> "the ones overused were not useful for humans so resistance isn't actually a factor" First of all, that's not true; there's substantial overlap between agric

> "the ones overused were not useful for humans so resistance isn't actually a factor" First of all, that's not true; there's substantial overlap between agricultural and human use, for example the Bacitracin we use in the U.S. to promote growth in livestock, and the colistin now flooding Chinese agriculture. Second, it wouldn't matter even if you were right; bacteria acquire resistance to classes of related antibiotics. So, for example, when bacteria become resistant to the fluoroquinolones that we regularly put in poultry feed in the U.S., those bacteria will likely be immune to Cipro when they infect you.