Researchers found tiny bits of DNA in the teeth of two German victims killed by the Justinian plague about 1,500 years ago. With those fragments, they reconstructed the genome of the oldest bacteria known.
They concluded the Justinian plague was caused by a strain of Yersinia pestis, the same pathogen responsible for the Black Death that struck medieval Europe. The study was published online today in the journal, Lancet Infectious Diseases.
Couple of years ago daughter told me about questions from some researchers as to whether the plague that struck in some areas was actually Bubonic or something else. This clears that up for at least one region.