Did you get a shot? They really DO help.
If for some reason you didn't, can't or don't want to, the VERY best thing to do to not get a sickness that is passed on via mucus membranes (nose, eyes and ears) - you can't get the flu from mouth to mouth contact, those would be stomach and intestinal bugs passed that way.
but whenever you are out in public, DO NOT touch your face or stick your finger in your ears. As soon as you get home wash your hands real good. Also if you come home and were out in public and have to use the bathroom, wash your hands BEFORE using the toilet as I believe that touching the toilet paper and then wiping, transfers germs to mucus membranes "down there" - I ever heard that, it's just MY personal paranoia that I follow, and hey, I don't get sick (and I drive a school bus that is "germ central") so I must be doing SOMETHING right!
If someone in your house is sick, just don't ever touch your face. If you truly are as paranoid and obsessed as I am you WILL remember not to. If you don't remember, then you just aren't as crazy as me.
The mice and hantavirus? Gee, I never even thought about anything like that! People clean out "dirty" things all the time and I never heard of anyone getting something like that. Maybe it's rare. If you are truly worried, wear one of those dust masks.