Scientists have traced a plague epidemic to hunter‑gatherer communities in southeastern Siberia around 5,500 years ago, after detecting Yersinia pestis DNA in the teeth of dozens of victims. The bacterial signatures were recovered from four burial sites near Russia’s Lake Baikal, providing the earliest direct evidence of plague in humans.
The research was carried out by Ruairidh Macleod and colleagues at the University of Oxford, who sequenced the pathogen’s genome from the ancient remains. The strain they identified is the oldest Y. pestis genome recovered to date, predating previous estimates that linked the disease’s emergence to the rise of agriculture and urban living.
These results overturn the long‑standing hypothesis that plague only became a major threat once people settled in crowded farms with rats. Instead, the study shows that nomadic groups were already susceptible to deadly infections. Further archaeological sampling may reveal additional early cases and clarify the pathogen’s evolutionary path.
