Frequently on the media, the word “superbug” is used as if it were the new Black Death or the coming apocalypse. What is a superbug and why is it so feared?
Superbug is the colloquial nickname for drug-resistant bacteria. For example, one of the most famous superbugs is MRSA (methicillin-resistant Staphylococcus aureus). This strain S. aureus, a common bacteria found on skin and inside the nose, is resistant to a powerful antibiotic called methicillin and thus very hard to treat. Unfortunately, MRSA is most commonly contracted in hospital settings as patients are vulnerable to infections (e.g. after surgery) and hospitals are perfect breeding grounds for superbugs.
The cause of a “normal” bacteria turning into a superbug is due to the incorrect use of antibiotics. When antibiotics are used, they wipe out a significant portion of the bacterial population but fail to kill all of them in the first attack. The surviving bacteria are the more adapted ones that are able to withstand the harsh environment for a little longer. If the patient stops taking the antibiotics and the bacteria remains, these “drug-resistant” bacteria multiply to create a second infection that is resistant to the drug that was used previously. In fact, this is a classic example of natural selection in motion, except that the environmental change is man-made.
This is the reason why doctors are reluctant to prescribe antibiotics for diseases such as the common cold or viral diseases, as the risk of developing superbugs is greater than the benefit (which is zero in viral diseases as they do nothing) of the treatment. It is also why a course of antibiotics must be finished even if the patient is feeling well, so that even the surviving bacteria are eventually killed.
To show the potential risk of superbugs, the case of VRSA can be taken into consideration. When MRSA was first discovered, doctors found it very difficult to treat but luckily they had a secret weapon – vancomycin, one of the most powerful antibiotics known to mankind. However, they soon found that S. aureus and natural selection easily overcame this through a new strain called VRSA – vancomycin-resistant S. aureus. Here was a bacteria that could overcome the greatest weapon man had against bacteria, all because people were taking more antibiotics than needed and not taking the full course prescribed.
Thus, one of the growing problems of modern medicine is the development of new drugs so that we can make a comeback in the arms race against bacteria.