This odd medical diagnosis was described as a “world first."

It started when a 29-year-old woman, identified by her surname He, was in unbearable pain and could not stop tearing up. Her eye was swollen shut and she was confused about why an issue she thought was an infection kept getting worse, CTS News reported.

That’s not what doctors at Fooyin University Hospital in Taiwan, where He received treatment, found. Instead, while looking at He’s eyes through a microscope, Hung Chi-ting, the hospital’s head of ophthalmology, witnessed something he hadn’t seen before.

Insect legs were wiggling from one of her eye sockets.

He yanked out a small bee, known as Halictidae, or a “sweat bee.” And it was alive.

The doctor wasn’t done. Soon he extracted a second sweat bee. And a third.

And, finally, a fourth bee was pulled from the woman’s eyelid.

Craving salt, the bees had been feeding off He’s tears, the doctor said at a news conference last week. The insects had made a new home under He’s eyelid — that is, until they were all removed alive.

“I saw something that looked like insect legs, so I pulled them out under a microscope slowly, and one at a time without damaging their bodies,” Hung said, according to Business Insider Singapore.

How did the bees get in He’s eye?

Hung suspects it all started the previous day. As He recounted in the news conference, she was taking part in the Qingming Festival, also known as Tomb Sweeping Day.

“I was visiting and tidying a relative’s grave with my family," He recently told reporters. “I was squatting down and pulling out weeds.”

As CTS News reported, He said she felt something get in her eye. Thinking it was only dirt, she cleaned her eye out with water and did not rub her eyes much for the rest of the day. She didn’t think much of it until her eyes began to swell up that night and she experienced a stinging pain that made her tear up.

It would have been very likely for sweat bees to be around He at the time, Hung told reporters, as they tend to nest near graves and in the mountains.

At the hospital the following day, when Hung discovered that the sweat bees were feasting on He’s tears, the doctor was relieved that the woman, who wore contacts, had not rubbed her eyes excessively when the pain worsened, Hung told the BBC. If she had, it could have worsened her inflamed cornea or potentially led to blindness, Apple Daily Taiwan and other media outlets reported.

A ‘first case’

Matan Shelomi, an associate professor of entomology at National Taiwan University, told The Washington Post that he had never heard of sweat bees infesting a person before the recent incident.

“To my knowledge, this is the first case of a bee or a wasp getting caught in a part of a person’s anatomy, as far as I know,” he said. “I’m sure the sweat bees got by the eye and got squished between the eye and eyelid. They were in the wrong place at the wrong time.”

In addition to needing pollen and nectar like other bees, Shelomi said, sweat bees, which are dark-colored and metallic, will occasionally need salt to supplement their diet. A study this month from the Kansas Entomological Society found that sweat bees also look to tears as a protein source.

“They don’t seem to be bothered by people, so they will go to any source of salt," Shelomi said. "I think they’re kind of dumb if they come to humans for their salt. They haven’t figured out what we are.”

While there are more than 1,000 species of sweat bees in the United States, Canada and Central America, according to Terminix, they are almost painless and sting only when they are provoked. On the Schmidt Sting Pain Index, a scale of relative agony caused by sawflies, wasps, bees and ants, the sweat bee comes in at the lowest level of pain. Described by the index as “light, ephemeral, almost fruity,” the puny sting is compared to “a tiny spark [that] has singed a single hair on your arm.”

“She couldn’t have asked for a better bee to sting her in her eye,” Shelomi said.

He was discharged and is expected to make a full recovery, KRON-TV reported. The bees are still alive, Hung told the BBC, and will now be studied.

“This is the first time in Taiwan we’ve seen something like this,” the doctor said.

Even though the case is probably the most unusual he’s heard about in his time studying entomology, Shelomi emphasized that what happened at the gravesite in Taiwan was a fascinating but not worrisome “freak occurrence.”

“The woman will be fine. The bees will be fine,” Shelomi stressed. “This is not something that people need to concern themselves with. I don’t expect we’ll ever see it again.”

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