KNOXVILLE, Tenn. (WVLT) -- It's called Acanthamoeba Keratitis, an infection caused by an amoeba that travels through water.
Doctors warn the parasite isn't well-known, but the consequences of getting one are drastic.
Dr. Andy Howard, at the LaFollette Eye Clinic, says it's a dangerous parasite that feeds on the tissue of the eye.
While anyone can get it, Howard says it's more common in people with contacts.
"That space between the eye and the contact lens is a place that this little amoeba really likes to live," he says.
They see about one Acanthamoeba Keratitis infection a year at their clinic. Usually it's caused by someone who isn't taking care of their contacts.
The most common way to get it is getting water on your lenses, Howard says.
"That includes tap water, that includes taking a shower with the contact lenses, even swimming pools and hot tubs are places this amoeba can be found," he says.
Typical symptoms are eye pain, extreme redness and swelling, blurred vision and tiny white spots on the eye.
Sometimes, the only way to stop it is to remove the entire eye.
"The damage can be done and the vision can be lost really quickly. Sometimes within 24 hours," Howard says.
The best way to avoid the amoeba is to follow the instructions for your contact lenses; for example, take them out and change them when you're supposed to.
Howard says to ask your doctor about the best kind of contact solution to use.
"There is no over-the-counter treatment that can cure Acanthamoeba, but if you're concerned at all, an immediate call to your doctor can get you the care you need," he says.
Howard says you should never use water to clean your contact lens case. He recommends rinsing it with your contact solution and letting it completely dry before using it. And he says you should always toss out your old solution each day, never re-use it.