The Kharaa Bacterium is the name given to a disease that has been central to the combined Subnautica and Natural Selection universe.
Background
Architects
The Architects are the first known species to have encountered Kharaa, doing so at least ~1,000 years prior to 2181. Due to a failure of quarantine procedures, Kharaa spread into the Architect Core Worlds where it ravaged the population, with a confirmed death toll of 143 billion individuals.
In their attempts to find a cure, the Architects set up research outposts on planets throughout the galaxy. One such planet was 4546B, where promising research on a species designated the "Sea Emperor" identified a unique enzyme dubbed Enzyme 42, which was able to temporarily neutralize Kharaa in infected organisms. The Architects captured a Sea Emperor specimen along with its clutch of eggs and housed them in an aquarium; however, the adult Sea Emperor, being of an old age, was only capable of producing a weak form of Enzyme 42. It was thought that a juvenile specimen's enzyme may be able to completely purge Kharaa from the system.
To expedite the hatching of the Sea Emperor Leviathan's eggs, the Architect researcher Al-An acquired a Sea Dragon Leviathan egg to study the hatching mechanism. This egg was housed in the Disease Research Facility, resulting in the parent Sea Dragon attacking the facility and destroying it, at the cost of its own life. With the facility's destruction, its quarantine systems failed, and Kharaa was released into 4546B's waters. It spread and seemingly managed to infect all Architects present on the planet, who had their physical bodies destroyed and consciousnesses interred in digital sanctuaries.
With 4546B infected, planetary lockdown was enacted and the world cut off from the outside for around 1,000 years until the arrival of the Alterran ship, the Aurora, in the year 2181.
Humanity
Humanity first encountered Kharaa in the year 2181, when the Aurora survivor Ryley Robinson became infected by Kharaa's pathogenic form on the ocean planet 4546B. After Ryley released five Sea Emperor Leviathan juveniles into 4546B's oceans, he was cured of the disease and Kharaa was purged from the planet's waters.
Later, around 2183, an Alterran research expedition to 4546B uncovered a surviving strain of Kharaa in the deceased body of a leviathan that had become frozen solid at an unspecified time within the past 1,000 years. This strain was markedly different from the infectious form previously identified, having evolved into an insular strain with low potential for infection that slowly fed on the frozen leviathan's body. This strain was eliminated by Robin Ayou, who, following her sister's wishes, did not want the disease to fall into Alterra's hands.
Some time after the year 2183, a vastly different form of Kharaa was unearthed in a Mongolian mining facility named Neo-Caligo in the Ariadne Arm, operated by the company Apex Industries. The first recorded outbreak took place in a colony on the moon Freya IV. This form of Kharaa functions entirely differently from the initially encountered strains and spreads by forming advanced biofilms and mutating lifeforms it encounters into aggressive disease-spreading organisms.
Up to around the year 2200, humanity fought against Kharaa's spread, the events of which are seen in the Natural Selection series.
Databank Entry
Mantis - "Kharaa memories"
Kharaa. Yes. There were rumors Alterra and the TSF let it spread, so they could take over the Steppes. I don't know about that. But it it hit us so fast. Did it really ride on the outside of our ships? Or do the spores just...fly through space?
We called it kharaal, the curse. Not all of us spoke Mongolian, but we knew that word. It started with the carpet, toiruulga. Then monsters would grow. If you didn't have nanos, they would grow in you too. We had to leave everything.
Now this. The virus that fills this ocean, and fills our blood. We thought it was kharaa at first, but it's not a bacterium. How can a virus cross between alien species? Nahema tries to explain it to me. I cannot understand how such a gifted young woman carries such anger. Or why she seeks me out.
[metadata author = Zygimantis "Mantis" Tarvydas]
Source: Found on a platform in the Shallows east of the Digestion Angel Comb
Trivia
- The Chinese translation of Kharaa Bacterium is "卡拉病毒" (which means Kharaa Virus). Due to the differences between virus and bacterium, this translation is a mistake that has been circulating in the Chinese community.
