Great minds think alike. Any of the contagious bioweapons will spread like wildfire in a dense city environment. Airports are an easy way to distribute the stuff. The screeners are going to be worthless. The best place to turn the crap loose is at the screening station. Everyone has to pass through.
My employer just put me back on a frequent flying schedule after a long hiatus. Great timing. It totally defeats the point of moving to a small town.