Bad Brain Syndrome

There is no disease in the wasteland that carries the same weight of dread as Bad Brain Syndrome. Not because it kills; plenty of diseases kill. Because it transforms. The person you knew yesterday, the one who watched your back and shared your fire, becomes the thing that tears settlements apart from the inside. And by the time anyone realizes what is happening, the person they were is already gone.
  Bad Brain begins with contaminated blood. Raider biofluids carry a corrupted strain of Infection that, once introduced through open wounds or unprotected contact with Raider remains, begins rewriting the host's neural tissue. The corrupted Infection targets the aggression and paranoia centers of the brain, breaking down the structures that keep a person recognizably themselves. Early symptoms present within hours: a low headache that will not ease, a sharpened irritability that spills into unprovoked outbursts. The afflicted may not even realize what is happening to them. Their friends might write it off as a bad day. It is not a bad day. It is the beginning of the end.
  As the disease deepens, the signs become impossible to ignore. Tremors and confusion set in alongside auditory hallucinations. Short-term memory fractures. The Infection's activity becomes visible through pulsating veins and a faint red discoloration around the temples and eyes. Language deteriorates from full sentences to fragments to primal noises. Motor control degenerates even as bursts of strength and aggression increase. The host becomes violent, hyperfocused on nearby movement and sound, losing the ability to distinguish between friend and threat. By the final stage, rational thought collapses entirely. The individual is functionally indistinguishable from a Raider, overtaken by a primal, Infection-driven rage. The body continues as a vessel for corrupted Infection long after the person inside has ceased to exist.
  Tainted are the only Lineage naturally immune, their stable Infection bond preventing the corrupted strain from gaining purchase. For everyone else, the only reliable defense is caution: protect yourself around Raider remains, avoid unshielded contact with contaminated blood, and watch the people around you for the early signs. Because the worst part of Bad Brain is not what it does to the afflicted. It is what it forces the people who care about them to decide.