 His work is estimated to have saved about 8 million lives a year. One single scientist responsible for over 40 vaccines. Chickenpox. Adenovirus. Measles. Mom's rubella. Japanese encephalitis. Who you'd think would be a household name. Among the group of pediatricians who give his vaccines, no one heard of him. No one. That's on the next Radiolab. Sunday at noon on KUAR, Little Rock Public Radio.