Improper contact use causes nearly a million Americans to get eye infections every year, according to the Centers for Disease Control and Prevention.
Most of those infections come from wearing contacts overnight. But they can also be caused by other factors, including a bacteria biofilm (a group of cells that join together), which can form in polyethylene (plastic) contact cases. If you use weekly or monthly contact lenses, your case might be a breeding ground for bacteria, which can colonize in the cornea when you put in your contacts, leading to infection or inflammation.
