Ancient Siberian plague outbreaks traced to Lake Baikal hunter-gatherers via ancient DNA

A Nature study of ancient DNA from 46 individuals buried near Lake Baikal reveals two previously unknown Yersinia pestis strains, indicating two plague outbreaks about 5,600–5,300 and 5,100–4,900 years ago among hunter-gatherers. About 40% of the individuals carried plague DNA, suggesting significant mortality in small communities likely caused by pneumonic plague transmitted person-to-person; marmots may have been the reservoir. This pushes plague's emergence far earlier than previously thought and shows epidemics affected hunter-gatherer groups before farming communities appeared.