Werewolf

A werewolf is a person afflicted a very special virus that caused them to experience periodic temporary metamorphoses into an animalistic state.

The werewolf virus is a rare strain of rabies that mutated into a non-fatal form but kept some of the most ferocious side-effects. Although this strain of rabies doesn't kill a person, it does take them over. In normal rabies, the virus tunnels through the nerves directly to the brain, avoiding the immune system. However, this is not the case with the werewolf rabies virus. Werewolves have the virus in almost every cell of their body.

A biochemical malady caused by the werewolf virus is a slow build-up of toxins in the werewolf's body that every two or three months reaches a critical level and forces major endocrine system changes that initiate a temporary transformation. During this transformed state, the werewolf exhibits some of the usual symptoms of rabies; such as anxiety, hallucinations, delirium. Those symptoms together with a cerebral dysfunction and an insatiable hunger, induce a frenzy that causes the werewolf to behave like a rabid animal. A swelling of the adrenal glands causes a massive surge of adrenaline that gives them augmented strength and speed. In addition, the body-wide biochemical modifications induces a few physical changes as well. From head to toe, the body experiences a super-acceleration of hair growth in a matter of hours, giving the werewolf a very hirsute appearance. A highly increased metabolic rate allows this rapid hair growth and is also responsible for the increased hunger.

Along with the hair growth, the skin tightens, making the nails and teeth appear to grow. The tightening of the skin added with a distortion of the muscles of the face, causes the facial features to change, taking on an animalistic look. In addition, there is an inflammation of the sclera, making the whites of the eyes appear red. A particular alignment of the body's circadian rhythm causes the transformation to only occur at night and to end at dawn. The legend that werewolves turn during the full moon arose from the fact that that's simply when it's easiest to see them. When the transformed state is over, the only physical change that remains is the excess body hair; it must be shaved off. The physical exertion caused by these episodes of physical transformation will leave a werewolf exhausted and vulnerable.