The plague bacterium Yersinia pestis may have lurked in a medieval European reservoir for at least 300 years, researchers from Germany suggest January 13 in PLOS ONE.
The second of two major plague pandemics hit Europe from the 14th to 17th centuries. The new study weighs in on a long-standing debate over what fed the pandemic: strains of the bacterium traveling along with trade from Asia via the Silk Road or a homegrown biological reservoir such as lice.
The team analyzed DNA from 30 skeletons dating to the 14th to 17th centuries. Five had strains of Y. pestis that could be analyzed; all strains bore genetic similarity to each other and to strains previously found in European plague victims. Strains from Asia would have injected more genetic variety. Instead, the results suggest that at least one Y. pestis strain sparked the outbreak in Europe and stuck around for a long time.