I agree with you emotionally, Pam, but not objectively. Driving across the country would likely expose you a greater number of germs. How many total bathroom, food, and hotel stops would you need to make? Even if you packed food and slept in your car, at some point you are going to have to poop, and you are going to have to stop at gas stations to refill your tank.
For a non-negotiable emergency I would fly, but not for any other reason.