By: April Sheng
Researchers have been searching for decades about how the infamous plague, the Black Death, started. Today, it is still a mystery, but they may have found a clue to the puzzle; a piece of information to lead us to the answer.
Where was this information found? It was discovered recently in the pulp of teeth from bodies buried in the 14th century. Based on their analysis of the preserved genetic material, researchers report that the Black Death arrived around 1338 near Issyk Kul; a lake in a mountainous region in what is now Kyrgyzstan. People in a small nearby settlement of traders were infected first, years before it terrorized Eurasia. Historians followed the path of the plague, it apparently began in China or near the western border of China and moved along trade routes to Europe, North Africa and the Middle East.
However, Monica H. Green, a medical historian and independent scholar who was not involved in the new paper, said that historians would never be able to answer the question they raised: Was it really Yersinia pestis that caused this massive pandemic?
The hunt for the origin of the plague goes back more than a decade, to when the group that led the latest study stunned archaeologists with their report that they could find plague bacteria DNA in the teeth of skeletons; that study involved plague victims in London. Since that study, the group inspected countless genetic material from plague victims at different places and began building a DNA family tree. It and other researchers described that the tree had a trunk and then, all at once, seemed to explode into four branches of Y. pestis strains whose descendants are found today in rodents. They then began to search to find when and where it occurred.
Dr. Slavin – a latecomer to the group that analyzed plague victims – realized that the gravestones he found were dated. Some had inscriptions saying, in an old language, Syriac, that the person had died of “pestilence.” And the population’s death rate had soared in the year those people died. “That brought it to my attention because it wasn’t just any year,” Dr. Slavin said. It was 1338, “just seven or eight years before the Black Death came to Europe.” The group also reports that the rodents that spread the bacteria to those victims were marmots. Marmots in that area today have fleas that carry a type of Y. pestis that appears to be derived directly from the ancestral strain. And the researchers report that the strain in Kyrgyzstan is from the trunk that exploded into four strains. Their research indicates that the plague’s spread was most likely through trade routes and not, through military actions a century, which some historians have suggested. Dr. Green said she was convinced that the group had found plague victims in Kyrgyzstan. But she said the evidence available now was insufficient to justify its bold claims. “Stay tuned,” Dr. Green said, adding she expected that more evidence might emerge.
But for now, they have pinpointed a clue to the start of the Black Death.