Have you noticed something different about Bob Costas who's anchoring the Olympics? He has an eye infection that is getting so bad that he has the night off tonight.
The problem? Conjunctivitis, an itchy painful type of cold virus that almost every kid gets eventually, commonly called "pink eye", and it is very contagious.
"It's more related to those closed scenarios where you are in a plane which probably wasn't as sanitized as everything else is and your sharing pillows or other materials with other people that have viruses of the cold virus that you may have caught," says ophthalmologist Rishi Singh, who is with the Cleveland Clinic.
Dr. Singh also says you can even get pink eye touching a door knob after someone else who is infected, which is why frequent hand washing is so important, especially before you rub your eyes.