It took only a moment for Lucas to process what he just heard and it was like a nuke went off inside his head as he stared at Imani without blinking. She already explained what the vampire cell killing drug does and since that was in the Sirizan virus, they now knew exactly what was killing the werewolves.
The healing gene was basically concentrated amounts of vampire blood and since a werewolf's body couldn't handle that, they died. They didn't come back as vampires because of the vampire cell killing drug that was also in the virus.
".... Jesus," he muttered, taking in a deep breath as he removed his hands from her arms and placed them on his face. He couldn't believe it and believed it at the same time and he wished he had been the one to kill Tyrone. He also hoped Willard had killed Immith.