The bubonic plague bacillus was found in the genome of two individuals who died 3,800 years ago in Russia, pushing the putative age of the disease back by at least a thousand years.
The bubonic plague has just taken a big hit. According to a published study in NatureCommunications, the most terrifying disease in human history already existed in the Bronze Age. In a tomb in the Samara region of Russia, archaeologists unearthed specimens of Yersinia pestisthe plague bacillus, 3800 years old.
From the origin of evil
The bubonic plague is responsible for some of the worst pandemics in history, from the Plague of Justinian, which ravaged the Mediterranean basin from the 5and century, until the Black Death, which mowed down a good third of the European population in the middle of the 14and century. But if the exploits of this serial killer are well known to historians, the beginnings of the bubonic plague remain mysterious.
Genetic studies already dated the origin of the bacillus to the end of the Neolithic or the beginning of the Bronze Age, between 5000 and 3500 years before today. But the strains identified at that time are devoid of a faculty essential to any Yersinia pestis self-respecting: that of surviving in the intestine of fleas, and therefore of colonizing any warm-blooded animal. The oldest strain with this genetic trait was found in Armenia, on a site “only” 2900 years old.
Two people in one grave
Hence the find. By analyzing the teeth of nine individuals found in Samara (belonging to the so-called Srubna culture), the researchers identified two genomes infected with the plague bacillus. These are two individuals buried face to face in the same grave, and no doubt died of disease. By reconstructing the genome of the offending strain, they showed that it possessed the genetic material allowing it to colonize fleas.
“This strain is the oldest sequenced to date that contains the virulence factors considered characteristic of bubonic plague,” summarize the researchers in a press release from the Max Planck Institute. Here is the bubonic plague which suddenly takes a thousand years: we now know that it was already raging some 3800 years ago. And the Bronze Age is getting darker.
The two individuals from the Samara site infected with the plague bacillus. (VV Kondrashin and VA Tsybin, all rights reserved.)
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