The primary active ingredient in hand sanitizer is ethanol. Ethanol kills 99.99% of the bacteria it comes in contact with, Hand sanitizer also contains isopropyl alcohol. The first obvious use is to clean your hands.I Squirt some on and rub it all over after filtering water from a stream or lake. Clean your hands before mealtime, and after you use the privvy. For health purposes, it's important that you burn this routine into your mind so you don't catch a bug that can ruin your trip.
Hand sanitizer can also be used as a convenient fire starter in an emergency. It can be used to clean utensils and sterilize equipment like sporks and knives. It can clean scrapes and small wounds to help prevent infection.
It is important that you buy the unscented variety of hand sanitizer. Anything scented will attract animals, like bears, which can mistake unnatural scents for food.