Up until about sixty years ago people often died from simple infectious diseases. Since the discovery of penicillin, the first ever antibiotic, life expectancies have significantly increased.
The discovery and development of antibiotics represents one of the most important breakthroughs in the history of medical sciences since it provided for the first time a medical solution to previously untreatable ailments. However, nature proved to be more powerful than any therapy, and the spread of antibiotic use brought about the emergence of resistant bacterial strains, mostly as a result of misuse of antibiotics. Today there are almost no antibiotics for which there are no resistant strains, even when combined antibiotics are used. Ironically, hospitals are home to the most resistant and most lethal bacterial strains. The following video describes the various mechanisms by which different bacteria become resistant to antibioitics.
This video was produced by the US Food and Drug Administration
Each and every one of us has experienced an inflammatory condition at one point or another; be it pharyngitis, pneumonia or even a simple inflammation of the eye. The standard treatment for such diseases is antibiotics, which are usually taken for 7-10 days, during which we start feeling better. Problems may start to arise when people don't follow their doctor's instructions. Symptoms usually resolve within a few days, and this leads many people to stop taking their medication or at least lower the dosage, since it can be really annoying to take a pill 3 times a day. We start feeling better and we assume that this means that most bacteria have succumbed to the antibiotics and that our fabulous immune system can take over from here. Well this assumption is simply wrong! This is exactly the critical stage and most dangerous point of the disease, when there might be a few bacteria that developed partial resistance to the antibiotics. If we stop the treatment at this point we are taking the risk that such a bacterial colony will thrive, and when these bacteria attack us (or someone else) the antibiotics would not work at all. So it's very important to follow our physician's exact instructions and never stop treatment without medical advice.
The phenomenon of resistance to antibiotics can be taken advantage of in biological research and development. Nowadays, genetic engineers insert a gene which confers resistance to a particular antibiotic along with the insertion of a gene of interest. This is done to select against cells that do not carry the resistance gene (nor the gene of interest).
How can we deal with the emerging problem of antibiotic resistance in bacteria? First and foremost, we limit the use of antibiotics and educate physicians and patients how to use antibiotics correctly (never stop in the middle of treatment). We also try to use a wide variety of antibiotics in order to kill bacteria that may have developed resistance to certain drugs. When treating a sick person, we start by administering a rather weak antibiotic, and if it doesn’t work we try more and more powerful drugs. Finally, only when these treatments don't work we bring out the "big guns" – those antibiotics that are saved for the really hard cases.
Department of Biological Chemistry
Weizmann Institute of Science