The news seems to arrive every few months, sticking in your head like a nightmare that left you drenched in sweat: yet another person found a cockroach in their ear. It happened to a Florida woman just last month: a cockroach crawled inside her ear while she was sleeping, and she lived with the bug lodged there for nine days before it was removed. Then last week, another Florida resident went through the same ordeal. This time, the roach allegedly laid its eggs before dying. So, why does this keep happening? Why do cockroaches wriggle themselves inside people’s ears, where they’ll almost certainly meet their death?

First of all, cockroaches like to go around during the night, which coincidentally is when people sleep. So by virtue of just lying there motionless, we become likely victims. Cockroaches also like small, warm, humid places. And ears qualify as all of the above. “By going into the ear, that’s like a safe place to eat or rest,” says Coby Schal, an entomologist at North Carolina State University. That’s right: “a safe place to eat.” Roaches might wander inside our ears in search of a tasty snack.

See, cockroaches are attracted by certain types of chemicals called volatile fatty acids, which are released by fermented foods like bread and beer, Schal says. And just like cheese, our earwax radiates these cockroach-wooing chemicals as well. “The smell that emanates from the ear is attractive to the cockroach,” Schal tells The Verge.

just like cheese, our earwax radiates these cockroach-wooing chemicals

The problem is that once the roach crawls inside the ear, it’s likely to get stuck. That’s because once the bug is inside, wriggling its legs, people instinctively scratch their ear, pushing the roach deeper inside the ear canal. Sometimes, the cockroach survives and according to Schal, the common household pest called the German cockroach can live for about a week without food and water. But often times, the scratching squishes the roach dead. “Now you have a ruptured cockroach that’s full of bacteria inside the ear,” Schal says.

That’s what leads to ear infections. The outside of cockroaches is actually surprisingly clean, Schal says, unless the roach has been crawling all over your toilet bowl right before coming to your bed. The critters spend lots of time cleaning themselves. But inside, there’s a concentration of bacteria. Roaches also have spiny legs, so if you push the bug too deep down by using tweezers or a Q-tip, you risk tearing apart your eardrum. That is not only painful, it can also lead to infections and hearing loss. So, the first thing to do if you have a roach infestation and think one bug has found its way inside your body is to go see a doctor, says entomologist Joe Ballenger. “The ear is a delicate organ,” he tells The Verge.

Before extracting the roach, doctors will generally kill it if it’s still alive, by either using mineral oils or a numbing drug called lidocaine. That could cause some problems though, says Schal. Some chemicals that kill cockroaches make them poop and barf before they expire their last breath. “It tends to defecate and regurgitate, both of which are not good to be happening inside someone’s ear,” he says. “It emits all sorts of bacteria, fungi, and nasty stuff.” But a doctor will clean the ear after removing the intruder, so roach puke and excrement shouldn’t be a concern.

Some chemicals that kill cockroaches make them poop and barf

Cockroaches are obviously not the only bugs that find their ways into our ears — but they are the most common offenders. That’s because roaches live around people, feeding off our garbage. A study published in 2006 reported 24 cases of patients with “ear-invading” bugs over a two-year period in South Africa. Cockroaches accounted for 42 percent of the insects, followed by flies and beetles. (There were also moths and ticks.) Another study published in 1993 listed the objects extracted from the ears of 98 patients at a hospital in Los Angeles county over the course of one year: cockroaches were number one, with 43 cases, followed by bread, cotton, and other objects like “portion of syringe,” a garlic clove, and a popcorn kernel.

For the record, the intruding roaches are usually German cockroaches, which can be up to 0.6 inches long (1.5 centimeters). The larger American cockroaches, which inhabit sewers, are way too big to fit inside an ear, but their young might, Schal says. (Both are found all over the US.)

Fear that a cockroach will crawl into your ear shouldn’t keep you up at night, says Ballenger. “It’s one of those things that’s a little bit of a freak accident,” he says. “It’s not common enough for people to worry about.” It’s a freak accident that makes you shiver, though. And that’s why we keep hearing in the news about (mostly Florida) people getting roaches stuck inside their orifices. “It’s that yuck factor,” says Schal. “It sounds like it’s happening all the time but it’s really not.”

“I get why it freaks people out.”

Still, even entomologists — who handle insects for a living — are grossed out by the idea. Ballenger says he sometimes goes “black lighting,” which involves shining a light against a white sheet in the middle of a field at night to attract as many insects as possible. (“Some people like rollercoasters. We like those sorts of things,” he says as an explanation.) In the frenzy of bugs storming by the light, it happens that one bumps against his face, he says. In that context, if one critter got inside his ear, Ballenger says he’d be fine. But having a cockroach crawl inside your ear as you sleep in your bed? That’s another story. It’s like an invasion of privacy, and definitely off limits.

“I get why it freaks people out,” Ballenger says. “Totally understandable.”