A lot of people cough and sneeze on a daily basis, and while most people would believe that just by spacing yourself away from the sneeze of cough a bit, that you'd be free of the bacteria that the person spews out into the air.
As it turns out, laboratory testing with slow motion cameras has proven that the fluids full of bacteria that spew out of your mouth and nose can travel as far as the distance of a classroom, and that air vents can even suck up these particles and move them even further.
What this means for everyone else around people that sneeze or cough is that even being on the opposite side of the room doesn't relieve you of the burdens of potentially catching the illness. Fortunately, if they cover their mouths, it does break some of the travel and reduce its distance.
Overall, not only is the notion gross, but it reminds us just how important it is to cover our mouths when we have to sneeze or cough; and more importantly, use your arm and not your hands, which you touch everything with.