There are some illnesses that have plagued humanity since time immemorial: leprosy, heart disease, cooties, groin rot, groin cooties, groinitis, etc. However, some of the most truly horrible and bizarre diseases reared their heads for one specific moment in history before vanishing just as strangely as they arrived, never to be seen again (we hope). 6. Your Teeth Might Have Exploded In The 19th Century In the 1800s, medical journals started recording instances of people's teeth straight-up exploding. To read the accounts, it's no wonder that Dr. King Schultz went into bounty hunting. Shooting bad guys must have seemed like a relaxing hobby compared to wondering if his patients' teeth were going to shrapnelize themselves into his face. The first recorded case occurred in 1817 with a reverend who, after days of suffering untold agony from toothache, experienced: "... all at once a sharp crack, like a pistol shot, bursting his tooth to fragments, [which] gave him instant relief. At this moment he turned to his wife, and said, 'My pain is all gone.' He went to bed, and slept soundly all that day and most of the succeeding night; after which he was rational and well." This was the template for every case of exploding tooth syndrome (as we're now calling it). Victims would suffer from a tremendous toothache, followed by their mouth detonating from the inside out like baby aliens were inside. In 1830, a Mrs. Letita D reported an aching tooth "terminating by bursting with report," while a dentist in 1871 reported an occurrence of ETS so violent that the patient was knocked to the floor and deafened. Several similar cases later, however, and the condition vanished, never to be seen again. According to a group of researchers, it's likely that ETS was caused by a reaction between hydrogen gas and the metals used in old-timey fillings. In those days, fillings were often made from any combination of lead, tin, and silver, and it's possible that these could have created a low-voltage electrochemical cell (a battery, basically). The hydrogen, meanwhile, could have been created by any part of the tooth cavity that was accidentally left over from the often-poor dental surgery of the time. If the filling created an electrical charge in the presence of hydrogen, a miniature explosion could have occurred, with the tooth providing a handy bomb-like casing. People were essentially walking around with big fat mouthfuls of little Hindenburgs waiting to go off, which they did with terrifying regularity. 5. Chlorosis Exhausted Women (And Turned Them Green) In The 18th Century Doctors have a pretty bad track record as far as being able to correctly identify and treat any ailment specific to women. For example, 18th-Century physicians found themselves baffled by a new malady called chlorosis, which messed with the menstrual cycle and left young women withered and haggard, and turned them green. You can imagine why men were confused. For over 200 years, chlorosis ravaged the young women of high society.Within days of contracting it, they'd fall into a melancholic malaise, rendering them unable to stand or stay awake. They'd also suffer from swollen joints, heart palpitations, "cessation of the menses" (their periods would stop), and -- according to reports of the time -- green goddamned skin. Oddly, it was a classist disease. It only hit women of the upper crust, and rarely, if ever, affected members of the working classes. True to the medical science of the time, doctors blamed the disease on their patients not getting enough dong. This became the leading diagnosis after doctors noticed that chlorosis stopped menstruation. You see, menstrual blood was considered the female equivalent of semen. It stood to reason that the blockage was caused by chastity -- hence chlorosis was nicknamed "the virgin's disease." The real cause turned out to be something a lot less interesting than non-horndoggedness: They were suffering from a form of anemia caused by their terrible diets, a malady that was quickly remedied by regular iron supplements. Interestingly, this was suggested at the start of the outbreak, but it took two centuries for someone to give the idea serious merit. That's like the worst episode of House ever. 4. National Hotel Disease Haunted 1850s Washington, D.C. What's the worst hotel you've ever stayed in? A seedy joint with a coin-operated vibrating bed? A vibrant downtown mecca where businessmen tried to snort blow off your shoulders in the elevators? Or the quaint out-of-towner where that guy tried to shiv you in the shower? Whatever your answer, these pale in comparison to what would have happened if you'd stayed at Washington, D.C.'s prestigious National Hotel in the 1850s. Even worse, you wouldn't have been able to write a scathing online review. For several years, an illness known as "National Hotel Disease" -- the symptoms of which included a swollen tongue, inflammation of the large intestine, violent sickness, and diarrhea -- laid waste to hundreds of dignitaries and politicians who stayed at the hotel, killing nearly 40 of them. Oh, and their symptoms could last for months, sometimes even years after their stay. One victim was President James Buchanan, who caught the disease twice; the first time after he stayed in D.C. following his 1856 election triumph, and the second on a return trip years later (he apparently really enjoyed the hotel, disease notwithstanding). This shouldn't need to be said, but if you stay at a hotel and end up exploding from both ends, maybe don't stay at that same hotel again the next time you're in town. Finding the cause of the outbreak, meanwhile, was just a case of working out what the least stupid option was. The disease was attributed to everything from "bad air" to poisoned rats to the types of saucepans used in the kitchens to the hotel's slaves poisoning the food. Some even suggested that this outbreak was a clear sign that the Republicans had attempted to assassinate Buchanan before he could take office. In truth, the disease was most likely a form of dysentery or Legionnaire's Disease caused by a burst sewage pipe polluting the hotel's water supply. It's not as sexy as presidential hopeful John Fremont trying to murder Buchanan with Shitting Plague, but that's the nature of truth: It's rarely more glamorous than an elderly politician destroying his chamber pots after drinking poorly treated hotel water. 