Right. And then you might transfer it to your face, and then it might make it into your nose. But that's rare. (As evidence of this, look at how many people Duncan was in contact with outside the hospital, _while_ he was contagious - and none got it.)
Honestly a lot of this reminds me of the "you can catch AIDS from toilet seats!" paranoia in the 1980's. COULD you catch HIV from a toilet seat? Sure, if a carrier had a festering sore on his butt and you had a cut in exactly the same location when you sat down. But the odds are pretty astronomical, and fortunately we didn't give in to the panic and ban gay men from public bathrooms. (And the solutions to that are both boring and mundane - clean the toilets, wash your hands, take care of minor cuts.)