History Main / BeneficialDisease

* Partial expression of Sickle Cell Anemia causes mild anemia, but also renders provides great resistance to malaria.

-->'''Doctor:''' Oh good ''no'', the slightest breeze could...

* From Generation 2 onward, the main ''{{Pokemon}}'' video games have had the Pokérus virus. If you're very, very lucky, a wild Pokémon you fight might just spread Pokérus to one of your Pokémon. With this condition, that Pokémon will gain twice as many effort points (effort values are a complex hidden stat-growth mechanic, look it up) when an enemy mon is defeated. Basically, it will save you time when trying to fine-tune your Pokémon's stats. It can be spread from inside the mon's PC storage box. Pokérus does, however, "cure" after so many hours of play, so exploit it while it lasts. It isn't even clear whether Pokérus causes any suffering. So never mind the VideoGameCrueltyPotential of mass temporary infection, trainer.

* Sickle-cell disease [[UnderStatement isn't exactly pleasant to have]], but individuals carrying the sickle-cell gene actually have an increaced resistance towards malaria.

* It's been speculated that being immune to one type of bacterium or virus means you can't be infected by the same virus that can cause a much more deadly disease. It's speculation, though.

* Sickle-cell disease [[Understatement isn't exactly pleasant to have]], but individuals carrying the sickle-cell gene actually have an increaced resistance towards malaria.

* Sickle-cell anemia, which makes your red blood cells wither and become less capable of carrying oxygen, also makes one immune to malaria.

* A certain kind of anemia makes one immune to malaria.

This trope has appeared many times on ''{{House}}''. One of the characters has a disease that protects him/her from another, more deadly disease. In some cases, the disease might be fatal but give the person extraordinary powers.

* As mentioned above, this trope has been used multiple times on ''{{House}}''.

* It's actually been heavily speculate that Sickle-Cell anemia could potentially protect against Malaria.

* Sickle Cell anemia actually helps against malaria, which spread through red blood cells.

Examples:

* From Generation 3 onward, the main ''{{Pokemon}}'' video games have had the Pokerus virus. If you're very, very lucky, a wild Pokémon you fight might just spread Pokérus to one of your Pokémon. With this condition, that Pokémon will gain twice as many effort points (effort values are a complex hidden stat-growth mechanic, look it up) when an enemy mon is defeated. Basically, it will save you time when trying to fine-tune your Pokémon's stats. It can be spread from inside the mon's PC storage box. Pokérus does, however, "cure" after so many hours of play, so exploit it while it lasts. It isn't even clear whether Pokérus causes any suffering. So never mind the VideoGameCrueltyPotential of mass temporary infection, trainer.
** "Pokérus" (the poké-virus) has actually existed since Generation 2. The chances of encountering it in the wild are about 1 in 23,000 (''three times'' as rare as a Shiny encounter), but since there's no visible indication that the wild Mon has it, most players don't actually know about it.

This trope has appeared many times on {{House}}. One of the characters has a disease that protects him/her from another more deadly disease. In some cases, the disease might be fatal but give the person extraordinary powers

This trope is related to diseases that can either be cured by a medical treatment, or the body's self defense mechanism can cure the disease. The characters may elect to not cure or prolong the infection to gain the maximum benefit from the disease. For immunity/superpowers arising from disabilities of a more permanent nature, (disabilities cause by genetic mutations, accidents, or general in-born traits) see DisabilityImmunity. For example sickle-cell anemia that arises because of a genetic mutation resulting in lowered life expectancy, but also provides a degree of immunity against malaria is NotAnExample of this trope. It is an example of DisabilityImmunity, since sickle cell anemia is permenant. OTH, Cowpox which is a disease that provides immunity to a much more deadlier disease called smallpox is a good example of this trope

Also related to OneCurseLimit

* [[TheSimpsons Bart Simpson]] is diagnosed with Butterfingeritis. Homer grumbles, "Why does Bart always get the ''good'' diseases?"

