Today's plague pathogen was also the cause of 'Black Death 600 years ago

A team of German and Canadian scientists has shown that today’s plague pathogen was also responsible for the Black Death, the most deadly outbreak of disease ever that claimed the lives of one-third of Europeans in just five years from 1348 to 1353.

The University of Tubingen’s Institute of Scientific Archaeology and McMaster University in Canada have been able to confirm that the bacterium Yersinia pestis -- known to cause the plague today -- was behind the great plague.

The international team of researchers has for the first time been able to decode a circular genome important for explaining the virulence of Y. pestis.

It is called pPCP1 plasmid and comprises about 10,000 positions in the bacterium’s DNA.

The sample was taken from skeletons from a London plague cemetery. The working group in Tubingen, led by Dr. Johannes Krause used a new technique of “molecular fishing” - enriching plague DNA fragments from tooth enamel and sequencing them using the latest technology.

In this way, the fragments were connected up into a long genome sequence, which turned out to be identical to modern-day plague pathogens.

“That indicates that at least this part of the genetic information has barely changed in the past 600 years,” Science Daily quoted Krause as saying.

The researchers were also able to show that the plague DNA from the London cemetery was indeed medieval.

“Without a doubt, the plague pathogen known today as Y. pestis was also the cause of the plague in the Middle Ages,” added Krause.

The results of the research were published in the Proceedings of the National Academy of Sciences.