[Name] Phazon Madness [Source] Metroid Prime [Symptoms] 
A virus transmitted by being in close proximity to Phazon. The victim's mind is warped so they can no longer tell friend from foe, and exist only to destroy. Phazon Madness is extremely contagious, and it later develops into Phazon Fever, wherein the victim gains an obsessive compulsive disorder regarding Phazon. Infected victims can utilize Phazon as a weapon and normally can only be killed by Phazon itself.