Second plague pandemic

Plague epidemic recorded near Lake Issyk-Kul

A 1338 tombstone says a believer called Sanmaq 'died of pestilence'. Ancient DNA from three sampled people in the same cemetery confirmed Yersinia pestis in the local epidemic.

Three positives out of seven

A mortality crisis struck the Christian community buried at Kara-Djigach and nearby Burana, in the Chüy Valley of present-day Kyrgyzstan, across 1338 and 1339. Ten East Syriac tombstones at Kara-Djigach say outright that the buried person died of pestilence.

Researchers sampled seven individuals — five from Kara-Djigach, two from Burana — and found evidence of Yersinia pestis in three, all from Kara-Djigach. Two high-quality genomes were reconstructed, representing a single strain.

What the genomes place, and what they do not

That strain sits as the most recent common ancestor of the major Y. pestis diversification associated with the second plague pandemic. Comparison with modern plague diversity supports emergence somewhere in central Eurasia, possibly the extended Tian Shan region.

It does not prove the bacterium first evolved inside these cemeteries. Saying a strain originates in 1338 is stronger than the evidence allows: this is an epidemic documented across two years by inscriptions and burial distribution, not a datable event.

The blank between here and Crimea

The researchers found no evidence identifying the environmental trigger, the animal host, or the route of introduction into the community. The narrow sampling cannot reconstruct where the strain travelled next.

Of the 467 surviving dated tombstones in the study dataset, 456 come from Kara-Djigach and 11 from Burana; a separate study counts 118 of the 159 headstones erected between 1338 and 1345 as belonging to the mortality crisis. What happened between the Chüy Valley and the Black Sea remains unknown.

Sources

Researched 23 Aug 2026 5 sources 3 audit passes, 1 issue open Date disputed

How this was checked

Researched from the web into a fact sheet, rewritten from that sheet, then audited against it by a different model. How the pipeline works →

Date disputed. Sources disagree; the research places it at ~1338.

What the sources leave uncertain

This is not a datable one-day event. The inscriptions and burial distribution document an epidemic spanning 1338–1339.
The title’s assertion that a strain “originates” in 1338 is stronger than the evidence. The genomes support a central-Eurasian or extended-Tian-Shan source for the second pandemic, not an observed evolutionary event on a specific day or at a specific graveyard.
The study’s narrow sampling cannot reconstruct the strain’s geographic spread, and the exact route to the western Eurasian outbreaks remains unknown.