The superpower of bacteria: Antibiotics strike back
Superbugs are called so for a reason, because they really have real superpowers. Only, unfortunately, they promise nothing good to people.
Superbugs are pathogens of infectious diseases that are resistant to several antibiotics that are traditionally used to treat the disease in question. It is the multiple resistance of superbugs that distinguishes them from ordinary resistant strains – they are resistant to only one drug or to several, but from the same class. Superbugs are extremely dangerous, because in front of them we are practically unarmed: literally no drug helps against such infections. Such infections take us back to the beginning of the 20th century, when there were no antibiotics yet, and we had to rely only on the patient’s immunity.
It took humanity several millennia to discover antibiotics. It took the bacteria a little over 50 years to develop resistance to them. And who is then the peak of evolution? Especially when you consider that people themselves contributed to this process. How could this have happened?
In order for bacteria to develop their superpowers, in one place there must be a large accumulation of various strains and types of bacteria, organisms susceptible to them (animals or humans), as well as antibiotics in low concentrations. For this reason, hospitals and livestock farms are ideal incubators for breeding superbugs.
Like any other organism, bacteria constantly mutate. The emergence of many random mutations is the basis of natural selection: if a new mutation allows an organism to survive better in the environment and leave more offspring, then such a gene will become fixed and spread in the population. If not, the mutation is quickly eliminated by selection, since it is not passed on to future generations.
In the case of bacteria, this process becomes extremely noticeable for two reasons. First, many bacteria multiply very quickly. In just a couple of hours, several generations have time to change. And the more intense the reproduction, the faster new mutations appear. Secondly, bacteria have another superpower: they can exchange useful genes with each other using special pieces of DNA – plasmids. This allows bacteria to share important genes not only with their offspring, but also with neighbors. Moreover, such a transfer can occur even between bacteria of different types. This allows new beneficial mutations to spread especially quickly in close communities of bacteria.
It is also important for the development of resistance that the antibiotic is present precisely in small concentrations. If the concentration is high, as it should be during treatment, then the bacteria die immediately, and they have no chance of developing resistance. But if the antibiotic is not enough for cell death, then the bacteria get a chance to multiply and “pump” their superpowers, developing resistance to the drug. If the bacterium multiplies in the presence of several antibiotics at once, then it can develop resistance to many drugs. Such conditions can occur with an incomplete course of antibiotic treatment, with an incomplete prescribed dose (or if an insufficient dosage is prescribed), as well as with frequent unreasonable drug changes.
Disease-causing bacteria remaining in the patient’s body can thus “train”. It is even worse when antibiotics end up in wastewater and other waste, which often happens in livestock farms when antibiotics are used uncontrolled or inappropriately. Here, their concentration falls significantly below the minimum overwhelming, many different drugs are mixed at once, and not only pathogenic bacteria can come into contact with them, but also representatives of flora that are not dangerous for humans. Which is bad, since non-dangerous bacteria also develop resistance and can subsequently transfer it with the help of plasmids to disease-causing brethren. Just perfect conditions for developing multiple resilience.
Supervillains of our time
Superbugs have already become a major public health problem. Back in 2014, the WHO in its report on the problems of antibiotic resistance identified superbugs as one of the global threats. The issues of combating resistance were also discussed during the 71st UN General Assembly, which resulted in the development of a national strategy to combat antibiotic-resistant strains. Goldman Sachs Group, in one of its reports, made a disappointing forecast that by 2050 antibiotic-resistant microorganisms will kill 360 million people, and the economic damage will amount to $ 100 trillion if the world does not take measures to prevent their spread.
The situation with tuberculosis is especially alarming. This infection, even with normal sensitivity of pathogens to anti-tuberculosis drugs, requires long-term treatment. And in the case of strains with multiple resistance, it is necessary to use complex schemes with a large number of drugs, which also do not always turn out to be effective. Then the disease becomes fatal.
Unfortunately, multidrug-resistant strains of mycobacterium tuberculosis are very widespread in the post-Soviet space. This is associated with inadequate treatment of tuberculosis in prisons in the 90s: frequent interruptions in drugs led to constant interruptions in treatment or the use of only one drug instead of the necessary combination of three or five. This, in turn, created excellent conditions for the selection of multi-resistant strains, and poor living conditions and crowded living conditions contributed to their rapid spread among prisoners.
Compounding the general problem of resistance is the fact that over the past 15 years, large pharmaceutical companies have not been sufficiently engaged in the development of new antibiotics, focusing on other diseases. Considering that it takes about 10 years from the beginning of the development of a drug to its release on the market, no breakthroughs in this area should be expected in the coming years. Therefore, the main efforts in all strategies are aimed at slowing the formation of resistance to existing drugs and slowing the spread of resistant strains.
Superweapon against superbugs in the hands of each of us
Unfortunately, doctors are also prone to over-prescribing antibiotics as a precaution or at the insistence of patients, they do not always have the time and desire to explain why an antibiotic is not needed in this case. And some do not even understand this at all. If a doctor has prescribed an antibiotic for you, you can always clarify again whether you really need it, and in no case should you insist on such treatment yourself if the doctor does not consider it necessary.
But taking low doses or premature termination of the course most often occurs through the fault of the patients themselves. The fact is that with many infections, the patient’s well-being improves even 1-2 days before the pathogen is completely defeated. And if a person, feeling an improvement, stops taking the drug, this gives a chance for the pathogenic bacteria remaining in the body not only to take revenge, but also to develop resistance to the drug used. To treat a relapse, the drug has to be changed, and if the patient stops the course again ahead of time, we can already get a strain with multiple resistance. For the same reason, it is dangerous to skip taking the drug: at this time, its concentration in the blood falls below the minimum suppressive one, which again gives bacteria a chance.
The discovery of antibiotics in the middle of the 20th century made it possible to make a real breakthrough in medicine and bring the treatment of infectious diseases to a new level. In the 21st century, we are faced with a new challenge: superbugs can set us back a century and make us defenseless against infections again. And while pharmaceutical companies are engaged in an arms race with superbugs, developing new highly effective antibiotics, each of us must do our part to slow the development of resistance to existing drugs by smartly approaching antibiotic therapy.