71 million people around the world wear contact lenses. Most do it with care. But a 23-year-old Taiwanese woman left her contacts in for six straight months. What happened next sounds like a nightmare from a science fiction novel, but here it is: a microscopic amoeba ate into her eyeball, feeding on her cornea. The amoeba, a common parasite called Acanthamoeba, causes severe infection in the eyes and skin. Leaving contacts in for an extended period allows bacteria to grow on them and that’s what the Acanthamoeba feeds on, until it penetrates deep enough to feed on your eye itself.
According to the Daily Mail, Taiwanese student Lian Kao left her contacts in even when swimming and washing. Doctors removing the lenses found that the surface of the young woman’s eyes had been devoured by the parasite. It’s usually too late, the damage done, by the time symptoms become bothersome to the wearer. There are around 6,000 cases a year of this sort of “microbial keratitis” that can cause vision loss.