Eye Infection Shutterstock

If you've ever used your contacts past their recommended usage time, this story will probably scare the life out of you.

Taiwanese student Lian Kao, 23, left her contacts in for six months. That was enough time for an Amoeba to literally devour her eyeball, blinding her.

It's a grotesque story, to be sure, but it has plenty of lessons in it for the 71 million of us in the world who wear contact lenses.

The specific bug that caused the problems is called an "Acanthamoeba." It's a microscopic parasite that can cause severe infections of the eye, skin, and central nervous system. And it's found in water and soil across the globe.

Since the bug can be so ubiquitous, you can probably imagine how easy it would be for someone to get it on their contact lenses, or in their eye, if proper cleaning is neglected. That's what happened to this Taiwanese student.

When the amoeba makes contact with lenses that haven't been cleaned, it starts feeding on the bacteria that it finds there. This is when things really get dangerous. The Acanthamoeba then starts to dig down and begins feeding on the cornea, which is very, very bad. The cornea is the transparent outer covering of the eye.Eye Diagram CorneaShutterstock

This condition may be rare, but it's happened enough to have a name. It's called Acanthamoeba keratitis. The small space that exists between the eye and contact lenses is a perfect breeding ground for bacteria, and it ended in blindness for this student.

While a case this intense may be rare, Acanthamoeba keratitis could happen to any of us who wear contact lenses. So it's a story we can all learn from.

The CDC's tips to reduce your risk of this are to regularly visit your eye doctor, stay on your contact lens schedule, don't wear contact lenses in the shower or swimming, wash your hands before you handle contacts, and clean them with fresh solution regularly.