The material below is Open Game Content from a 3PP Source
Your touch can infect and drain vitality from undead.
Benefit: Once per day, whenever you make a successful touch attack against an undead foe, you may regain 1d8 hit points, and the undead must immediately make a saving throw versus the vivification virus with a DC equal to 13 + your character level . If the target fails the saving throw, he is immediately afflicted with the vivification virus. If the undead is already infected, it is instead affected by the effect of the disease.