It killed 25 million people.. How did the most deadly pandemic spread to Europe?

The study showed that the black plague, which is considered one of the most deadly epidemics in human history, most likely arose in the year 1338 in the foothills of the Tian Shan Mountains near Lake Issyk-Kul in present-day Kyrgyzstan, before a new strain of plague bacteria was transmitted through trade routes to the Black Sea regions.

The transmission of the plague from Asia to Europe

The fleas, which carry the bacteria Yersinia pestis In their intestines, they transmitted the infection to rodents, which in turn spread the disease widely, before these fleas began biting humans when the number of mice decreased.

Via grain ships heading to Europe, infected fleas arrived in European ports starting in 1347, bringing with them epidemic and death.

In just six years, the plague claimed the lives of between 30 and 60 percent of the European population, or Approximately 25 million people.

Historic European famines

The study conducted by the teams of Professor Ulf Büntgen from the University of Cambridge and Professor Martin Bauch from the University of Leipzig, and published in the journal Communications Earth & Environment, focused on the reasons for this sweeping spread in that period.

The researchers relied on dendrochronology, which studies the growth rings of trees, and noticed an abnormal decrease in the process of logging in forests. The Spanish Pyrenees Mountains for several consecutive years, which is a rare occurrence.

Significant drop in temperatures

The results also showed that this was due to a significant drop in temperature and light intensity during the years 1345 and 1346.

After reconstructing the climate prevailing in that period, it was found that the most likely cause of this sharp change was one or more volcanic eruptions in 1345, the locations of which were not precisely determined. This climate disturbance led to the destruction of crops and the occurrence of widespread famines.

Professor Martin Bauch pointed out that major Italian cities such as Venice, Genoa, and Pisa had established more than a century ago trade networks linking the Mediterranean Sea to the Black Sea, which initially helped them confront food shortages, but in the end it contributed to accelerating the spread of the plague on a larger scale, so that these economic solutions turned into a global health disaster.