The oldest strain of Yersinia pestis, the bacteria that causes the plague, was found in the remains of a 5,000-year-old hunter-gatherer in what is now Latvia.
The Black Death is the second plague pandemic in history, peaking in 1346-1353, with repeated outbreaks continuing until the 19th century. Tens of millions of people have become victims of the disease: according to various estimates, from 30% to 60% of the population of Europe died from the disease. The bacterium that causes the plague is called Yersinia pestis, and scientists have recently discovered its oldest strain. Genetic analysis, published in the journal Cell Reports, suggests that it was probably less contagious and less deadly than its medieval version.
The hunter-gatherer who spread the plague 5 thousand years ago was a man between 20 and 30 years old, whose remains bear the code name RV 2039. His remains, along with another skeleton, were found in the late 1800s in the Rinnukalns region of modern Latvia. … The remains of both soon disappeared until 2011, when they reappeared in the collection of the German anthropologist Rudolf Virchow. Since this rediscovery, archaeologists have found two more graves in Latvia, a total of four sets of remains, probably from the same group of hunter-fisher-gatherers.
In the new study, scientists used tooth and bone samples from all four hunter-gatherers to sequence their genomes and then tested them for bacterial and viral pathogens. As the authors of the work note, they were extremely surprised to find evidence of the presence of Y. pestis in RV 2039. After reconstructing the bacterial genome and comparing it with other ancient strains, the researchers determined that Y. pestis RV 2039 was indeed the oldest strain ever discovered.