The origins of the Black Death, the plague that caused a pandemic lasting hundreds of years, have been pinpointed to a lake region in modern-day Kyrgyzstan in 1338.
Less than a decade later, plague first entered the Mediterranean on trade ships transporting goods from the territories of the Golden Horde in the Black Sea.
The disease then spread across Europe, the Middle East and northern Africa, killing up to 60 per cent of the population in an outbreak that was called the Black Death.
This first wave became a 500-year-long pandemic, the so-called Second Plague Pandemic, which lasted until the early 19th century.
Until now, estimates had been put the beginnings of the strain to sometime between the 10th and 14th centuries.
Now, a study of tombstones excavated almost 140 years ago near Lake Issyk Kul, in what is now Kyrgyzstan, show that an epidemic devastated a trading community in 1338 and 1339.
Two sites studied were at the heart of the international trade route known as the Silk Road. They indicate that individuals died in those years of an unknown epidemic or “pestilence”.
Since their first discovery, the tombstones inscribed in Syriac language, have been a cornerstone of controversy among scholars regarding their relevance to the Black Death of Europe, researchers said.
They combined a DNA study with research into the inscriptions on the stones.
Dr Philip Slavin, of the University of Stirling in the UK, told The National: “It is very plausible that the 1338-1339 strain originated and evolved in local marmot plague reservoirs of the Tian Shan region, rather than in a faraway region.”
He said some of the local inhabitants were undoubtedly engaged in international trade based on objects found in their graves including pearls harvested in waters such as the Arabian Gulf, corals and shells likely to have been harvested in the Mediterranean Sea, plus coins, silk and golden brocade cloths.
“Another important question is how did the same plague wave spread from Central Asia into Europe in the 1340s?” he said.
“In our paper, we did touch upon the fact that the local Christian community at Kara-Djigach, from where our sequenced samples come from, were involved in long-distance trade across Eurasia and it was that trans-regional trade that may have been a paramount factor contributing to the spread of the plague.”
The team’s first results were very encouraging, as DNA from the plague bacterium, Yersinia pestis, was identified in individuals with the year 1338 inscribed on their tombstones.
“We could finally show that the epidemic mentioned on the tombstones was indeed caused by plague”, Dr Slavin said.
Researchers have previously associated the Black Death’s initiation with a diversification of plague strains, a so-called Big Bang event.
“We found that the ancient strains from Kyrgyzstan are positioned exactly at the node of this massive diversification event. In other words, we found the Black Death’s source strain and we even know its exact date [meaning the year 1338]”, said Maria Spyrou, lead author and researcher at the University of Tübingen in south-west Germany.
However, the researchers pointed out in their paper, published in the journal Nature, that plague is not a disease of humans, but survives within wild rodent populations across the world, in so-called plague reservoirs.
Hence, the ancient Central Asian strain that caused the 1338-1339 epidemic around Lake Issyk Kul must have come from one such reservoir.
“We found that modern strains most closely related to the ancient strain are today found in plague reservoirs around the Tian Shan mountains, so very close to where the ancient strain was found. This points to an origin of Black Death’s ancestor in Central Asia”, said Johannes Krause, senior author of the study and director at the Max Planck Institute for Evolutionary Anthropology.
They said the study demonstrates how investigations of well-defined archaeological contexts, and close collaborations among historians, archaeologists and geneticists can resolve big mysteries of our past.
