Scientists confirmed Yersinia pestis triggered the Justinian Plague, the world’s earliest recorded pandemic 1,500 years ago.
They traced the bacterium’s epicenter for the first time, solving a mystery long debated in historical accounts.
Discovery in Jordan Mass Grave
Researchers discovered Yersinia pestis in a mass grave beneath the ruins of Jerash in Jordan.
This evidence provided the first biological confirmation of the plague described in centuries of texts.
Rays HY Jiang, study lead and professor at USF, said the findings filled a crucial missing piece.
He explained that the DNA offered a genetic window into how the pandemic unfolded across the empire.
The First Global Pandemic
The plague began in 541 CE and spread through the Byzantine Empire and the eastern Mediterranean.
Historians believe it caused 15 to 100 million deaths during two centuries of recurring outbreaks.
The zoonotic bacterium spread through fleas on rodents and, in pneumonic form, between humans.
Researchers confirmed it matched the same microbe later responsible for the Black Death centuries afterward.
DNA Evidence From Jerash
An interdisciplinary team analyzed eight teeth from burials under Jerash’s ancient Roman hippodrome.
Genetic tests revealed nearly identical Y pestis strains, proving a swift outbreak between 550 and 660 AD.
Jiang said Jerash, once a thriving trade hub, became a cemetery overwhelmed by mass deaths.
A related study showed plague circulated for millennia and arose repeatedly from animal reservoirs.
Jiang warned plague, like COVID, continues evolving, and no measures can eliminate it entirely.
