What do antibiotics do exactly and why do people grow resistant to them?
In: Biology
Hi 🙂
> antibiotics do exactly
They are poison. Bacteria can not grow in poison and die, or at least grow slower so our immune system can win the battle more easily.
As they are “poison”, you get side effects.
The trick is to develop antibiotics that are very effective against bacteria, but don’t cause much trouble for our body.
The classic example: If you let bread sit in a petri-dish, it will grow fungus. The fungus produces poison. Bacteria can not grow where the fungus grows. (Flemming, 1928, discovered the effect of Penicillium notatum.)
> people grow resistant
People do not grow resistant to them, but the bacteria.
They multiply and sometimes some will survive. If these can multiply again, you get resistant strains eventually.
Especially if you stop taking the antibiotics prematurely (“I feel better so I don’t need the rest”). The decreasing amount of “poison” will allow more bacteria to survive, multiply more, get a higher chance to become resistant.
And then you’ll pass them on, if you’re going to work too early and without taking your medication to the end.
Bacteria reproduce rapidly. And if there’s some mutation (error when copying their “code” during reproduction) that can result in them being more resistant to the used antibiotics. Those will survive.
Existing bacteria doesn’t just get resistant. It’s their “offspring”. What can take thousand of years for animals, humans, can happen in a few hours/days with the rapidly reproducing bacteria.
Another issue is taking antibiotics without reason (e.g. some people taking them when having a VIRAL infection. Or chicken farms using antibiotics as precaution, just because it’s cheaper than dealing with a possible outbreak). This will increase the chance of some bacteria developing a resistance to that antibiotic.
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