Can Z Pack Be Taken To Prevent Being Infected With Strep Throat?

My girlfriend came down with strep throat just before I was to go on an important business trip. I'm almost certain I was exposed. If I take a z-pack (azithromycin) now, before any symptoms appear, will that also work to prevent me from getting Strep? i.e. will it kill all bacteria, even if they are still in the incubation stage?