In 1918, a flu pandemic killed more than 50 million people worldwide. Forty years later, it nearly happened again. This week on Sidedoor we go back to a time when the viruses were winning, and we remember one man, Dr. Maurice Hilleman, whose vaccine virtuosity helped turn the tide in the war against infectious diseases.

We’ve updated this episode with a bonus interview to reflect on what we’ve learned from our current pandemic. If you want to learn more, please see vaccinesandus.org.