It made a huge impression on many children in the 50s still - there were still tens of thousands dying and being paralyzed each year until the late 50s, and by this point they were predominantly small children being affected. My parents are in their early 60s and they remember it well - when she was five her friend was partially paralyzed for life by it. https://www.historyofvaccines.org/content/us-polio-cases-195... had friends who died. They were given behavior restrictions.