Oh my lordy! This story gets creepier and crazier the more you learn about it.

Back in the summer of 2016, Abby Beckley had been living on an inactive cattle ranch in southern Oregon. "There was just one cow," says the 28-year-old college student.

A few weeks later, she started to have the sensation that something was in her eye. "You know how it feels when you have an eyelash in your eye?" Beckley says. "That's exactly how it felt, but when I looked in the mirror, I couldn't see anything."

The sensation wouldn't go away. And her eye was getting more and more irritated. It was red, droopy and inflamed.

"I finally couldn't take it any[more]," she says. "I went to the mirror and decided I'm going to pull out whatever was in my eye, even if I have to rip part of my eye out."

She pulled down her eyelid and grabbed a clear, threadlike material from underneath her eyeball. Then she looked down at the thread:

"It was squiggling around on my finger," Beckley said. "I thought, 'This is nuts! A worm just came out of my eye.' "

By the time she could see a doctor, Beckley took out four more worms. Some of them were pretty long, about half the length of a paper clip. Mostly, the critters just hung out in the space between Beckley's eyeball and eyelid. But sometimes they crawled right across her eyeball.

"I was just like, 'What the hell is going on? And what in the heck am I going to do?' " Beckley says.

She finally got an appointment with eye doctors at Oregon Health and Science University. At first, they didn't believe her.

"They couldn't find the worms," she says. "And they were saying things like, 'A lot of people, when they have this claim, it's usually just mucus, but wouldn't it be fascinating if there was a worm?' " Beckley says. "I told them, 'Just you wait.'"

Sure enough, an hour later, Beckley felt a worm move. "I said to the doctors, 'Look now! Look now!' "

Immediately the doctors started screaming, "Oh my gosh! Oh my gosh! It just crawled across your eye!" Beckley says. "Then the doctors scattered and started getting ready to take a sample."

The doctors' skepticism is understandable, says Erin Bonura, an infectious disease doctor at OHSU, who helped treat Beckley.

"It's fairly unheard of to have worms in your eye in the U.S., unless you've traveled to a developing country. (For example, one little worm in sub-Saharan Africa, called Onchocerca volvulus, causes river blindness and infects about 37 million people worldwide). And Beckley hadn't," Bonura says. "For this reason, I knew we had to get some of these worms so we could identify them."

The worms more than obliged. Over the next few weeks, 14 worms emerged from Beckley's eyes.

If you think that sounds creepy, just wait till you hear how the worms got in there in the first place. "It's a living nightmare," Beckley says.

Eventually, doctors sent a few of the worms to the Centers for Disease Control and Prevention. Right away, parasitologist Richard Bradbury and his team at the Parasitic Diseases Branch went to work, trying to figure out what they were.

At first, Bradbury thought the creature was a species of eye worm they've seen before in California and Utah, called Thelazia californiensis. "There have been about 10 cases of this worm since 1930," Bradbury says. "So it's extremely rare." (There's a similar species, called the oriental worm, or Thelazia callipaeda, that has infected about 150 people in Europe and Asia — so it's rare, too).

But something didn't seem quite right with that diagnosis, Bradbury says.

"While we were writing up the case, I thought, 'Maybe I should take a second look at that worm,' " Bradbury says. "I quickly realized we were wrong."

The worm from Beckley's eye had never been reported in people before, Bradbury says. To find out what it was, he says, "I had to go back in our reference collection and get a [worm] sample from 1928, with its information written in German."

In the end, Bradbury identified the culprit: the cattle eye worm, Thelazia gulosa. "The life cycle of this worm is amazing," Bradbury says. He and his colleagues published the case Monday in the American Journal of Tropical Medicine and Hygiene.

Basically, male and female worms live on the surface of a cow's eye. They mate and produce tiny larvae. "It's very romantic," Bradbury says. "They create all these baby worms."

This family of worms causes pus to pour out of the cow's eye. And then along comes a fly, lands on the pus and sucks up some of the larvae.

"The baby worms then grow into larger larvae inside the fly," Bradbury says. "And when the worms get big enough, the fly releases them back into another cow's eye — or even a human eye."

In the end, Beckley made a full recovery. Once she removed all the worms, her eye returned to normal. And she doesn't have any lingering psychological scars either, she says.

Unfortunately, for cattle, the prognosis isn't as favorable. They aren't so good at looking in mirrors and pulling worms out of their eyes. The critters hang around much longer and can cause permanent scarring, Bradbury says.

So, basically, a fly spit the worms into Beckley's eye?

"Yes, that's right," Bradbury says. "The fly vomited the worms into her eye."

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