Nanovirus A nanovirus , also known as a nanokiller , was a selective virus designed to kill only an individual or specific groups of people that it had been developed to , without harming other undesired individuals . Nanoviruses targeting specific beings or groups of beings were notoriously difficult to produce due to the need of identifying an entire genome , or else the virus would not attack the target . Routine natural mutation , interbreeding , and genetic engineering would make an individual immune to the virus ' s effects . This weakness could be skirted by having the virus target a specific , unchanging gene sequence that would make its target or targets stand out from the larger population such as the one used to increase the rate of aging within clone troopers . More dangerously , a nanovirus could be keyed less specifically in order to kill subjects of an entire race , such as humans , indiscriminately . History . One example of a nanovirus was the FG36 virus , under development at the start of the Clone Wars by the Separatist - aligned Doctor Ovolot Qail Uthan . FG36 was specifically engineered to target the Fett genome present in the Grand Army of the Republic ' s clone troopers . Uthan and her scientific team were sent to a secret lab on the remote planet of Qiilura to carry out their work . However , before development of the virus could be completed , Uthan was captured by the clone commandos of Omega Squad and brought into Republic custody . The lab was destroyed and development of the virus presumably halted ; Supreme Chancellor Palpatine , however , kept the unfinished nanovirus and Uthan was held on Coruscant as part of a back - up plan for stopping the clone troopers , should they ever turned on him . After the formation of the Galactic Empire , Palpatine used FG36 on Uthan ' s home planet of Gibad , killing all sentient life on the planet . Because of this and the danger the virus continued to pose , Uthan — having been rescued from her incarceration at the Valorum Center by Mandalorian Kal Skirata and his associates — developed an antigen to immunize against FG36 . The completed antigen was spread first to Skirata ' s clan and across Mandalore , and then to the Jedi community of Master Djinn Altis . A variant of the nanovirus was used on Mon Mothma during negotiations with Furgan , the ambassador for the Carida n system . He brought his own drinks with the real drink on one hip , the nanovirus on the other . The nanovirus was made to kill her slowly , and make it look as if the Rebellion was dying , being bureaucratized by the New Republic . It did not kill her , because Carida lost control over Terpfen , who immediately told what happened to the New Republic on the toxin . Then , Cilghal , a Jedi Learner at that time , healed her by removing the nanovirus particles from her . A variant of the FG36 virus was later developed by the Imperial Remnant ' s Council of Moffs during the time of the Second Galactic Civil War . It was first used during the Battle of Roche , where it specifically targeted the Verpine soldier caste , while leaving other Verpine unharmed . Soon after , the virus was developed to target the Hapan Royal House , and another strain to target Boba Fett and any other member of the Fett genome was deployed on Mandalore . . However , the effectiveness of the Mandalore - deployed nanovirus was questionable , due to the cure to the baseline virus that had been spread across the world decades prior , in the weeks following the Clone Wars . Despite doubts as to its effectiveness , by 45 ABY , the nanovirus had prevented Fett ' s offspring from returning to Mandalore , specifically Mirta Gev , who worked to find a cure to the nanovirus . In her efforts to find a cure , she allied her Mandalorian soldiers to the Columi brothers , Craitheus and Marvid Qreph who agreed to help develop a cure . However , the Qrephs either refused or were unable to develop a cure , leaving the offspring of Fett to find another way to cure the nanovirus and be able to return to Mandalore .