Slow, subtle and extremely complex pathogen hidden inside the brain.

Plague Type:


Special Ability:

Neural Atrophy


Complete Parasite (Normal or higher) or $0.99USD

Release date:

May 23, 2012, Version 1.0

Core Stats:

Infectivity: 1 Severity: 1 Lethality: 0 Cure Requirement: 120% Mutation: 0.5

Base Cross Country Transmission:

Air: 1 Sea: 1 Land: 1

Base Environmental Effectivity:

Wealthy: 0 Poor: 1 Urban: 1 Rural: 1 Hot: 0.1 Cold: 0.1 Humid: 1 Arid: 1

Special Attributes:

Takes much longer to translate Infectivity, Severity and Lethality changes in DNA to the world compared to most basic plague types; Infectivity increase speed: 0.05 (min 0.5) Severity increase speed: 0.04 (min 0.4) Lethality increase speed: 0.01 (min 0.1)


Slow, subtle and extremely complex pathogen hidden inside the brain - it is much harder to notice and cure. Disease takes longer to react to new evolutions. 


The unique trait that Prion has in Plague Inc is Neural Atrophy, which is like Genetic Hardening, slowing down cure research. Evolved traits will take longer to take effect, thus Prion will act slower than other pathogens.


Please see Prion Strategy Guides.


  • Devolving Neural Atrophy will cause the cure effort to speed up, if there is any.
  • Real life prions do not contain any DNA or RNA and can thus not evolve in the way typical pathogens like bacteria and viruses do. They are, effectively, only malfunctioning proteins (unlike viruses, since they have the entire set of DNA/RNA that fragments as it goes). Nonetheless, the game continues to use the DNA-evolution-motif for prions, even going so far as to show a prompt saying "Prion DNA detected". This is most likely an artistic liberty taken by the developer to not deviate the game-play too much from the other pathogens. Additionally, in real life, Prions cannot be cured, but to keep in balance with the game it is also vulnerable to the cure like the other diseases.
  • Prions in the real world are responsible for, or at very least in some way correlated with, a variety of neurodegenerative diseases such as Alzheimer's disease and the infamous Mad Cow disease. Depending on the type of prion, they can have an incubation time between anything of just a few weeks or over forty years.
  • Prion diseases are mostly known for affecting the brain since the prion protein-gene, a gene responsible for producing essential proteins, is especially active in the nervous system. Any misfolded proteins can thus easily spread in the brain and cause prion diseases. However, prions can just as well be found in other organs.
  • Kuru, a disease seemingly exclusive to the cannibalistic people of Papua New Guinea, is most likely a prion disease. Researches noted that women and children were especially susceptible to the disease. When prions as a possible pathogen were considered, the cause of this discrepancy became clear: While the men primarily ate the muscles of an infected person, women and children would eat the organs, including the pathogen-rich brain.
  • Prions may occur sporadically or have a very clear chance of inheritance. Currently, they are generally thought to be incurable, and at best their spread can be slowed down. However, this poor outlook is mostly due to the fact that prions are still a relatively new field to medical science, and is bound to change.

Stages of Evolution Edit

Standard Plague Types


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