Lycanthropy is a curse that causes the afflicted to transform into an animal at either the full or new moon, depending on the case, with supernatural strength and speed, and regeneration that makes them almost impossible to kill without silvered weapons. Forced transformations override conscious thought; some lycanthropes who embrace the condition learn to transform at-will, retaining their minds, though they still lose themselves when they change automatically. The curse can be inflicted by powerful magic-users or other beings, and carriers transmit it to people they bite or claw (if they survive, which is rare). A single lycanthrope is extremely dangerous, but fortunately, the condition is rare. You've hardly ever heard of more than one victim being found in the same place at the same time, which makes it unlikely that this wolf pack were werewolves.