99.99% i think you’ll find.
The funny thing is that few seem to question, is whether it kills all species to the same 99.99% level… which they don’t. Some bacteria are completely annihilated, others survive relatively unscathed. Whether the one that is unscathed is pathogenic or not is anybody’s guess. Even if the pathogens are always being annihilated, it’s just a few horizontal gene transfers away from passing on that resistance to the pathogenic strain – and then you’re totally unprotected, and have nuked all the niches, meaning the pathogenic bacteria have no competition to take over your whole body.