I think that what is important to note is that their only evolutionary advantage, and thus the main reason they spread, is their resistance to antibiotics, in n

I think that what is important to note is that their only evolutionary advantage, and thus the main reason they spread, is their resistance to antibiotics, in normal conditions they would have a quite big chance of losing in competition with other bacteria. As soon as antibiotics are used, the competition dies and they can proliferate. This means that the best prevention method is to use antibiotics as rarely as possible. Let's remember that the same bacteria that cause infections, can ordinarily live on our body quite harmlessly.