Un Ww prend +50% dégâts de poison, et un Vampire +50% dégâts de feu, ce qui reste un malus non négligeable.
Source :
Lycanthropy
Receive +50% poison damage regardless of whether or not the player is transformed.
Lycanthropy increases in rank by killing in werewolf form.
Vampirism
Receive +50% damage from fire sources.
Breaks down into 4 stages of hunger depending on the last time the player has fed.
Stage 1: 30 minutes; no additional effects.
Stage 2: 60 minutes; -25% health regeneration, -20% mana cost for vampire skills.
Stage 3: 90 minutes; -50% health regeneration, -40% mana cost for vampire skills.
Stage 4: 120 minutes; -75% health regeneration, -60% mana cost for vampire skills.
http://eldersouls.com/elder-scrolls-online/skills