Syndrome Johnny

A contaminated blood donation initiates an outbreak that causes some immediate deaths and a persistent syndrome of endocrine imbalance, digestive oddities, and emotional disturbance in survivors. Investigators narrow initial cases to a handful of itinerant donors but cannot pin down a single culprit as many carriers recover and silently spread the agent, producing successive epidemics that kill millions and leave survivors with chronic glandular troubles. Over decades the pathogen becomes endemic in carrier form, alters birth rates and demographics, and spawns popular myths of a wandering carrier figure, driving bureaucratic and forensic efforts to match prints and reports to a human origin.