Humanity has made astonishing achievements, and invented spectacular contraptions throughout history.
We travel to space. We invented (or discovered mathematics). Most of us have powerful computers in our pockets (you might be reading this article from one right now, or you use it to look at funny yellow dog pictures). We invented Nintendo, punk rock, and beer, we built giant walls and the pyramids (cue The big bang theory opening theme).
And... we invented a bunch of different ways to fight infections.
Now, each individual has the goal not to die, so a bunch of different animals have been known to use different herbal remedies to treat different health conditions. And that's what we, humans, have pretty much been doing since the dawn of time, until about a century ago.
Fast forward a few decades, antibiotics are widely used to treat a bunch of different conditions. Life expectancy is significantly longer. It seemed like we solved one of the greatest problems of all time.
But, to quote sir David Attenborough: "Anyone who thinks that you can have infinite growth in a finite environment is either a madman or an economist".
And, in a way, antibiotics are a finite resource. Not that we'll run out of them physically, but rather, if we continue to use them as irresponsibly as we have been, more and more bacteria will learn to become resistant. The worst case scenario? At some point in the not-too-distance future, antimicrobial resistance has spread, and millions of people are dying of diseases which used to be cured by antibiotics, such as different bacterial respiratory infections, or syphilis.
How do superbugs develop?
Bacteria are really small. They're barely visible using standard microscopes, their cells are fairly simple and their nucleic acid codes only a handful of proteins. And if it were as simple as that, bacteria would pose no harm to us, and we would have easily gotten rid of them long ago. But, it's more accurate to observe all bacteria as one superorganism. And not only bacteria of the same species. All of them. Bacteria have a complex way of communicating, and, in a way, form a hive mind. They have sex, communicate, cooperate and adjust their behavior depending on their numbers and the environment.
Things get a bit more complicated when we talk about horizontal gene transfer. There are three ways bacteria do this (actually, there are four, but the fourth one isn't important for this story), and those are:
- Transformation
- Transduction
- Conjugation
- Via gene transfer agents (not important for this story)
Transformation is a process in which bacteria uptake the foreign DNA from the environment into their genome. This an ancient trait believed to originate from the common prokaryotic ancestor, important for providing genetic diversity and repairing the damage caused by stress.
Transduction is a process in which a virus transfers parts of the DNA from one cell to another.
Conjugation is a process in which small packages of DNA, called plasmids, are transferred via sex pili from one bacterial cell to another.
So, let's imagine another situation.
Let's say that a person suffers from a common cold. Now, since this is a viral infection, antibiotics will have no effect on the cause. But, let's say that that person takes the antibiotics anyway, as people often do. As they chug down the pills, this person train the harmless, or potentially pathogenic bacteria in their gut to be resistant to that antibiotic. And those bacteria can transfer their genes to other, more harmful bacteria.
Another situation we could imagine is doctors using certain antibiotics without checking if that antibiotic works for that bacteria. Amoxicillin is often prescribed, but it doesn't work on Pseudomonas. Pseudomonas is naturally resistant to this antibiotic. So, not only is the infection not treated, but other bacteria are being trained to become resistant as well.
Taking antibiotics for a shorter period than prescribed, or in lower doses than they should be taken in, basically does the same thing.
What can we do to fight microbial resistance?
In short: avoid any of the situations mentioned previously. The cause of the infection has to be determined, and tested for susceptibility each time. Antibiotics should not be used to treat viral infections. The therapy should be taken for the amount of time prescribed, and in the exact doses which are prescribed.
But, sadly, since we cannot count on common sense (as we have seen during this pandemic, there are people LITERALLY REFUSING to wear masks), scientists are working on alternatives.