New strains of hepatitis B virus discovered in ancient human remains

The hepatitis B virus has been infecting people since at least the Bronze Age, according to a new study published in the journal Nature. 304 samples of humans from Europe and Asia, who lived between 200 and 7,000 years ago, were examined for hepatitis B DNA. Researchers found matches for the virus in the remains of 25 people, including in the bones of a warrior buried in a mass grave in Mongolia. Some versions of the ancient hepatitis virus still infect humans. Another died out.