How to prevent strep throat?

My girlfriend just found out she's got strep, and I've probably gotten infected already. Is there a way to kill it early so it doesn't affect me? I haven't experienced any symptoms but earlier today I was talking and my throat started hurting so I think I might be starting to get an infection. Is there anything extra I can do besides water and vitamins? I'm too lazy to go to the doctor. And I have a bunch of **** to do like all this week so it would totally suck if it further escalated.