…by inhibiting the cell-wall synthesis of bacteria. If bacteria cannot build up their cell-wall, they cannot divide, thus cannot multiply. Lacking an intact cell-wall, bacteria may even commit suicide (called apoptosis).
The dangers of antibiotic resistance
When Penicillin was accidently discovered by Alexander Fleming in 1928, antibiotics heralded the "Golden era of medicine". Since then, these wonder-weapons have saved millions of lives. Antibiotics fundamentally changed medicine and the health of mankind. At last deadly diseases such as meningitis, endocarditis, tuberculosis or puerperal fever were curable.
Even surgery became safe. Before an operation, the patient would receive antibiotics and potential infections during surgery could be avoided, and if not, antibiotics would help.
Today, it is a given that we most probably won't die from a surgery, a lung infection or typhus.
But times have changed.
When A. Fleming discovered Penicillin, he already warned of the potential of resistance. The antibiotic would have to be used with precaution, since it exists as such in nature and so do the resistance genes. Remember, bacteria have always adapted to their environment, explaining their vast diversity and billion-plus years of history on this planet. They are masters in adaption and they will adapt to antibiotics. The more widespread antibiotics become, the more resistant bacteria will arise.
Fleming's warnings weren't heeded. Now, 90 years later, we are facing the 'Post-Antibiotic' era. Antibiotic-resistant bacteria are distributed worldwide. Against every existing antibiotic, there is a known resistant bacterium and there is no perfectly effective antibiotic left. Not only have that, so-called SUPERBUGS carry resistance against every class of antibiotics - you might want to avoid getting infected with one of those.
Antibiotics mostly work in three different ways:
…by interfering with the protein biosynthesis of the bacteria. These proteins are essential for the survival of the bacteria, for example for processing of nutrients, building up the cell wall or for reproduction.
…by sabotaging the DNA replication of the bacteria, thus reproduction. If the bacteria cannot multiply, they aren't a big threat to the host and the host's immune system can keep the bacteria in check.
The bacteria can knock out the antibiotic by either changing the binding target of the antibiotic, by actively throwing the antibiotic out of the cell, or by out-competing or modification of the antibiotic molecules.
These resistance mechanisms are stored in the bacterial DNA as genes. Bacteria can exchange genes among themselves. If a bacterium carrying a resistance against one type of antibiotic meets a bacterium with a resistance against another type of antibiotic, they can have bacterial `sex` and create SUPERBUGS, with multi-resistances against several classes of antibiotics.
Depending on how often you already used antibiotics in your life, you may even already carry resistant commensals in your body.
The resistant bacteria are mostly concentrated in hospitals. The most dangerous superbugs emerge here. The further south you go, the more superbugs you find. In southern Europe, South-America, Asia and India the wasteful consumption of antibiotics is even higher than in the Northern countries, plus the money for practicing with high hygienic standards in hospitals is largely absent in the southern parts of the world.
Human medicine is not the biggest antibiotic consumer though. In the animal-feed sector, the antibiotic consumption is as twice as high as in human medicine. Antibiotics are not only administered for the treatment of infectious diseases, but a large portion is being used for the promotion of growth! Only low doses of antibiotics are used for growth promotion, thus further triggering resistance development.
Then you can add to that the irresponsible handling of antibiotics by the very plants that produce them, who are in turn dumping their waste into the water… (The terrifying story from www.thebureauinvestigates).
Antibiotics only degrade, albeit very slowly. Every antibiotic used, sooner or later ends up in the environment (soil, water, plants). Travelling and international business around the globe spreads the most dangerous superbugs around the world (80% of Indian tourists bring superbugs as a souvenir).
This is an issue that concerns all of us, everywhere in the world.
Antibiotics - Microbiome
Scared yet? Here comes more: I haven´t talked about your microbiome yet…
Antibiotic treatment against, let’s say, a urinary tract infection lasts three to five days, and after one day you already begin to feel better. If you are responsible, you take the antibiotic for all five days, as your doctor instructed you to. What happens in these five days? You most probably took Ciprofloxacin, which killed an E. coli in your bladder. But you did not administer the antibiotic directly to your bladder, you took a pill, right? This antibiotic pill doesn´t know that it should actually just work in your bladder. It also kills E. coli in your intestines, and everywhere else your blood is transporting the antibiotic to. What the antibiotic also doesn’t know is that it should only kill E. coli. Ciprofloxacin is a broad spectrum antibiotic which kills most gram-negative and many gram-positive bacteria, which is to say, you placed an atomic bomb in your gut. Almost no life remains, you killed the non-resistant commensal bacteria and even opted for resistant commensals! They will stay there for the next few years and share their resistance gene with whomever passes by.
A few months later, you might ingest some Salmonellas from the chicken you prepared for your family that day. Your gut microbiome is still that weak enough that a few Salmonella suffice to cause severe diarrhoea in your gut, which is defenceless. Your microbiome had not yet recovered, but it will (eventually) within the next few years, or actually, maybe never…
Now you should be scared!
Not only does antibiotic overuse lead to worldwide resistances, making antibiotics useless in the foreseeable future, antibiotics additionally weaken your microbiome in that way that make you even more susceptible to the next infection, and let's just hope the next one doesn't involve a highly-resistant bug.
What to do now?
We have to wake up!
On one hand it is essential that we do everything to save antibiotics as an effective drug for future generations, on the other hand we have to protect our microbiome by only taking antibiotics when necessary.
For every individual person, the solution is quite easy: think twice before taking antibiotics. Maybe your infection has even been caused by a virus, which makes the use of an antibiotic pointless.
Prophylactic use of antibiotics should only be considered if the risk of an infection exceeds the dramatic side effects! If we all change our habits, we could change a lot.
Nevertheless, this is something that would have to be done collectively and by politicians: global net- and teamwork to contain the resistant superbugs and educational work for the population. Money needs to be invested worldwide in hospital hygiene standards and for research into new antibacterial agents.
It is up to us to do the right thing for ourselves and the future of our children and grandchildren …