TAIPEI, Taiwan -- A college girl was found to have had both the corneas of her eyes devoured by amoeba after wearing disposable contact lenses for over half a year without taking them out. 
 
 The girl bought a pair of disposable contact lenses that were supposed to be used for one month and wore them for more than six months, even while she was sleeping. After feeling acute pain in her eyes, she went to hospital and was diagnosed with acanthamoeba keratitis (棘阿米巴角膜炎), which is caused by a protozoon called an amoeba (阿米巴原蟲). The infection was brought on by dirty water that she used to clean her face, doctors said. 
 
 Acanthamoeba keratitis, commonly referred to as amoeba keratitis, usually afflicts contact lens wearers or people whose eyes come into contact with dirty water. 
 
 Director of ophthalmology at Wan Fang Hospital Wu Jian-liang (吳建良) indicated that 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 wounds in the eyes and cultivating an environment suitable for amoebas to survive. 
 
 Wu said that the college girl did not follow the correct procedure in maintaining the hygiene of her contact lenses and her overuse of the lenses gradually damaged her corneas. After half a year of wearing them, her corneas were devoured by amoeba and shrank to half their normal size. Unfortunately, polyhexamethylene biguanide (PHMB) or chlorhexidine, which are considered to be effective medicines in eliminating such amoebas, haven't yet been introduced to Taiwan, said Wu. 
 
 Director of ophthalmology at Tri-Service General Hospital (三軍總醫院) Lu Da-wen (呂大文) warned that no matter whether they are soft or hard, contact lenses should not directly come into contact with water, as this will increase their chances of becoming infected by other viruses and protozoon. 
 
 Lu also stated that cases of acanthamoeba keratitis usually increase markedly during summer, and people should therefore pay more attention to proper hygiene at this time. 

 The cardinal rule when using contact lenses is to maintain proper hygiene. That means cleaning them regularly and disposing of them when recommended. Not doing so can leave the wearer susceptible to infections, which are the smallest of problems to be worried about, considering that 23-year-old Taiwanese student, Lian Kao, became infected by a bug that gnaws the eyeballs after keeping her lenses on for six months straight. 
 
 The microscopic bug that ate up Kao's cornea was the single-celled amoeba Acanthamoeba, which is notorious for the severe infections it causes in the eye, skin, and central nervous system. The parasite is commonly found in soil, dust, showers, and even swimming pools. When it makes contact with unclean lenses, it starts feeding on the bacteria on them, and if they happen to be on someone's eyes, the parasite burrows down to where it can start feeding on the cornea — a condition called Acanthamoebic keratitis. 
 
 Infections of this type are rare. They are hard to detect until the the person with the amoeba in their eye begins to experience acute pain. Early stages of infection may be cured with prescription drugs, but diagnosis is often complicated, delayed, and generally unsuccessful. The Journal of Optometry defines Acanthamoeba keratitis as a blinding complication that results due to wearing a lens past its time. Kao had worn the same lenses for six months, even while swimming, without once cleaning or removing them. This gross negligence cost her an eye. 
 
 According to the Daily Mail, the amoeba had eaten up the surface of Kao’s eyes, breeding in the space between her eye and the lens. The director of ophthalmology at Taipei's Wan Fang Hospital, Wu Jian-Liang 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.” 
 
 The doctors are now using Kao’s story to educate the 34 million Americans and 71 million people worldwide who use contacts. Acanthamoeba is responsible for 95 percent of reported cases of keratitis and doctors urge contacts wearers to exercise preventive measures. Personal hygiene with contact lenses includes cleaning them with commercially available cleaning solutions, avoiding water while cleaning, not swimming, showering, or using a hot tub while wearing contacts, and using one’s own without sharing.
– Doctors hope a horrifying story out of Taiwan will help drive home the importance of proper hygiene for wearers of contact lenses. A 23-year-old student lost her eyesight after buying contact lenses that were supposed to be worn for one month and leaving them in around the clock for six months, leading to an infection by amoebas that gnawed away the corneas in both her eyes, the China Post reports. The microscopic Acanthamoeba parasite is found in environments including soil, dust, and swimming pools, and doctors believe the woman became infected after using dirty water to clean her face. The director of ophthalmology at a Taipei hospital explains the situation to the Daily Mail: "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." As a 2009 study in the Journal of Ophthalmology explained, "Corneal oxygenation is significantly reduced during contact lens overwear, particularly for those who sleep in their lenses overnight." Further, it found that "the association between [the infection known as] Acanthamoeba keratitis and contact lens wear is firmly established; it may account for up to 95% of the reported cases." And while such infections are relatively rare, they are hard to detect until the person feels acute pain, by which time it could be too late, Medical Daily notes.