when someone feels sick i ask them how and if they say anything about v*ing i let them know not to breathe on me touch me or anything until they feel better. only one knows i am emetophobic, the others just consider me a germophobe. but to avoid freakouts and akward things in case a friend is sick i would suggest letting them know of your condition so that they know if they feel ill you are NOT the one to go to. which is not to say you dont care or anything, its just bad for your peace of mind and health if they come near.