Pink eye is an inflammation of the transparent membrane that lines the eye and eyelid. It's most often caused by a virus, but bacterial infections and allergies can sometimes be the culprit. According to the Centers for Disease Control and Prevention, public schoolchildren in the U.S. miss 3 million school days each year because of pink eye. Dr. Tina Ardon, a Mayo Clinic family physician, explains what you should know about this contagious condition. Learn more: https://mayocl.in/49scYxm | Mayo