My number one rule when flying is to never touch your face under any circumstance.  If it is absolutely necessary, use hand sanitizer and be extremely brief.  The problem with airplanes is the recycling of the air.  If one person has a cough, cold, flu, or any type of illness, it will no doubt be picked up in the air and then circulated and circulated until the whole plane gets the illness.

I am probably sounding like the worst germ-a-phobe, but it is absolutely true.  There is no place for the air that we breathe out to go.  They pressurize the cabin, make sure there are adequate levels of oxygen sufficient for those in the plane, and everything else is recycled (probably the worst recycling there is).

If you don’t go to my extreme of never touching your face, at least bring hand sanitizer with you.  Every little bit helps, and I know that no one wants the flu right before they go on vacation.  That is the time that you want to be the healthiest, not having to worry about being ill.  Do your body a favor, and be a little more cautious next time you are on a plane.  The person next to you might be carrying more than just luggage.