Smallpox is a deadly virus. At one point, it killed almost 1 in 3 people who had it. Almost 300 million of those deaths were in the 20th century alone. It was extremely painful, highly contagious and many people thought it would be impossible to get wipe out—until it was. On May 8, 1980. the 33rd World Health Assembly declared the world free of smallpox. This marked the first—and only—time a human disease was eradicated globally. Epidemiologist and host of the podcast Epidemic: Eradicating Smallpox Céline Gounder has been looking into this history. Today, she shares the intense journey to eradicate smallpox in Bangladesh (spoiler alert: there are literal speedboats) and reflects on what this history tells us about the importance of healthcare that meets the needs of individuals and communities today. Click here to check out the second season of Céline's podcast from NPR partner KFF Health News. What science story do you want to hear next on Short Wave? Email us at shortwave@npr.org.