The Kawaga Virus was a synthetic alien virus developed from the venom sacs of the Kawagan lizard. The virus created a feedback loop in the minds of infected individuals, rendering them immobile and unable to think clearly. This resulted in a kind of comatose state in which the victim was essentially dead, but still fully aware of their surroundings. Czisch's father described it as “living death”.
Once infected, the virus would take only a few minutes to fully take hold of a human victim. Jack Harkness and Gwen Cooper were deliberately infected with the Kawaka Virus by Czisch's father, who blamed Torchwood for the death of his son. After discovering the black market traders who had sold the father the virus, Ianto Jones set out to find the antidote. (PROSE: Virus)