The bubonic plague, a pandemic that may have killed about half of Europe’s population in the 14th century, is likely the result of an epidemic in what is now Kyrgyzstan, in Central Asia.
The DNA of disease-causing bacteria was identified in the remains of people buried in the region in 1338, less than a decade before the bubonic plague arrived in Europe.
The genetic material of microbes from Kyrgyzstan is practically identical to that found in the victims of the plague in Europe, according to research on the subject that has just been published in the scientific journal Nature. And inscriptions on Asian tombs suggest it was already an epidemic – most deaths at the time at the site appear to have been caused by an infection.
The work was coordinated by Maria Spyrou and Johannes Krause from the Max Planck Institute for Evolutionary Anthropology in Germany and Philip Slavin from the University of Stirling (UK).
Combining new genomic data with what was already known about the archaeological aspects and history of the bubonic plague, the study has the potential to end a long debate about the origins of the disease, which is considered the most devastating pandemic in human history.
“We have known for a long time about the existence of these Christian cemeteries in Kyrgyzstan, where epigraphic material was found. [inscrições] wonderful, “Slavin told an online news conference.
In the 14th century, although the region was ruled by the Mongol Empire, the local Christian community adopted Syriac in its texts (close to Aramaic, which was the mother tongue of Jesus and the apostles).
The tombstone of one of the tombs, with the image of a cross, reads: “1649. [equivalente a 1338 no nosso calendário]year of the tiger [‘Bars’ na língua turca]. This is the tomb of the faithful Sanmaq. He died of ‘mawtane’ [pestilência, em siríaco]”Similar references appear in two modern cemeteries in the region of Lake Isik-Kul, near the mountains on today’s border with Kazakhstan.
This trace has already pointed to the territory of Kyrgyzstan as a possible source of bubonic plague, whose first records in Europe date back to 1346, in the region of Crimea (which is now disputed by Russia and Ukraine). The genomes of the bacterium Yersinia pestis found by researchers in Christian tombs have exactly those characteristics that would be expected from the close common ancestor of the bacterium that will begin to decimate Europeans a few years later.
In addition, very similar microbial strains are still circulating in wild rodent (tree-headed) populations in Kyrgyzstan. Animals are considered a natural reservoir of bacteria – today people only become infected when they come in contact with animals.
If this place can seem relatively remote and undiscovered today, it is important to remember that the situation in the late Middle Ages was very different.
“It’s a community of merchants who had long-distance connections from many different places, judging by the artifacts found by archaeologists in the region,” Slavin recalls.
The list includes items from the Pacific and Mediterranean coasts, China (relatively close to the cemetery) and the Middle East. The Christian group to which the dead belonged, the Nestorian Church, was spread over a wide area of Eurasia, reaching as far as India. The unifying presence of the Mongol Empire also facilitated trade.
That is, these ties could have facilitated the spread of the initial epidemic to the west. The exact moment when the pandemic started, however, is a little more complicated to explain.
“In a way, it’s the perfect storm that combines a lot of random factors,” says Johannes Krause. “An important element is that several centuries have passed since the bubonic plague epidemic spread to Europe, which means that in the 14th century, the bacterium began to infect a population that had no natural defense against it.”
lack of cleanliness
Another central factor is, of course, why Europeans and other peoples of the time. The main form of disease transmission was flea bites carried by rats. In other words, dirty cities full of people living with rats due to lack of hygiene were full of plague.
“In fact, fleas only ended up sucking people’s blood when the rats died of weight. In other words, humans were in some ways just collateral damage caused by a rodent pandemic,” Krause explains.
The main signs of the disease were the so-called buboes, large inflammation of the lymph nodes in the groin, neck and armpits. The infected had a high temperature, vomited blood and died in a few days.
Although sporadic cases still occur today, the huge improvement in hygienic conditions and the availability of antibiotics have stopped the outbreak of bubonic plague, at least for now. (Reinaldo José Lopes / Folhapress)