Woman Pulls Parasitic Cattle Eye Worm From Her Own Eye
This was the first-known time the parasite has made the jump from cows to humans
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In August of 2016, Abby Beckley felt the tickle of what she thought was an eylash stuck in her eye. But there was no hair causing the irritation. As Erika Engelhaupt reports for National Geographic, it was a worm. Actually, it was many worms.
Beckley figured out this gruesome reality after days of constant irritation. Her eye turned red, her eyelid drooped, but she still had no clue what was going on. Finally five days after the issue began, when the salmon fishing boat she was working on returned to port in Craig, Alaska, she decided to take action. Beckley pulled up her eyelid, pinched at the skin and extracted a tiny translucent worm.
While her find is truly disgusting, it’s also scientifically interesting. Beckley was infested with an eye worm species called Thelazia gulosa. It was the first time this particular parasite had ever been found in humans, writes Engelaupt.
Beckley and her roommate initially believed the worm might have come from the salmon they work with, since those fish can often harbor parasites, reports Sandee LaMotte at CNN. They searched for the condition online but found no connection between salmon worms and humans. And a local doctor had no suggestions. "I could see them moving across my eye at that point, too. There were so many," Beckley tells LaMotte.
Eventually, friends and family convinced her to return home to Portland, Oregon. There, she went to see doctors at Oregon Health and Science University in Portland.
While at first some doctors suggested the “worms” she was finding were just strands of mucus, she convinced them to wait and watch. “I am thinking to myself, 'Worms, please show up,' because sometimes they would go behind my eye and under the eyelid, and you couldn't see or feel them anymore.” She tells LaMotte. After half an hour, the wrigglers made their debut. “I felt one squiggle across my eye, and I told the doctors, 'You need to look right now!' I'll never forget the expression on their faces as they saw it move across my eye.”
Doctors collected samples of the worms and sent them to the Centers for Disease Control, which identified the worm as Thelazia gulosa, an eye parasite found in the U.S. and Canada. But until now, it had only been seen in the eyes of cattle. Beckely’s ordeal is discussed in a new paper in The American Journal of Tropical Medicine and Hygiene.
The study documents the 11th time eye worms infected a person in North America. But it was the first time this particular species, a cattle worm, infected a human. There are two other species of Thelazia worms that infect humans, and Beckley’s infection represents a third species now known to parasitize humans.
So how did Beckley acquire the infection? According to the CDC, eye worms are spread by species of "face flies," which feed on eye secretions. According to Engelhaupt, the worm larvae crawl from the flies into the eyes of the animals they’re feeding on, where they transform into adults and produce larvae. That larvae then need to hop back on board a face fly to complete its complicated life cycle. It’s thought that Beckley, who spends much of her time outdoors, picked up the worms while horseback riding and fishing along the coast of Oregon where cattle are common.
Since face flies normally don’t bother humans, Beckley’s worm colony would have likely died out on its own if she hadn’t noticed the wrigglers. She tells LaMotte she thinks others may have experienced a similar infection but weren’t lucky—or unlucky enough—to pull a worm out of their eye like she did.
“Dollars to doughnuts, there were people in the past that had these infections but were never specifically diagnosed,” William Schaffner, a professor of medicine at Vanderbilt University's Division of Infectious Diseases who not involved in the study, tells LaMotte. “Here, we have someone who developed this unusual infection, and the physicians were interested enough to send the materials to the CDC, where they have extraordinary diagnostic abilities."
Thankfully, 20 days after finding the first worm Beckley tugged the fourteenth and last out of her eye. Her vision is back to normal and the worms have left no lasting damage, except for psychological scars.
While this infection is likely extremely rare, according to a press release, another species of Thelazia eye worm has spread across Europe in recent years, carried by fruit flies. Apparently, flies capable of carrying the worms are also found in New York, but the worm has not yet been found in North America.
Beckley isn’t the only American dealing with parasites in her eye. Earlier this week, doctors in Tampa found and removed a pork tapeworm that nestled into the vitreous chamber of a man’s eye. If the worm died in the eye, it likely would have caused him to go blind. But if it lived and released larvae, they could have gravitated to his brain, turning it into Swiss cheese. Thankfully, that type of infection is very rare and is only caused by eating undercooked pork.