Researchers confirmed Yersinia pestis, later responsible for the Black Death, caused the Justinian Plague 1,500 years ago.
They traced the bacterium to its epicentre for the first time, uncovering the source of the earliest pandemic.
Scientists discovered Yersinia pestis DNA in a mass grave beneath Jerash’s ancient ruins in Jordan.
Lead author Rays HY Jiang said the findings provide the first direct genetic evidence of the Justinian Plague.
Justinian Plague Devastated Eastern Mediterranean
The pandemic began in 541 CE and spread rapidly across the Byzantine Empire and surrounding regions.
Historians estimate it killed between 15 and 100 million people over two centuries of recurring outbreaks.
Researchers confirmed Yersinia pestis caused the pandemic, the same bacterium behind later outbreaks like the Black Death.
Fleas infesting rodents, especially rats near humans, spread the bacterium, while pneumonic transmission allowed direct human-to-human infection.
DNA Unlocks 1,500-Year-Old Mystery
The team examined eight human teeth from burial chambers under Jerash’s Roman hippodrome using advanced DNA techniques.
Victims shared nearly identical strains of Yersinia pestis, confirming its presence in the empire between 550 and 660 AD.
The findings indicate a fast, deadly outbreak, matching historical accounts of mass fatalities in urban centers.
Jiang noted that Jerash’s transformation from civic hub to mass cemetery shows how overwhelmed cities became during the crisis.
Plague Continues to Evolve
Related research shows Yersinia pestis circulated among humans long before the Justinian outbreak.
Later pandemics, including the Black Death and modern cases, emerged independently from animal reservoirs.
Jiang warned that plague, like COVID, continues to evolve and cannot be fully eradicated, posing an ongoing threat to humanity.
