->''"Her condition was a case of ''terminal moe'', a dangerous illness which crops up in anime whenever they want to make a character more sympathetic through illness but don't want to actually attribute a real illness to them."''
-->-- ''[[http://www.fanfiction.net/u/1263379/gabriel_blessing Gabriel Blessing]] comment on the real illness behind [[{{Sekirei}} Chiho]]'s condition''

Common ailment found on the SoapOpera. It is notoriously difficult to diagnose, and often exhibits vague symptoms. Often fatal, but victim can linger on for a long, long time. Sometimes results in a lengthy coma which, upon the victim's recovery, may also manifest a radical change in appearance (see: TheOtherDarrin).

Creator/JMichaelStraczynski has mentioned one riff on this, in which a soap opera writer supposedly put a character into a coma with very specific and carefully-researched symptoms, for a plot that was only supposed to last a couple of episodes... and then realized that if the character's recovery was delayed, he could continue to crank out script after script without ever needing to worry about a pink slip, since nobody else on the writing team knew enough about the disease to write the character's recovery. The actress didn't mind either, since she got a paycheck day after day for a few minutes' lying absolutely still in bed. The producers were somewhat less than pleased at this.[[note]]Rumor has it that a couple of years later, the same writer called the producers asking if they needed his services again; he was told that the producers were still in a coma.[[/note]]

The anime trope of the IllGirl suffers from the same plague of vague. See its page for the full story but the gist of it is the same; some kind of frailty to gain sympathy.

A common mutation anywhere is the IncurableCoughOfDeath; a terminal illness with no symptoms of any kind besides coughing. More likely than not evolved from VictorianNovelDisease. The character may insist the illness is DefinitelyJustACold. Not to be confused with SoapOperaRapidAgingSyndrome, which isn't actually a disease so much as a PlotHole that sucks up babies and children and spits out [[SheIsAllGrownUp teenagers or even adults]].
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!!Examples:

[[foldercontrol]]

[[folder:Anime & Manga]]
* At one point in ''Manga/RanmaOneHalf'', Master Happosai suffers from a case of this. Unfortunately, he gets better. Also, the teacher Hinako Ninomiya had a case when she was young. She gets better as well.
* Sahana from ''Sundome'', with her nosebleeds, dizzy spell and [[IncurableCoughOfDeath bloody coughs]]. [[spoiler: In the end, it gets her, and there is nothing that can be done. Hideo does his best to make her last days happy. He succeeds with that.]]
* In ''Anime/TheBorrowerArrietty'', the male protagonist Sho has a heart condition ever since he was a child. Just a short period of physical activity can cause him pain.
* ''Anime/VariableGeo'': Satomi's kid brother, Daisuke, suffers from an unspecified medical condition that keeps him bedridden with a hacking cough and, occasionally, seizures. The costs of his treatments are expensive, [[PerpetualPoverty even with Satomi working two jobs.]] Which is why she originally wanted to enter the VG tournament in hopes of winning the prize money and real estate.
* In VisualNovel/{{Clannad}}, Nagisa suffers from an undefined disease which prevents her from attending school from time to time. [[spoiler:Her daughter Ushio gets the same undefined condition. In both cases, it turns out to be fatal.]]
** [[spoiler:[[SubvertedTrope Or at least until the ]] ResetButton [[SubvertedTrope is used in the final episode/"true ending" of the game.]]]]
* MadScientist Ghinias Sakhalin in ''Anime/MobileSuitGundamThe08thMSTeam'' has some sort of disease that he has to take medication every day for. It mostly looks like paranoid schizophrenia, but he does have some poorly defined physical symptoms as well. The symptoms seem to fit Wilson's Disease, a genetic disorder that prevents the body from metabolizing copper properly whose most common symptoms are brain damage that often presents with schizophrenia-like symptoms and liver disease.
* Trisha from ''Anime/FullmetalAlchemist'' died of such a disease. It's never stated what it was but fans consider it either stress-related or cancer. Averted in the manga, where it's said she had a disease that was going around.
* In ''Anime/MyNeighborTotoro'', the disease that Satsuki and Mei's mother has is never revealed, though it is [[WordOfDante believed by many fans]] to be tuberculosis.
* Similarly Tsukimi's deceased mother in ''Manga/PrincessJellyfish'' had a vague, deteriorating disease that apparently lasted a few years. Eventually she was hospitalized and died.
* ''Franchise/KagerouProject'': Haruka Kokonose ([[spoiler:Konoha's former self]]) has a rather ambiguous illness (although a shot in the ''Konoha's State Of the World'' PV seems to imply it's a heart condition) that lands him in hospital for weeks, and prevents him from participating in physical activities. [[spoiler:He dies at 17, after a few-months-long {{Timeskip}} after his introduction. However, since it was triggered by the BigBad on purpose, we'll never know how long he would have lasted on his own]].
* Kousei's mother in ''Manga/YourLieInApril'' died of an illness that left her wheelchair bound. [[spoiler:Kaori suffers from a similar disease that caused her to gradually lose the ability to play the violin or walk over the series. She dies of complications during surgery instead of the illness itself, though it was considered terminal]].
* In ''Manga/BokuNoHatsukoiWoKimiNiSasagu'', Takuma suffers from a heart condition that doesn't allow him to do any physical effort nor getting him too excited, as it causes him to faint. Other characters, like his childhood friend Teru and [[spoiler:Kou and Ritsu's father]], suffer it too.
* ''LegendOfTheGalacticHeroes'' [[spoiler:Reinhard dies of a completely straight example of this. Which comes off as a little strange since he's in his early twenties and living in a future a couple of thousand years ahead of the present day in which one would think medical technology would be advanced enough to at least identify it. Especially considering they're dealing with the emperor of the entire galaxy. Rebuisky dies of a more explicit brain tumour]].
* ''Manga/IllBoyIllGirl'' has a disease that has no particular ill effects outside of (possibly) coughing up black blood. The only huge effect it has is that names, faces, and practically anything that relates to a person is, in the eyes of the infected, blotted out or obscured. The only faces they ''can'' see are other people who are infected.
* Subverted by Hayate in ''Anime/MagicalGirlLyricalNanohaAs''. While her doctors have no clue as to why the paralysis in her legs is slowly moving up her body, the Wolkenritter and the audience are all too aware that it's being caused by the [[ArtifactOfDeath Book of Darkness]].

