When I started writing about research on Yersinia pestis and the Black Death, I was amazed at the ability to recover 14th century bacterial DNA from human remains, show Y. pestis was the caustive agent of the Black Death and then sequence the strain to compare to modern Y. pestis strains. The publications I read always mentioned the three waves of pandemics that devastated human populations in the introduction, and the Black Death was not the oldest one. The putative first pandemic was the Plague of Justinian in the 6th century, named after the Byzantine emperor. Like with the Black Death, there is debate about whether Y. pestis is the causative agent of the Plague of Justinian. The research published in PLOS Pathogens built on earlier work to isolate and genotype the suspected Y. pestis causative agent from human remains in 6th century graves, but this time with more stringent protocols enacted to answer critics who questioned the authenticity of earlier results. Continue reading “Ancient Samples Confirm the Cause of the 6th Century Plague Pandemic”