely to feel better, and not notice the infection anymore as the number of resistant cells would be negligible. However, these cells will stick around, divide and reproduce. Therefore, the next time you get this infection, there are more of the resistant cell type present and as a result, the symptoms you experience may not clear as the antibiotic will not have the desired effect, destroying the bacterial cell wall. Eventually, your doctor will give you another antibiotic which appears to combat the infection and you continue as usual. However, new mutations in the bacteria may have arisen as the infection grew, and so the resistance continues. Overall, you are left with resistant bacteria which is much harder to target as fewer and fewer antibiotics are able to actually destroy the bacterial cell walls. MORE ABOUT CURRENT SUPERBUG EPIDEMIC (MRSA etc.).
- Talk about resistance spreading from live stock too.
How can we Overcome Resistance?
In order to achieve this, research is underway into new antibiotics which aim to address different bacterial processes than those currently targeted. A novel approach however, is looking to go back to basics and utilise something that has shown antibacterial properties for thousands of years: metals. Silver is used regularly in plasters to prevent bacterial infections in cuts (etc.) so now, scientists are investigating the use of silver in antibiotics. The exact mechanism is not known, but it is thought that as metals are not naturally found in a bacteria’s environment, bacterial cells are not able to form resistance towards them (yet!) and thus, silver can protect against bacterial infections.