The researchers confirmed for the first time, through direct genomic evidence, the bacterium that caused Justinian’s plague, the first documented pandemia, discovering the microbe in Jordan graves, near the epicenter.
The most devastating pandemic of the world was Justinian’s plague / Photo source: Archive
Researchers confirm for the first time the pathogen of the world’s first pandemic
For the first time, the researchers discovered direct genomic evidence of the bacterium that caused Justinian’s plague-the first registered pandemic-in the East Mediterranean region, where the epidemic was first described almost 1,500 years ago.
The revolutionary discovery, made by an interdisciplinary team at the University of South Florida and Florida Atlantic University, together with collaborators from India and Australia, identified Yersinia Pestis, the microbe, in a common pit in the ancient city of Jerash, Jordan, near the epicenter of Pandemic.
This discovery definitively links the pathogen to the plague of Justinian, marking the first pandemic (541-750 AD), and solves one of the long -term mysteries of history.
Justinian’s plague makes victims today all over the world, although it appeared 1,500 years ago
For centuries, historians debated the causes of the devastating epidemic that killed tens of millions, remodeling the Byzantine Empire and changed the course of Western civilization. Despite the circumstantial evidence, the direct test of the responsible microbe has remained evasive so far – a missing piece in the Pandemi story.
Two recently published works offer these much sought after answers, providing new perspectives on one of the most important episodes in the history of humanity.
The discovery also emphasizes the current relevance of the plague: although rare, the cases of Y. Pestis continue to appear throughout the world. In July, a resident of the northern Arizona died from the pneumonic plague, the most lethal form of Y. Pestis, marking the first such fatality in the US in 2007, and last week, another person in California was positively tested for the disease.
“This discovery offers the long -sought -after definitive proof of the presence of Y. Pestis at the epicenter of Justinian’s plague”, states Rays Hy Jiang, the coordinator of the studies and associate professor at the USF Public Health College.
“For centuries, we relied on the written reports that described a devastating disease, but any concrete biological evidence of the presence of the plague was lacking. Our discoveries offer the missing piece of the puzzle, offering the first direct genetic window on how this pandemic took place in the heart of the empire.”
Where the first time appeared the plague of Justinian, the most devastating pandemic of the world. The bacteria was found today in Byzantine tombs
The plague of Justinian appeared for the first time in Pelusium (the current Tell El-Farama) in Egypt, before spreading throughout the Eastern Roman Empire, or Byzantine. Although traces of Y. Pestis had been previously recovered in small villages in western Europe, there had never been evidence within the empire or near the epicenter of pandemic.
“Using ancient DNA targeted techniques, we managed to recover and sequest genetic material from eight human teeth excavated from funeral cameras under the former Roman Hippodrome, a city just 200 miles from the ancient pelusum,” Explains Greg O’Corry-Crowe, co-author and research teacher at Fau Harbor Branch Oceanographic Institute and National Geographic Explorer.
The genomic analysis showed that the victims of the plague wore almost identical stems of Y. Pestis, confirming for the first time that the bacteria was present in the Byzantine Empire between 550-660 AD. This genetic uniformity suggests a rapid and devastating epidemic, according to the historical descriptions of the plague that causes massive mortality.
“The situation in Jerash offers a rare look at how ancient societies reacted to a public health catastrophe,” says Jiang.
Central civic entertainment and pride have become a great cemetery in times of emergency
“Jerash was one of the key cities of the Eastern Roman Empire, an important shopping center with magnificent structures. The fact that a place built for entertainment and civic pride became a meal cemetery in an emergency shows how likely it was for urban centers to be overwhelmed.”
A complementary study, led by USF and without, places the discovery of Jerash in a wider evolutionary context. Analyzing hundreds of Y. Pestis, ancient and modern genomes, including the newly recovered from Jerash, researchers have shown that the bacterium was circulating among human populations for thousands of years before the outbreak of Justinian’s plague.
The team also found that the subsequent plague pandemics, from the black death from the 14th century to the cases and today, have not derived from a single ancestral strain. Instead, they appeared independently and repeatedly from old animal tanks, erupting in multiple waves in different regions and periods. This repetitive model contrasts strongly with the Sars-COV-2 pandemic (Covid-19), which started from a single transmission event and has prevailing through transmission between people.
Together, the revolutionary discoveries change the understanding of the way they appear, repeat and spread the pandemic and explain why a persistent phenomenon of human civilization remain. The research emphasizes that pandemic are not unique historical catastrophes, but repeated biological events, influenced by people’s assembly, mobility and environmental changes – themes as relevant today.
“This research was both scientifically captivating and staff. It offered us an extraordinary opportunity to study human history through the prism of ancient DNA, in a time when we lived a global pandemic.” says O’Corry-Crowe.
The researchers worked with ancient human remains, thousands of years old, to solve the mystery of the first pandema that humanity faced
“Equally deep was the experience of working with ancient human remains-individuals who lived, suffered and died centuries ago-and to use modern science to recover and share their stories. It is a humiliating reminder of our common humanity over time and an emotional will.”
Although very different from Covid-19, both diseases highlight the sustainable connection between connectivity and pandemic risk, as well as the reality that some pathogens cannot be completely eradicated.
“We have faced the plague for several thousand years and people still die because of it,” says Jiang. “Like Covid, it continues to evolve, and the obvious container measures cannot eliminate it. We must be cautious, but the threat will never disappear.”
Based on the discovery in Jerash, the team now extends its research in Venice, Italy, and Lazaretto Vecchio, an island dedicated to quarantine and one of the most important burial sites of the victims of the black plague. Over 1,200 evidence in this common pit dating from the period of black death are now kept at the USF, offering an unprecedented opportunity to study as early public health measures, urban vulnerability and cultural memory.
Other researchers who have contributed to this study come from the University of South Florida and Florida Atlantic University.
The research was supported by USF Provest’s Create Award, USF College of Public Health Research and USF Microbiome Institute, as well as international collaborations in the field of archeology and genomics.
