Question: How will we be cured from disease in 20 or 30 years time if we are supposed to have become immune to antibiotics then?

Martin Archer answered on 13 Mar 2013:

Antibiotics are used against bacteria and the problem is that more and more bacteria are becoming resistant to them. The reason for this is essentially evolution by natural selection. Some bacteria will randomly mutate in such a way that a given antibiotic doesn’t affect it. This means it will survive whilst all the non-mutated bacteria will kill off. The mutated bacteria can now multiply, creating more resistant bacteria and eventually they will spread to someone else. With time the bacteria resistant to that antibiotic (called a new strain) will be pretty wide spread and scientists have to come up with a new antibiotic. So you see there’s not much we can do, anything we come up with there will eventually be some sort of mutation that can combat it.

Of course the same is true of our immune system, it tries to make new sorts of antibodies to combat all the new strains of bacteria (and viruses too). That’s why we tend not to use antibiotics so much anymore because our immune system is the best fighter of diseases generally. So I guess we’ll mostly trust in our immune system more but do everything else we can to give it a good chance, without resorting to antibiotics.