Immunity

Immunity is the ability to completely or highly resilient to a specific chemical or weapon.

Vampires

 * Gun - A gun with regular bullets won't do anything but "tickle" a Vampire. A gun with a wooden bullet will kill the vampire.
 * Knife - A knife won't injure a Vampire either.
 * Most STD's - Vampires can't contract many STD's except for Hepatitis D.
 * Cancer - As Vampires are "undead" cancer will not effect them.

Maenad

 * Gun - Gun's won't kill a Maenad. As seen with Lafayette Reynolds when he shot Maryann Forester she just blocked it and it hit Carl.
 * Any Human Conventional Weapon.
 * Any BioWeapon Maenad's have passed the ability to die, and the only way they can die is if they believe they are dying for the God Who Comes.