But imagine what you thought may have been an eyelash turns out to actually be a worm wriggling around. This was the reality for a teenager in Mexico. The unnamed 17-year-old boy began to feel increasingly intolerable pain in his right eye. His vision also quickly declined, to the point where he could only see hand motions. After three weeks of dealing with the pain, he decided it was time to seek out a doctor, according to his case published in The New England Journal of Medicine. An eye examination revealed a flatworm, that was 3 millimeters (0.12 inches) long...