Paulo Whitaker / Reuters

Bee stings hurt like hell, but there’s reason to consider yourself lucky if a venomous prick is the worst you’ve suffered from bees. Last week, Taiwan’s CTS news channel reported that a 29-year-old woman had gone out for a walk in the mountains and returned home with eye pain that wouldn’t go away. The next day, an ophthalmologist pulled four bees—all still alive—from under her right eyelid.

It might seem unbelievable that anyone could last the night with four bees lodged in the eye, but these specific insects were smaller than the common buxom bumblebee. As Hung Chi-ting, who treated the woman at Fooyin University Hospital, in Taiwan, explained at a press conference, these dark-colored bees were ant-size members of a family known as Halictidae. Colloquially, they’re called sweat bees, named after one of their favorite foods.

Sweat bees have more complex digestive and detoxification systems than other bee species. They feast on pollen and nectar like their more recognizable cousins, but they also count salt and moisture as important parts of their diet. And while they’re known to seek out these nutrients from numerous sources, including animal sweat and rotting corpses (the hike during which the Taiwanese women picked up her sweat bees was actually a ceremonial visit to a wooded grave site ahead of the annual Qingming festival), researchers believe that humans’ exceptionally high sodium intake makes our sweat a gourmet treat of sorts for sweat bees. You might have even fed them before without knowing; they’re easy to mistake for a fly landing on your arm, and their stings are milder and less easily provoked than those of, say, a wasp.

One sweat bee in the eye might be written off as an insect with bad aim—but what about four? Researchers who spend time studying sweat bees and other salt-loving insects have, over the years, brought academia to the Fear Factor realm and allowed (mostly stingless) critters to drink tears directly from their own eyes to conduct close-range research. In a 2018 study, Hans Bänziger of Chiang Mai University found that various types of salt-sucking bees expressed a clear preference for tears over sweat. The likely explanation: Tears contain 200 times as many concentrated proteins—and generally higher levels of salt—than sweat.  

But even when they’re not after salt, some creepy crawlies just can’t seem to get enough of the human eye. Lest the sweat bees bask in all the glory alone this week, here are some of the other awful living things humans have had removed from their eyes, ranked from least grotesque to unequivocal worst. Even if you end up with a sweat bee stuck in your lid, you might still be one of the lucky ones.

1. Eyelash Mites

Surprise! You might have little microscopic mites living on (or in) your eyes right now. Demodex folliculorum and Demodex brevis play around in your follicles, feed on secretions from your pores, and come out at night to mate—picture your own Whoville on your face. They’re natural and common, and only become a serious problem if allowed to proliferate enough to cause irritation, thanks to things like dirty sheets and infected eyelash extensions.

2. Ticks

Ticks want your blood, not your sweat, so they’d have little business getting inside your socket. But in a few recorded cases, ticks have climbed aboard right at the threshold, on the edge of victims’ eyelids. Removing a tick from an eyelid requires great finesse, and can be stressful—ticks dig deep, and one wrong move during removal can lead to worse injury.

3. Pubic Lice

In 2016, a 41-year-old Indian woman living in overcrowded New Delhi needed treatment when a pubic-lice infestation migrated to her eyes. Pubic lice are more common in impoverished areas where public-health conditions make hygiene difficult or inaccessible; their spread to facial areas is rare but not unheard of. In this woman’s case, she lived with her discomfort for three months before seeking help, at which point doctors removed at least three lice and multiple eggs from one eye alone.

4. Beetles

A man in Singapore was walking down the street in 2005 when he felt something hit his eye. He washed it out immediately, but his eye continued to swell and itch. Doctors found that an entire beetle had embedded itself in layers of tissue on the inside corner of his eye. The bug was so big that it had to be removed in two pieces.

5. Parasitic Worms

While fishing in Alaska three years ago, a woman from Oregon named Abby Beckley thought an eyelash had fallen into her eye, but when she was able to get to a mirror that evening, she found nothing. Digging around desperately after five days of discomfort, she yanked out a small, translucent worm, still writhing around on her finger, from underneath her lid. Beckley had become the first-ever human campground for a parasite worm known as Thelazia glucosa, commonly seen in cattle’s eyes. And they multiplied. After 20 days and two hospital visits, Beckley reportedly pulled a total of 14 worms out of her eye.

6. Botflies

As a family of insects, botflies are horrifying even before the eyes are involved. Different species of the parasites have different preferred targets, but the mechanism remains similar: An adult lands on some creature and digs to bury its larvae under the victim’s tissue, where it has a chance to incubate and then burst out weeks or months later in a gory spectacle. While cases of human-seeking botflies embedding larvae in eyes are rare, dozens of cases of sheep botflies in eyes have been reported in places where farming is a common occupation. Thankfully, in all reported cases, the larvae were removed before they hatched.

As for sweat bees, this may not be the last time they sneak into an eye. There are nearly 1,000 types of sweat bees, living all over the world (roughly 50 are hunkered down in Florida alone), and, at least in Great Britain, climate change is expected to both spread sweat bees to areas they’re usually not found and increase their foraging behaviors. The chances of one moving into your eye if you’re careful are slim. But from now on, I’ll be hiking with goggles.

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