Also known as “pink eye” from the redness and inflammation it causes, conjunctivitis is a very common affliction of the cornea that affects millions of people around the world a year. It causes irritation, itching and burning of the conjunctiva, which lines the eyelids, and can have many causes, including allergies, viruses and bacterial infections. Many times, the disease’s symptoms are easily managed and disappear after several days, but in extreme cases, professional treatment may be needed. If severe cases are left untreated, they may worsen and impair vision.