The Black Death epidemic, which has now appeared in Central Asia, and now in Kyrgyzstan, has put an end to the question of nearly seven centuries.
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Thanks to ancient human DNA extracted from a 14th-century burial ground in northern Kyrgyzstan, researchers have been able to trace the source. Their findings, published Wednesday in the journal Nature, have sparked a long-running debate among historians.
The Black Death epidemic reached Europe in 1346 via cargo ships from the Black Sea via the Mediterranean. In just eight years, the “black death” killed up to 60% of the population of Europe, the Middle East and North Africa. And marked the beginning of a long wave of epidemics that reappeared between 500 years.
Where was she born? One of the most commonly advanced ways is to join China, but no strong evidence can support this theory.
“I have always been fascinated by black death and solving the mystery of its origin is one of my dreams,” the disaster historian, one of the authors of the study, Bill Slaw, told a news conference.
A professor at the University of Stirling (Scotland) was aware of the existence of two medieval burial mounds near Lake Isik Gul in Kyrgyzstan, which were excavated in the late 19th century.
Of the more than 400 tombs, one hundred are dated to an exact date: 1338-1339. In Old Syriac, the ellipse with the inscription “Pistils Death”. Seven or eight years before the Black Death invaded Europe, there were many signs of an extraordinary high death toll within a community.
To find the cause of death, the researchers searched the tooth DNA of seven skeletons. “Toothpaste is a valuable resource because it is a highly vascularized area that gives a greater chance of detecting pathogens in the blood,” Maria Spiro, of the University of Tbingen in Germany, told AFP.
DNA can be sorted – a delicate job because it was fragmented – and then compared to a database containing the genes of thousands of bacteria.
Verdict: Bodies are infected with the bacterium Yersinia pestis, which is transmitted to humans by Bacillus, a rodent plague that causes black plaque. So this community has fallen victim to the same atrocities that hit Europe a few years later.
Genetic analysis of Yersinia pestis also revealed that it is an ancestral strain of bacteria. Blake is at the base of the “genetic tree”.
Scientists link the origin of the Black Death in Europe to a genetic “Big Bang” during which stem bacteria differ greatly.
The strains found in Kyrgyzstan are exactly “at the center of this massive diversification” that occurred in the 1330s. According to Maria Spiro, this part of the world confirms that Tian Shan was actually the starting point of the expansion.
In addition, among the rodents that live in Tian Shan today, researchers have identified a strain of the bacterium closest to infected humans in 1338-1339, “the closest found in the world,” said Johannes Cross. Max Planck Institute, co-author of the study.
These were Christian communities, ethnically diverse (Mongols, Uyghurs …), who traded long distances according to the rites they discovered: Pacific pearls, corals from the Mediterranean, silk garments … “Silk Roads at heart, they had to travel a lot, the Black Sea Played a role in spreading the disease through, ”said Bill Slavin.
Plague has never been wiped off the face of the earth: thousands of people continue to be affected every year, especially in Central Asia. In the Tian Shan Mountains, marmots are the main animal reservoir of the disease.
A deadly epidemic like the Middle Ages is fortunately not to be feared: the bacterium is less malignant, but the health conditions and the use of antibiotics have nothing to do with the past.
