Lian Kao is a 23-year-old Taiwanese student who became blind from a totally preventable situation. Lian wore a pair of disposable contact lenses for six month without ever removing them even once, according to a report in The Daily Mail.

As a result, a microscopic bug was able to grow in the space between the lens and the cornea and eventually devoured the surface of the eyeball. Extraordinarily, she never removed the lenses for cleaning at any time during the six months.

Apart from regular cleaning, lenses are supposed to be removed when swimming or washing and should ideally not be worn for more than eight hours a day.

Kao did not follow these instructions, and when they removed the lenses, doctors were horrified to discover that the eye surface had been literally eaten away by the tiny amoeba trapped underneath.

Wu Jian-liang, the director of ophthalmology at Taipei’s Wan Fang Hospital, said:

“Contact lens wearers are a high-risk group that can easily be exposed to eye diseases. A shortage of oxygen can destroy the surface of the epithelial tissue, creating tiny wounds into which the bacteria can easily infect, spreading to the rest of the eye and providing a perfect breeding ground. The girl should have thrown the contact lenses away after a month but instead she overused them and has now permanently damaged her corneas.”

He added that the girl’s case was a way of urging others to be more careful if they plan to use contact lenses. Kao has been diagnosed with acanthamoeba keratitis, which occurs much more frequently in the summer months.

The condition develops over several years – but it’s only when it gets to an advanced stage that contacts wearers become aware of the problem. Then they experience symptoms like red, irritated eyes, by which time it may be too late.

Unfortunately for Lian Kao, it seems that for her, it is already too late.