The problem with airborne viruses is that everybody who dies can potentially reanimate. I honestly don’t know how you beat those numbers.
We need the government to create a virus or bacteria (preferably) that can only be spread by some fluid exchange such as a bite. That should keep the infection rate down at a manageable level.
Are you really bored today? Why not write a letter to your congressman expressing this concern? Tell him or her that the people in charge of the Zombie Apocalypse Project need to make sure infection vectors will not result in an unmanageable problem. Consider throwing in some math.
If you are really, really bored, send copies to the employees of various Departments of Education. They can use the distraction. The less they work, the better for all of us.