Scientists find that same bacterium caused Justinianic plague and Black Plague

In 2011, DNA evidence confirmed that the infamous Black Plague that ravaged Europe in the 14th century was, as had been suspected for many years, caused by the Yersinia Pestis bacterium. Now a team of scientists have used skeletal microbiology and DNA testing to show that a 6th through 8th century pandemic was caused by the same bacterium.

Historians generally recognize three true "plagues" among the number of disease pandemics that have been recorded. Most people have heard of the Black Plague that struck from 1346 through 1351, but it was actually part of a global pandemic that lasted into the 17th century. The most recent plague, which began in the 19th century and is not officially ended, provides ample microbiological evidence that scientists used to pinpoint its cause as Y. Pestis. (This plague is not related to the influenza pandemic of the early 20th century.)

The earliest recorded plague, known as the Justinianic Plague, killed tens of millions of people, and even infected the Emperor Justinian I, who survived the infection and (involuntarily) later lent his name to the pandemic. The Justinianic Plague has until now not been definitively traced to any specific organism, because of the difficulty in locating skeletal microbiological evidence that is still intact enough for testing. At last, scientists found what they were seeking, in a medieval cemetery at Aschheim in Bavaria. Testing confirms that Y. Pestis is again the culprit, and the team's results were published in May 2013 in the journal PloS Pathogens.

According to a press release from the Institute of Anthropology at Johannes Gutenberg University Mainz (JGU), the new test results "confirmed unambiguously that Y. pestis was indeed the causing agent of the first pandemic, in contrast to what has been postulated by other scientists recently. This revolutionary result is supported by the analysis of the genotype of the ancient strain which provides information about the phylogeny and the place of origin of this plague."

The University of Munich and German Bundeswehr team was led by Dr. Bramanti and her colleague Stephanie Hänsch, with cooperation from scholars from Arizona. An additional research grant has been obtained to study the Justinianic Plague's transmission modes and routes in more detail. With this new grant, the work will now move to the Center for Ecological and Evolutionary Synthesis (CEES) at the University of Oslo in Norway.