HEALTH × GENETICS

The Source of the Black Death

1346 CE

History · Middle Ages · Holocene · Meghalayan

The Black Death killed perhaps half of Europe between 1346 and 1353, and for centuries its origin was a blank on the map. Ancient DNA has now filled it: victims buried in 1338 and 1339 near Lake Issyk-Kul, in modern Kyrgyzstan, under stones naming 'pestilence' as the cause, carried the strain of Yersinia pestis ancestral to the pandemic, closest kin to bacteria still living in local marmot colonies. From that emergence, the germ entered Europe once, and later waves flowed back east to seed the pandemics of the modern era.

Why it matters

This is medicine's cold case closed after seven centuries: a pandemic traced to a decade, a valley and a wild reservoir. The find rearranges the story's moral geography too, the killer was not conjured by filthy cities but spilled from mountains where it still lives today. Every later chapter, from quarantine to modern surveillance of animal reservoirs, descends from what this germ taught.

Dating & uncertainty

The pandemic's arrival in the Mediterranean in 1346 to 1347 is historically documented. What genetics added is the upstream: cemeteries by Lake Issyk-Kul in Kyrgyzstan, with tombstones of 1338 and 1339 naming 'pestilence', held a Yersinia pestis strain that sits at the ancestor node of the pandemic's great diversification, and its closest wild relatives live in marmot reservoirs of the surrounding Tian Shan.

Sources

1. Spyrou et al. (2022), Nature · The source of the Black Death in fourteenth-century central Eurasiadoi:10.1038/s41586-022-04800-3
2. Spyrou et al. (2016), Cell Host & Microbe · Historical Y. pestis genomes reveal the European Black Death as the source of ancient and modern plague pandemicsdoi:10.1016/j.chom.2016.05.012
3. Spyrou et al. (2019), Nature Communications · Phylogeography of the second plague pandemic revealed through analysis of historical Yersinia pestis genomesdoi:10.1038/s41467-019-12154-0

Our species’ history as one day

23:56:533 min 7 s before midnight

if the 315,000 years of Homo sapiens were compressed into a single day