The most that a flu virus can live on paper which is a porous surface is up to 8 to 12 hours.
Flu viruses can live longer on non porous surfaces such as metal wood etc for as long as two days before they die.
It's a good idea to wipe surfaces down with Clorox disinfecting wipes to kill off the flu viruses during flu season and always wash your hands often when you have the flu.