zlacker

You are absolutely right, I failed to note that the increased specificity means you lose the broad spectrum effect.

I still think in the cases you describe that they could stand to replace e.g. Vancomycin - BEFORE that fails. The side effect profile for that drug is horrendous: GI bleed, neuro/sensory damage, liver damage, retinal damage etc..

It seems like a blend of phages with slightly varied activity could also reproduce the broad spectrum effect, and CRISPR is going to make that pretty easy I think.

>>dfsego+(OP)
One approach might be broad spectrum antibiotics when urgent and specific bacteria undetermined. In parallel, cultures to isolate the problem, then apply the specific phage to finish the job. Seems like this would prevent or at least hugely reduce antibiotic resistance from increasing.