Until something develops a resistance to that. A routine part of research is exposing bacteria or other single-celled organisms to something that kills them. Sooner or later, one little bastard lives and that starts the resistance. We've done it with drugs, cold, heat, etc. That way we can use those genes that allow those strains to be resistant as marker genes for other experiments.

Bacteria have been staying one step ahead of the competition for billions of years. I doubt this stops them.

And honestly, the best thing here is take all the antibiotics your doctor prescribes, at the times prescribed, and finish all the pills. That and don't take antibiotics for things that you don't need them for.