The reports estimates that there are nearly 1 million patient visits to doctor's offices, clinics and hospitals for treatment of an infection of the cornea called keratitis (kehr-uh-TEYE-sis). Most cases are mild irritations or redness, but a very small number are severe and can lead to blindness.
The Centers for Disease Control and Prevention released the report Thursday.
CDC officials say keratitis often occurs when contact lenses are worn overnight or are not properly cleaned or stored.
About 38 million Americans wear contact lenses. Other researchers have estimated 1 to 10 per cent suffer keratitis or other eye problems.
CDC information: http://www.cdc.gov/contactlenses/