If you wondered what was wrong with Bob Costas’ eyes during the Sochi 2014 Winter Olympics, the sports announcer was forced by a common eye infection to miss nearly half of the event. “Conjunctivitis,” also popularly referred to as “pink eye,” is a highly contagious infection that is commonly seen among school children. It is caused by bacteria or a virus that inflames the thin membrane (conjunctiva) that lines the eyeball and inner eyelid. The conjunctiva becomes red and swollen, and there is often a discharge from the eye as well as the experience of blurred vision, a gritty sensation, and/or light sensitivity. Viral conjunctivitis, the most common type, usually clears up on its own in about a week.
P.S. While bacterial conjunctivitis is more serious than viral conjunctivitis and may require medical treatment, allergic conjunctivitis is caused by pollen or another airborne irritant and does not resolve until the source is eliminated.