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[[folder:Comic Books]]
* Miss Grundy gets diagnosed with this in the first issue of ''ComicBook/LifeWithArchieTheMarriedLife'', and dies a few issues later as a result.
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[[folder:Fan Works]]
* In ''Fanfic/TravelsOfTheTrifecta'', Paul and Reggie's mother died of an unnamed terminal illness. [[spoiler: Paul learns that he has the same mysterious illness because it's genetic. It seems to have periodic coughing up blood, physical frailty and weakened immune system as general symptoms]] but it is not stated to be any real-life disease. Given that Pokemon has animals that don't exist in real life, the Pokemon world having its own genetic diseases isn't too unusual.
* In Webcomic/KillLaKillAU, while they are not terminal, although severe, some of the illnesses Ryuuko suffers from are not named and neither are her symptoms described, however, she is often seen attached to machines and intravenous drips. This is played with in ''Room 002108'', chapter 9, where it is stated by an American doctor that she has some unknown illness, the which turned into septicemia, which implies it was some kind of bacterial infection, causing her blood to poison her, the which almost killed her or should have.
* ''Gensokyo20XX'' series:
** Keine and, besides the fact it was terminal, the symptoms were only described as "pneumonia and lumps in her lungs".
** The second time is with Reimu's mother, Reiko, and she passed away of a long term illness, although this is justified in that they didn't know what she has and neither could they diagnose it but it is implied to have had something to do the radioactive fallout.
** Ran and, apparently, it's chronic but not terminal, however, it does leave her with bouts paralysis (the authoress describes it as being similar to multiple sclerosis). Likewise, the same occurred with Yume Ni and her chronic illness, the which she's passed away from.
** Reimu and frequent illness (the which are treated with intravenous therapy) and Renko's illness which caused her a degree of brain damage, leading to some degree of blindness and memory loss.
* From one Anime/KillLaKill fic, titled ''[[https://www.fanfiction.net/s/11037352/1/%E9%A3%9B%E9%B3%A5-Asuka Asuka]]'', we have this with either Satsuki or Ryuuko (it's never made clear which), who was diagnosed with something that is described to be "chronic sans cure" and [[spoiler: she dies of her illness in the end]]
* The illness an implied to be SecretlyDying Ryuuko has in ''Raindrops'' is not named, yet the symptoms are vaguely described, although it is severe and does result in her death. Averted in the case of Satsuki in ''Sunshine'', who explains that she has leukemia and was LivingOnBorrowedTime.
** Similarly, in ''As the Wind Blows'', we have this with Shiro and his illness. However, given the fact that he's elderly, it's likely age-related.
* This is averted in the fanfic ''[[http://archiveofourown.org/works/1854724?view_adult=true Endless Numbered Days]]'' by janewithawhy with Satsuki's illness being [[spoiler: lung cancer, the which progresses to terminal]].
* Naruto's illness in ''Fanfic/AccidentalCompanions'' isn't named, however, he has been ill with it for a long time and is implied to have [[spoiler: died of it]]
* Played with. While her sister, Ryuuko's illness was implied here and there in ''Through Thick and Thin'' as being cancer (i.e, her being a special diet and being treated with chemotherapy) an, in a prequel, outright stated to be "Non-Hodgekin's Lymphoma", Satsuki's illness isn't too spelled out, however, she was being treated at home on medication, before being hospitalized for surgeries, making her's more vague.
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[[folder:Film]]
* ''Film/DancerInTheDark'', a drama and musical film, focuses on a female protagonist who has a genetic disease that causes her vision to weaken as she gets older. Early on in the film, she is already legally blind, and this serves as a big element of the plot.
* Parodied in ''Film/TheLivingWake'' where the self-deluded main character is certain he will die of "a vague and grave disease" despite clearly being in perfect health. [[spoiler:He ends the wake by stepping ceremoniously into a coffin where he instantly dies.]]
* ''Film/LoveStory'' has been accused of playing this straight. (see Magazines, below.)
* In ''Film/TheSignal2014'' Nic walks with two crutches because of an unnamed wasting disease which he says will eventually put him in a wheelchair.

