Ancient DNA reveals how plague kept returning for 400 years after the Black Death

Ancient DNA reveals that plague repeatedly returned to Europe for more than 400 years after the Black Death, evolving into new lineages and spreading through trade, migration, and war. Researchers also developed a method to date ancient plague genomes more precisely, linking many of them to specific outbreaks recorded in historical sources. The Black Death is best known for the catastrophic wave of plague that swept through Europe between 1347 and 1353, killing millions of people. But the disease did not vanish once that initial disaster passed. Plague returned again and again for more than four centuries, repeatedly disrupting cities, economies, and societies across Europe and surrounding regions.

A study led by researchers at the University of Tartu is now offering a much more detailed look at what happened during those centuries. By analyzing DNA from the plague bacterium preserved in archaeological human remains, scientists were able to reconstruct how the disease spread, evolved, and repeatedly reappeared long after the Black Death. The team reconstructed 26 genomes of Yersinia pestis, the bacterium that causes plague, from human remains recovered at 11 archaeological sites in Estonia, Russia, England, the Netherlands, and Switzerland. The samples date from the fourteenth through the eighteenth centuries, covering a large portion of the period known