Bubonic / Pneumonic / Septicemic Plague: Yersinia Pestis

it's been in Britain for a long time.

Researchers have found 4,000-year-old plague DNA in Britain - the oldest evidence of the disease in the country.

Scientists identified three cases of Yersinia pestis, the bacteria causing the plague, in human remains - two in a mass burial in Somerset, and one in a ring cairn monument in Cumbria. The team took small skeletal samples from 34 individuals looking for the presence of Yersinia pestis in teeth. The dental pulp was examined as it traps the DNA of infectious diseases.

Francis Crick Institute scientists worked with the University of Oxford, the Levens Local History Group and the Wells and Mendip Museum to make the discovery.

Pooja Swali, first author and PhD student at the Crick, said: "The ability to detect ancient pathogens from degraded samples, from thousands of years ago, is incredible. These genomes can inform us of the spread and evolutionary changes of pathogens in the past, and hopefully help us understand which genes may be important in the spread of infectious diseases. We see that this Yersinia pestis lineage, including genomes from this study, loses genes over time, a pattern that has emerged with later epidemics caused by the same pathogen."