@hamburger,
Nods to Hamburger.
Back when I was a bacteriology major, in our first class - bacti 1A, we did tests on ourselves, using soap and water, water, alcohol wipes, iodine, and I can't remember if we used phenol or just were told about it. At least for the thirty or so of us, water came out similarly to soap and water, both leaving plenty of bacteria though not as many as the pre-test bacteria - and alcohol only somewhat less than either of those. Iodine, as I remember, really did the job. And phenol too, although I think it was used in those days primarily as a tool for operating rooms and such.
What soap is good for is taking off oil..