The plague was causing deadly outbreaks among communities of hunter-gatherers in Siberia around 5,500 years ago, according to a study on Wednesday that sheds light on how humans could have first caught this scourge.
The plague is generally associated with rats spreading the disease through crowded mediaeval cities, sparking pandemics such as the Black Death that killed tens of millions of people across Europe from the 1300s to 1800s.
