About one in every three people who wear contact lenses sleep or nap with their lenses still in, the CDC says.

A 59-year-old man was in the shower, wiping his eyes with a towel, when he heard a popping sound and felt pain shoot through his left eye. His cornea had developed a severe ulcer and ruptured, tearing a hole in his eye.

The ulcer grew from a bacterial infection the man developed after leaving his soft contact lenses in overnight during a two-day hunting trip, according to a U.S. Centers for Disease Control and Prevention case report.