[[AC: {{Fiction}}:]]
* The science fiction novel ''The Skinner'' by Neal Asher is set on a DeathWorld that has this gigantic leech whose bite carries a virus with interesting properties, rendering "victims" super strong and nearly immortal and indestructible. Almost all animals on-planet are infected by it, as are most humans who live there. The real downside is that the evolutionary "purpose" is so predators can have permanent prey, and even if you can't die, it doesn't mean you can't feel pain/suffer a FateWorseThanDeath.

* There's the Harry Potter fanfic [[http://www.fanfiction.net/s/1399984/1/ Recnac Transfaerso]] where having cancer causes Harry to develop on-off superpowered magic.

* The JohnTravolta film ''{{Phenomenon}}'', wherein the main character develops hyperintelligence and even psychokinesis because of what is eventually discovered to be a fatal brain tumor.

* As mentioned above, this trope has been used multiple times on {{House}}
* In TerraNova, a flu infection provides the main character immunity from another infection that wipes the person's memory
* In an episode of {{Stargate SG1}}, the characters receive a number of armbands that bestow superpowers on the wearers. They work by infecting the wearer with a virus that causes the changes. Unfortunately this means that the armbands only work for as long as it takes the body to develop an immunity to the virus.
* ''LookAroundYou'' has a disease called "Cobbles," which causes the skin to take on the appearance of stone until the victim looks like a pile of rocks, but also grants the ability to fly. The scientist who discovered a cure for the disease, a sufferer himself, opted not to use it because he liked being able to fly so much.

* Several "evil" diseases in D&D provide growing bonuses at the cost of penalties in other areas, in effect becoming a DeadlyUpgrade. The fans were quick to notice that the prestige class cancer mage can adapt to diseases, hoarding bonuses while ignoring the penalties...
* In Warhammer, this is Nurgle's hat. Since he is a PlagueMaster god, his servants become ravaged with all sorts of plagues but the effects don't kill them. They look utterly disgusting but not a bit weaker for it; they are actually harder to kill because they don't need to worry about things like infected wounds. Also they FeelNoPain, and the diseases they spread can still be lethal to non-believers.

* From Generation 3 onward, the main {{Pokemon}} video games have had the Pokerus virus. If you're very, very lucky a wild Pokemon you fight might just spread Pokerus to one of your Pokemon. With this condition, that Pokemon will gain twice as many effort points (effort values are a complex hidden stat-growth mechanic, look it up) when an enemy mon is defeated. Basically, it will save you time when trying to fine-tune your Pokemon's stats. It can be spread from inside the mon's PC storage box. Pokerus does however "cure" after so many hours of play, so exploit it while it lasts. It isn't even clear if Pokerus causes any suffering. So never mind the VideoGameCrueltyPotential of mass temporary infection, trainer
** "Pokerus" (the poke-virus) has actually existed since Generation II. The chances of encountering it in the wild are about 1 in 23,000 (''three times'' as rare as a Shiny encounter), but since there's no visible indication that the wild Mon has it, most players don't actually know about it.
* TheElderScrolls has vampirism, in which the longer it goes untreated, the victim gains more vampiric characteristics.
* In DawnOfWar2Retribution the healing of chaos units is done through the powers of Nurgle, by the means of supernatural disease - Nurgle's Rot. The infected units get back to the fight as their senses get numbed to the pain and their wounds get sealed by cancerous growths.
* in ''TheElderScrolls'', particularly ''{{Morrowind}}'', the Corpus disease grants the infected immunity to all other diseases and even prevents them from aging. Too bad it also comes with a big serving of BodyHorror and a bad case of crazy, and is completely incurable unless you are the [[TheChosenOne Nerevarine]].

* Cowpox, a relatively harmless disease in humans, conveys immunity to the much more serious smallpox. This fact led to the discovery of the science of vaccination.