The 1918 influenza pandemic, the deadliest event in American public-health history with about 675,000 dead, tested what the Public Health Service could actually do. Surgeon General Rupert Blue stood up a task force under Wade Hampton Frost, and Congress voted $1 million without dissent, but the service could command nothing. Its lasting legacy was method, as house-to-house surveys helped found modern epidemiology.
Death tolls are estimates, and the pandemic's geographic origin is disputed among historians. The name Spanish flu reflects wartime censorship, not origin, and historians stress that the decisive variation in outcomes was local.