Just to combine the star-trek references with bacteria, many bacteria CAN survive in the absence of moisture--as long as they are spore-formers. In fact, not only can they survive without moisture, but they can survive the complete vacuum of outer space and being doused with radiation. It depends on the bacteria that you examine. In fact, some bacteria are so resistant to environmental extremes, that they served as the basis of the "panspermia" hypothesis for the origin of life on earth...that we are extra-terrestrials derived from bacteria that traveled via astroid or comet (not the Enterprise) to our planet and innoculated the planet with life--which then diversified.
I didn't want to mention spore-forming bacteria (such as anthrax) because I really was trying to allay Starfleet-Grad's fears, and not raise them unduly, about the dangers of thumb-lickers. Do you realize that if the OP reads this, he/she will be wearing a Haz-Mat suit to work from now on?
BTW, on the ET bacteria theory...Does this mean that the Earth is really just one big zit on the face of the cosmos?
On a serious note, listen to Dark Globe above (and your mom). Washing your hands frequently with soap and water is the best and cheapest way to fight illness. Anti-bacterial soaps don't help against viruses (although it's probably good to use them on wounds), and the hand sanitizers contain alcohol which is very drying, especially in the winter.
