Suppose that I get a bacterial infection, which my immune system deals with. Are there any remnant bacteria, or are they all gone? Now consider the same scenario, but having been treated with a full course of antibiotics - are there any bacteria left alive? Now suppose I take a partial course of the antibiotics - enough to reduce the bacterial population to a level that my own immune system can deal with by itself. In this last case, if I beat the infection, is there any chance of bacteria having evolved resistance to those antibiotics, or are they all dead?
I ask having recently read an article claiming that conventional wisdom on antibiotics might not be as useful as once thought.