Prion variant was the deadly pathogen engineered by Jonas Hodges of the Starkwood company before Day 7. It was an altered form of the Creutzfeldt-Jakob disease, and attacked the brain and nervous system causing dementia, physical deterioration, and eventually death. Starkwood engineered it to be lethal within a shorter period (one or two days). The original pathogen was native to the East Congo. An experimental treatment for the disease was theoretically possible using stem cells, but was never attempted. Additionally, Tony Almeida insinuated that he was in possession of a secret treatment or cure.
Before Day 7
A Sangalan man suffers from the prion infection
Sometime before Benjamin Juma took over Sangala during the events of Redemption, Hodges and Juma began infecting native Sangalans in remote areas with prion variant. They exhibited mental degredation, uncontrollable movements, and other symptoms. As rumors spread of the terrorism, Juma fire-bombed the areas to destroy all the evidence.
Eventually, the pathogen was engineered to Hodges' satisfaction. In exchange for assistance with his political agenda and an invasion of the White House, Juma offered to ship the completed prion variant experiment to Washington D.C.
Day 7
Juma's men shipped the prion variant container to the Port of Alexandria, and Hodges mercenaries retrieved the bio-weapon with help from Carl Gadsen and despite interference from Jack Bauer and Tony Almeida. During the capture of the weapons, Jack became the first person infected with the prions in the USA.
The lead Starkwood scientists Tom Chapman loaded the prion variant onto some Python missiles, and the rockets were loaded with RP-7 rocket fuel. Hodges then used the rockets to force President Allison Taylor to meet and accept his demands.
CDC official Ben Landry briefed Taylor and the Joint Chiefs of Staff about the weapon. Also, Sunny Macer explained to Jack Bauer that a treatment for the prions was theoretically possible: stem cells from a compatible family member could be used to save his life (in his case, daughter Kim Bauer). But the likelihood of success was completely unknown.
Canister of the prion variant pathogen
Within a few hours, Tony Almeida exploded some of the RP-7 fuel using C4 charges, and the extreme heat of the inferno wiped out the prion particles in the rockets. One container of the prion variant was smuggled out by Robert Galvez for Tony Almeida, however, and remained a threat despite the capture of the Starkwood compound.
When Jack Bauer confronted Tony about his allegiance, he began to show symptoms of the prion infection again, but Tony had taken his syringe pack. Without being able to administer the dose of anti-seizure medicine, Jack collapses while Tony calls some paramedics to treat him giving him enough time to escape the scene.