People with acquired human prion disease are often first alerted by subtle, rapidly changing neurologic symptoms: new problems with memory or concentration, clumsiness or balance trouble, and mood or behavior changes that family and friends notice over weeks to a few months. As it progresses, blurred or double vision, jerky movements, slurred speech, and disturbed sleep can appear, prompting urgent medical evaluation. Many first seek help because these changes are strikingly fast compared with typical age-related memory issues or stress-related symptoms.