Feeling some kind of discomfort in her left eye while out fishing for salmon, Oregon resident Abby Beckley tried fruitlessly to remove the debris for five days straight. Though she compared it to a stray eyelash, the truth of the matter was much, much worse.
After pulling hard on the area underneath her eyelid that was inflamed, she found a parasitic worm had been yanked out of her eye. Identified as Thelazia gulosa, it can most often be found in cattle, with no confirmed cases of infected humans on record throughout all of medical history.
This begs the question of how, exactly, the worm got there in the first place. Even for the broader Thelazia species, only 10 other cases of infection have been found in human eyes, with the last one coming from over two decades in the past.
To make matters worse, the worm had company. Beckley pulled out five more worms before going to the doctor. After traveling from Alaska to Oregon, pieces of several worms were extracted from her eye and sent to the Centers for Disease Control and Prevention, at which point they were finally identified by staff.
While no one is entirely sure how Beckley became infected with the worms, doctors theorized it may have happened when she recently passed through cow pastures. This species of parasite grows inside the stomachs of face flies, which land on an animal’s eye to drink tears for sustenance. When this happens, matured larvae escape through the fly’s mouth and onto a creature’s eye to produce more of themselves.
All in all, though, these worms are far from an epidemic in the making. If the extreme rarity observed throughout history wasn’t enough of an indication, by the time all the worms had been removed from her eye, Beckley found only fourteen of them. Not a small number when you consider what’s being counted are worms in an eye, but much better than hundreds or thousands.
As one would expect, the best method of treatment is prevention, and the best way to prevent infection is to simply shoo away flies.