3.Phossy Jaw Destroyed Faces In The 1800s Working in an Industrial-Revolution-era factory was many things, a laugh riot not being one of them. If you weren't being scalped by machinery or scavenging in the sewers for valuable trash, you were in a matchstick factory suffering from "phossy jaw" -- a whimsically-named condition wherein your jaw spent most of its time trying to grow itself off your goddamn face like it was vying for independence. Did you notice that we said "matchstick factory," not "face-melting chemical plant"? Back in those days, matches were made by dipping pieces of wood into a chemical called white phosphorous. Although the white phosphorous allowed the matches of the time to burn more strongly than their predecessors, the dipping vats produced insane levels of toxic fumes. The workers who dipped the matches began suffering from chronic toothache, followed by their jaws exploding into discharge-spewing, abscess-covered masses of glowing bone. If the diagnosis wasn't terminal, the patient would be forced to have their jaw amputated in order to save their life. That's because biology is an utter bitch. At this moment, your body is releasing chemicals that break down unhealthy bone and replace it with new bone. In healthy people, it's a seamless process. In people who spend their days vaping phosphorous, however, the chemical disrupts the body's ability to break down unhealthy bone. As a result, the body keeps piling new jawbone on top of infected jawbone, and you can't quit, because Social Security won't be invented for another century. As silly as it might sound, phossy jaw is an accurate name -- you literally get a jaw full of phossy. We'd like to say that when this condition first emerged, factories stopped using white phosphorous and switched over to the safer, costlier red phosphorous. And we could say that, if we felt like building a house of lies. You see, while phossy jaw was first identified in 1858, it wasn't until 1906 that a ban on white-phosphorous-made matches was finally instated. That's nearly 50 years of people's jawbones mutating for a specific, well-known reason, and nobody doing anything about it for fear of offending an important industry. Sounds kind of familiar, doesn't it? 2. The Plague Of Athens Was So Bad That The Spartans Refused To Invade Of all the reasons Rio 2016 might turn out to be a shitshow (literally), the Zika virus is the one that we should be most worried about. That said, we've got some historical perspective for you. Zika is a virological nothingness compared to the Plague of Athens, a raging pestilence that devastated the city-state during the early years of the Olympic Games, turning everyone it encountered into a messy puddle of blood, sweat, and poop. It's only thanks to one ballsy historian called Thucydides that we know how the disease operated. In its early stage, victims suffered from "violent heats in the head" and "redness and inflammation in the eyes," swiftly followed by their throat and tongue erupting into a Shining-esque torrent of blood. If there was any life left in the patient, that was swiftly ejected along with the contents of their bowels. It was such a horrendous fluid-fest that during the Siege of Athens, the Spartans turned and fled when they saw all the pyres of infected bodies. That's right: The Spartans, stars of the historical docudrama 300 and legendary celebrators of violence and bloodshed, took one look at the plague-ridden citizens of Athens and said, "We'll come back when you guys are feeling better." It's estimated that anywhere between one-third and two-thirds of the city were wiped out over a half-decade, before the plague up and vanished into the night. Oh, that's right; we don't know what the plague was, hence the word "vanished." And the list of suspects isn't what you'd call great. There's typhoid, which matches the reported symptoms, but couldn't have caused a sudden apocalypse-level outbreak because it was already killing people in Ancient Greece. Another possibility was typhus, which acts quickly but doesn't cause the reported symptoms, and Ebola, which fits perfectly ... except for the fact that this would mean after devastating Athens, Ebola went underground for two millennia before resurfacing for its first official recording in Zaire in 1976. But don't worry, this Pandemic Mystery is probably on the verge of being solved, as we've begun digging up the ancient victims' mass graves, because it seems no one in the scientific community watched Outbreak. 1."Glass Delusion" Convinced People They Were Made Of Glass It's hard to imagine that anyone in the Middle Ages had time for hobbies, what with the never-ending carnival of misery, plague, inquisitions, beheadings, and warfare. However, they found a way with "glass delusion" -- a psychological disorder that became de rigueur across Europe for everyone from royalty to the common-law mud harvesters of the time. The condition was simple to diagnose. Sufferers were convinced that they were literally made of glass, and that any movement, no matter how slight, would shatter them into a million pieces. It also came and went in moods. In one moment, someone could be walking and talking and carrying perfectly fine, and the next be rendered unable to move from their bed for fear that they might break. If you want to experience this for yourself, you can either drink to the point where you collapse on the floor and the slightest movement will make you scream the contents of your stomach into a perfectly vertical geyser, or you can simply pretend you have the disease until you really have it. See, that's the weirdest thing about glass delusion: how it spread. One of the first sufferers was King Charles VI of France in the 1400s, although how or why he became consumed by the idea that he was nothing more than a blown glass sculpture of a man and/or the villain from an M. Night Shyamalan movie has been lost to history. Either way, his affliction triggered a massive outbreak soon afterwards, and it's thought that this was the result of the populace imitating his illness because of celebrity culture. Unfortunately, the nature of pathology being what it is, you can only pretend to act a certain way for so long until you actually are that way, so anyone copying the king's bizarre condition might have eventually found themselves afflicted with it for realsies. It was the 15th-Century equivalent of everyone getting the "Rachel" from Friends, only to discover that all that Friends exposure had turned them into terrible people. Source