[[/folder]]

[[folder:Literature]]
* ''Literature/TheInfernalDevices'': [[spoiler: Jem's. It was caused by a demon drug that was used to torture him and his parents when he was younger. There is no known cure for it, and he has to keep taking a specific drug to keep on fighting - as Brother Enoch says, taking the drug means a slow death, but keeping him off the drug would mean a quick one.]]
* Appears as Drummant's gift in ''Literature/AnnalsOfTheWesternShore''. {{Justified}} because that seems to be the whole ''point'' of the Drum gift, which is called "wasting". The victim just gets weaker and weaker for no apparent reason until they eventually die, which takes about a year. [[spoiler:This is how Melle, Orrec's mother, dies.]]
* In ''Literature/VampireAcademy'', Viktor Dashkov is ill with Sandovsky's Syndrome, a Moroi-exclusive disease, which is slowly killing him.
* In the ''Literature/HyperionCantos'', Matrin Silenus mentions that when he wrote his ''[[CashCowFranchise Dying Earth]]'' books, book 3 introduced a telepathic child dying from some strange disease. He went into a drinking celebration once he was allowed to let her die in book 9.
* In ''[[{{Literature/Foundation}} Foundation and Empire]]'', Emperor Cleon II suffers from some painful and unknown disease which no one can cure.
* Doki in the 56th ''Literature/MadgieWhatDidYouDo'' story. What she has is something she was diagnosed with over eighteen months prior and no doctor could tell if it was terminal or not. Likewise, in the previous story, she was terminally ill and was suffering kidney failure, thus being in what would be considered hospice care, however, what she had wasn't stated but she does die from it.
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[[folder:Live Action TV]]
* ''Series/BuffyTheVampireSlayer'': In the comics, it was retroactively explained that Drusilla was tortured by an "Inquisitor" while in Prague, including the use of a magic torture chair, leaving her in a frail condition. Spike initially hopes the Hellmouth will restore her, but later learns that the blood of her sire (Angel) can cure her affliction.
* Although Alzheimer's Disease, which normally takes years and years to build up, not only progressed ten times faster than real life, but then slew Mike Baldwin in a matter of mere ''months'' in ''Series/CoronationStreet''
* Appears in, of all things, the profiler procedural ''Series/CriminalMinds''. In an early episode, in a very dramatic scene, Hotch's son has had to go to the hospital to get "some tests" done and it turns out he has "a condition". This is [[BigLippedAlligatorMoment promptly never mentioned again]].
* The protagonist in ''Series/OneLiterOfTears'' suffers from a harsher and much rarer kind of this.
* The first episode of ''MrShow'' opens with Ronnie Dobbs doing a PSA for his disease "Entitilitus." He notes that no one knows where it comes from or what it is, but "entitilitus kills." Toward the end of the episode, Terry sells the rights to make a {{Biopic}} of Ronnie [[spoiler:after he dies]]. In the film, the Ronnie reveals to Terry that he suffers from entitilitus [[spoiler: then dies in his arms]].
* This is essentially the fate of [[spoiler: The Mother]] in ''Series/HowIMetYourMother''. The disease is fatal, and that's pretty much all we know about it.
* [[spoiler:Shuichi Kitaoka/Kamen Rider Zolda]] from ''Series/KamenRiderRyuki'' is revealed to have one of those, it's actually his main ulterior reason for entering the Rider Battle. Very vaguely described and with no apparent symptoms other than the occasional fainting and easily acted spasms, but it's terminal (he had a few months left at best at some point) and incurable. The novel reportedly had him have Alzheimer's instead, which is odd since he looked to be barely in his [=30s=] in the show.
* ''Series/{{Vikings}}'': In season 3, Ragnar's health slowly starts to deteriorate while besieging Paris. Whether it's from some illness, an accumulation of battle wounds, or a combination of the two, it's never revealed. When hey gets back to Kattegat, he's bedridden and everyone assumes that he's dying. However, he eventually makes a slow and equally unexplained recovery in season 4.
[[/folder]]

