Researchers from the University of Bradford, in collaboration with the Francis Crick Institute and University College London (UCL), have uncovered groundbreaking insights into the evolution of Borrelia recurrentis—the bacterium responsible for recurring fever—through ancient DNA analysis of human remains from across England.
The study identified traces of Borrelia recurrentis in four samples dating between 2,300 and 600 years ago. These samples were collected from archaeological sites in Canterbury (Kent), Poulton (Cheshire), South Gloucestershire, and notably from Wetwang Slack in East Yorkshire, where a female skeleton contributed significantly to this discovery.
Borrelia recurrentis is a bacterial pathogen typically transmitted by lice rather than ticks, causing relapsing fever—a disease characterized by repeated episodes of high fever. While related to the bacteria causing Lyme disease, it is mostly seen today in overcrowded and unsanitary conditions such as refugee camps.
The research reveals that over millennia, the bacterium evolved and shifted its vector from ticks to lice. This transition appears to coincide with key changes in human society—namely, living in closer quarters and the emergence of wool trading—which may have facilitated its spread.
Dr. Jo Buckberry from the University of Bradford’s Department of Archaeology and Forensic Science expressed her enthusiasm:
“Detecting diseases in ancient skeletons that leave no visible traces is like traveling back in time. Linking Bradford’s historic wool trade with the evolutionary story of this bacterium is truly thrilling. It’s fascinating to see how changes in human lifestyle influenced the complex dance between microbes and their hosts.”
Dr. Pontus Skoglund, group leader at the Francis Crick Institute’s Ancient Genomics Laboratory, added:
“Understanding how these bacteria became more virulent and adapted over time is crucial—not just for history, but for anticipating future disease threats. Observing how human societal changes have co-evolved with pathogens offers vital clues about how diseases might evolve going forward. These findings open a window into the intricate relationship between microbes and humans.”
This research not only sheds light on the evolutionary history of infectious diseases but also highlights the powerful synergy between archaeology and genetic science—paving the way for future breakthroughs in understanding human health through time.
