How to STAY AWAY FROM DIARRHEA?

my sisters friend has diarrhea and i been washing my hands a lot and when she like a distance from me i put a towel on my face and breath in it. Like how do i stay away and not make it come to me. PLEASE . i hate diarrhea like what should i do lysol my self and disafect the toilet and door nobs.? what fruits and veggies can i eat from it to make it go away,. thanks