Plague persisted in Europe for longer than thought

The bacteria that causes plague, Yersinia pestis, may have persisted long-term in Europe from the 14th to 17th century in an unknown reservoir, according to a study.

Some researchers suggest that it may have been a result of a viral disease. However, the most recent research on ancient plague reveals that the deadly disease existed thousands of years earlier than previously thought.

In addition to the assumed continuous re-introduction of Y pestis from central Asia in multiple waves during the second pandemic, it's also possible that Y pestis persisted long-term in Europe in a yet unknown reservoir host, said lead author Lisa Seifert from the Ludwig Maximilian University of Munich in Germany.

In the study, researchers recovered and analysed ancient DNA from 30 plague victims of the second plague pandemic.

They were excavated from two different burial sites in Germany, and spanning more than 300 years.

Of the 30 skeletons tested, eight were positive for Yersinia pestis-specific nucleic acid.

All positive individuals genetic material were highly similar to previously investigated plague victims from other European countries and had identical Y pestis genotype.

The study was published in the journal PLOS ONE.