Yellow fever doesn’t have the cachet of the Black Death or the Asian flu, but the mosquito-borne disease nicknamed “the American Plague” has tormented the world for centuries.

The U.S. Centers for Disease Control and Prevention estimates the virus causes 200,000 cases and 30,000 deaths each year, and not just in the tropics. The disease first struck New York City in 1668, followed by at least 25 major outbreaks in the Americas, including an 1878 epidemic in the Mississippi River Valley that killed 20,000 people.

There is a vaccine, developed after the opening of the Panama Canal in 1912 by scientists throughout the world. However, historically it needed to be freeze-dried, a process prone to mechanical issues until it was refined in the early 1950s by National Drug in the small hamlet of Swiftwater, Pennsylvania.

You can read the story of this and other vaccine innovations in The Spirit of Swiftwater, a chronicle of the pioneers of immunization who fought to revolutionize healthcare in America.