The vaccine is an anti-"t" reagent, which makes a first and only appearance in Resident Evil 3: Nemesis. After Mikhail sacrificed himself in an explosion with "the pursuer", it returned and fought Jill. She won the battle, but was infected by a tentacle of the creature before her victory. Carlos took Jill to the Clock Tower's chapel and left for the Raccoon General Hospital to search for a cure. After returning to the chapel, to cure Jill, Carlos can just talk to her, or use the Vaccine on her. After a short cutscene, the player takes control of Jill again.