During the Galactic War between the Galactic Republic and the reconstituted Sith Empire, the exiled scientist Sannus Lorrick caused an outbreak of the rakghoul plague in the Tion Hegemony. A number of worlds were overtaken by the plague before quarantine measures were instituted, and the planet Kaon was the fifth world to be overtaken by rakghouls. The plague was eventually tracked back to Lorrick's laboratory on Ord Mantell, where he was killed, but not before the passenger liner Stardream was infected by Lorrick's efforts; the liner crashed on Tatooine and caused a galaxy-wide crisis.
The outbreak represents the events of the Flashpoint: Kaon Under Siege in Star Wars: The Old Republic. This flashpoint is available to both Empire and Republic factions so it is not known which faction is canonically responsible for sending the strike team. The composition of the strike team does not alter events, though it is assumed that an Imperial strike team chooses the dark side option to kill Melarra at the end of the battle, while a Republic strike team chooses to release her.