Antimicrobial resistance is an inevitable part of evolution
Antimicrobial resistance is a natural, inevitable process, but changing our behaviour and adapting to new conditions can help delay its possibly lethal consequences, writes Pavel Poc.
Antimicrobial resistance - where a micro-organism is resistant to one or more antibiotics - is a topic that comes up frequently. You might be imagining a bacterial monster like in the movies, turning people into zombies, however it’s more a case of a simple infection being resistant to common antibiotics.
Despite receiving treatment, a massive infection remains, the body weakened by an antibiotic that causes more harm than the original bacteria. Those who are lucky are saved by another, stronger antibiotic. Those are who not are affected by a micro-organism that is resistant even to ‘last resort’ antibiotics.
Debates on this issue tend to focus on the causes, consequences and possibilities of dealing with antimicrobial resistance. One simple fact, however, that is not often talked about is this: The development of antibiotic resistance is a fully natural and inevitable process.
Micro-organisms have been developing new chemical weapons and relevant protection for millions of years. We borrowed these weapons and we have been using them so unwisely that it has reduced their effectiveness.
What is the best way to grow an antibiotic-resistant micro-organism? Give them very low, non-lethal doses of antibiotics over a long period of time. This will allow them to gradually develop and share resistance to it.
And how does this happen? There are major discussions over the possible impact of antibiotic abuse in veterinary and human medicine. However, the use of antibiotics in farming to prevent infection, or even as a supplement to animal feed to accelerate growth, is far more dangerous.
In the EU, around 70 per cent of all antibiotics are used in livestock farming. These are gradually diluted in the environment and the food chain to a non-lethal concentration, which allows the bacteria to slowly build up their resistance.
At the same time, we forget the issues of certain pesticides. In some cases, these are antibiotics, or they interact with antibiotics and modify their effects. For example, the (in) famous glyphosate was patented by Monsanto as an antibiotic against a wide range of micro-organisms and as an antiparasitic against the Apicomplex protozoa.
How is that possible? Look at how glyphosate kills plants. It disturbs the metabolic pathway (shikimate pathway), which produces phenylcarboxylic acids and aromatic amino acids (tyrosine, phenylalanine and tryptophan). We mammals have no such thing in our metabolism, but the plants do and so we can kill them with glyphosate. Bacteria, and some protozoa, also have this metabolic pathway.
Thus, by spraying glyphosate everywhere, we are creating an optimal environment for resistance to develop. The mechanism used by a microbe to dispose of glyphosate is similar to that used to fight other antibiotics. We actually teach the pathogens how to resist our own weapons in the future.
Today, antibiotic resistance threatens the effectiveness of our healthcare system. It is costing lives and money and it will continue to deteriorate until we realise that antimicrobial resistance is a completely natural process of evolution; it is not possible to fight it. Organisms will continue evolving, as will their weapons and their resistance.
The problem is that the development of this resistance, which would normally take centuries or more, is being shortened to decades or years. It is our behaviour that caused this and changing it is only way to solve it.
We now have two options. Either we respond to visible warning signals by developing new antibiotics and using them in a way that resistance develops as slowly as possible.
Or, we let it escalate, which would lead to the collapse of medicine as we know it. No, I am not alarmist, nor do I fear World War Z.
However, I am deeply worried about the return of diseases that were once lethal and which we have been preventing with antibiotics. I am deeply worried about every surgical procedure again carrying a potentially lethal risk.
One thing is certain. Even we, noble Homo sapiens, are just pieces on the chessboard of the eternal game called evolution. The key to success in this game is the ability to change behaviour under new conditions. However, it seems that our species is not as good as this game as we thought it was.
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