Researchers confirmed Yersinia pestis caused the Justinian Plague, the world’s first recorded pandemic 1,500 years ago.
They traced the bacterium to Jerash, Jordan, uncovering its epicentre for the first time.
Scientists analyzed a mass grave, providing the first direct biological proof of the deadly outbreak.
Lead author Rays HY Jiang said the study offers the first genetic insight into the pandemic’s impact.
How the Plague Spread
The Justinian Plague began in 541 CE and devastated the eastern Mediterranean and Byzantine Empire.
Historians estimate it killed 15 to 100 million people across two centuries of recurring outbreaks.
Researchers confirmed Yersinia pestis, the same bacterium behind later plagues like the Black Death, caused the pandemic.
Fleas on rodents, especially rats near humans, transmitted the bacterium, and pneumonic cases spread directly between people.
Unlocking the Ancient Epidemic
Researchers examined eight teeth from burial chambers beneath Jerash’s Roman hippodrome using advanced DNA techniques.
The victims shared nearly identical Yersinia pestis strains, confirming the bacterium struck between 550 and 660 AD.
The DNA evidence suggests a rapid, lethal outbreak, matching historical accounts of mass fatalities.
Jiang said the site reveals how urban centres struggled to handle sudden public health crises.
Plague’s Enduring Legacy
A related study found Yersinia pestis circulated among humans long before the Justinian Plague.
Later outbreaks, including the Black Death and modern cases, arose independently from animal reservoirs.
Jiang warned the bacterium continues to evolve, and humans must remain vigilant against this persistent threat.