Antibiotics have been in use for less than a century. During that time their use has caused resistant strains of bacteria to develop. The process is that with sufficient use, eventually not all bacteria are eliminated by the current antibiotic so as it is used, it kills all non resistant strains, but leaves the resistant strains alive to reproduce. Then a new drug is developed, but the process continues so that now, the bacteria we deal with are not the same as they were before we started this snowball rolling.
During that same time frame, humans have been reproducing and those who would not have survived without antibiotics have had the opportunity to reproduce.
So entering the post peak world, we have a population "weakened" from the lack of "selection" and at the same time have very different bacteria with which to contend. Bacteria and humans have been taking different paths so to speak, so what will happen should antibiotics not be available in post peak times, and these "new" humans and "new" bacteria must again establish a balance?
Somehow I think that bacterial infection will be a much bigger problem to humans than it was before anyone heard of antibiotics.