[[folder:Magazines]]
* Magazine/{{MAD}} referred to this as "Old Movie Disease" in their parody of the movie ''Film/LoveStory'', along with the claim that it makes you more attractive so you can die a beautiful death.
[[/folder]]

[[folder:Video Games]]
* In ''VideoGame/EternalSonata'', if you're able to use magic powers, it also means that you have vaguely defined illness that is eventually fatal, though it's hard to say exactly when.
* Any Creator/KeyVisualArts game will have at least one IllGirl that suffers from this, with the exception of ''VisualNovel/{{Planetarian}}'' where the disease is [[spoiler:low battery power with no way to recharge]]. Thus one of the alternate titles for this page, "Key AIDS".
[[/folder]]

[[folder:Web Original]]
* Inverted in the ''WebOriginal/{{Paradise}}'' setting, in which humans are randomly, permanently Changed into {{Funny Animal}}s by causes unknown. The change is InvisibleToNormals, to whom the Changed will still appear to be his old human self. In order to prevent Changed from being injured by medical practitioners because of physiological differences the medics can't see, the Changed invented a fictitious ''real-world'' disease—-"Sleeping Sickness (Ivory Coast Variant)"-—and issued medical alert bracelets for it so that a Changed or Known physician could be alerted at need.
* From Wiki/{{Killerbunnies}}, we have Anwen's condition and not too much information is known about it besides the fact that will eventually kill her, along with it being progressive.
* Creator/LittleKuriboh parodied this in his [[https://www.youtube.com/watch?v=1bvGhzLQbCY Patreon video]]. He was diagnosed with a specific and chronic, but not fatal, colon condition, and Martin and his wife [[{{Melodrama}} wept and wailed about it]].
[[/folder]]

[[folder:Western Animation]]
* Mocked (as with many other soap opera tropes) in the ''[[SoapWithinAShow All My Circuits]]'' segments of ''WesternAnimation/{{Futurama}}''.
* Also mocked in an episode of ''WesternAnimation/AlvinAndTheChipmunks''. Theodore gets hooked on a soap opera where one of the characters has a disease called Zomboid Rigadosis. Alvin and Simon try to convince him it isn't real, but they all panic when Dave appears to have become stiff and motionless, and try to find a way to cure him. It was actually a wax statue.
* In "Magic Gift of the Snowman", Emery has a disease that can be fatal, and one of the symptoms is paraplegia. Modern medicine can't do much to treat it, but people who have the disease can fully recover if they want to recover enough. When Emery recovers, the symptoms disappear overnight, including her paraplegia.
[[/folder]]
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