Consider the mid-1950s, just after the Dr. Jonas Salk’s polio vaccine had been approved. At the time, young children were vaccinated by the millions. But teenagers were also susceptible to polio, and they were not being vaccinated. That’s when Elvis — yes, that Elvis — became involved. In 1956, in an effort to close the immunization gap that existed between those who got vaccinated for polio and those who didn’t, Elvis Presley was approached to popularize the polio vaccine among American teens. In October of that year, Elvis got vaccinated on national television.