Pandemic origins: Scientists have finally discovered the genome of the bacterium behind the world’s first recorded pandemic that struck the eastern Mediterranean about 1,500 years ago, as per a report.
Researchers have found ‘Yersinia pestis’, the bacterium that causes plague, in a mass grave in the ancient city of Jerash, Jordan, close to the pandemic’s epicenter, as reported by the Independent. This finding, published in the journal Genes, confirms that ‘Y pestis’ was responsible for the Justinian Plague, solving a long-standing mystery, according to the report.
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The Independent reported that the Justinian Plague, which lasted from 541 AD to 750 AD, taken lives of tens of millions of people and reshaped the Byzantine Empire. But until now, what actually caused the devastating outbreak was widely debated. While there was some indirect evidence, direct proof of the microbe was missing, as per the report.
The study’s co-author Rays HY Jiang from the University of South Florida, said that “This discovery provides the long-sought definitive proof of Y pestis at the epicentre of the Plague of Justinian,” as quoted by the Independent.
Jiang highlighted that “For centuries, we have relied on written accounts describing a devastating disease, but lacked any hard biological evidence of plague’s presence. Our findings provide the missing piece of that puzzle,” as quoted in the report.
Historical records show that the plague first appeared in Pelusium, which is present-day Egypt, before spreading across the Eastern Roman Empire, according to the report. While Y pestis evidence had been found thousands of miles away in small western European villages, but until now, there was no proof from within the empire itself, as per the Independent report.
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Another author of the study, Greg O’Corry-Crowe, shared that they found this “Using targeted ancient DNA techniques, we successfully recovered and sequenced genetic material from eight human teeth excavated from burial chambers beneath the former Roman hippodrome in Jerash, a city just 200 miles from ancient Pelusium,” as quoted by the Independent.
The DNA analysis helped uncover that the plague victims had carried almost identical strains of Y pestis, which confirmed that the bacterium was present within the Byzantine Empire between 550AD and 660AD, reported the Independent.
This finding points out to the rapid, devastating outbreak, which is consistent with historical descriptions of the plague causing mass deaths, according to the report.
Jiang explained that, “Jerash was one of the key cities of the Eastern Roman Empire, a documented trade hub with magnificent structures,” adding, “That a venue once built for entertainment and civic pride became a mass cemetery in a time of emergency shows how urban centres were very likely overwhelmed,” as quoted by the Independent.
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A companion study published in Pathogens revealed that the bacterium circulated among humans for millennia even before the Justinian outbreak took place, as per the report. This also indicates that later pandemics, from the Black Death of the 14th century to rare cases today, did not come from a single ancestral strain, according to the Independent report. Different outbreaks appear to have emerged independently and repeatedly from longstanding animal reservoirs, reported the Independent.
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The study’s findings highlight that pandemics are not one-time catastrophes but recurring events driven by human congregation, mobility, and environmental changes, factors that still are relevant even today, as per the report.
Jiang said that, “We’ve been wrestling with plague for a few thousand years, and people still die from it today,” adding, “Like Covid, it continues to evolve, and containment measures evidently can’t get rid of it. We have to be careful, but the threat will never go away,” as quoted by the Independent.
What did scientists discover about the Justinian Plague?
They finally found direct genetic proof that the bacterium Yersinia pestis caused the pandemic.
What is Yersinia pestis?
It’s the bacterium that causes plague, including the Black Death and other deadly outbreaks.
