Dementia’s origins are complex, involving genetic, vascular, and lifestyle factors. Emerging evidence links neurotropic herpesviruses to dementia via neuroinflammatory processes. In Finland, dementia prevalence is rising, yet research on herpes zoster (HZ) and cognitive decline remains scarce. This project uses FinRegistry data to explore HZ-dementia links and document HZ prevalence and vaccination patterns, offering insights for public health and dementia prevention strategies.