Ancient parchments reveal 3,700-year saga of the sheeppox virus

Ancient DNA extracted from medieval parchments and Bronze Age sheep remains shows the sheeppox virus (SPPV) spanning about 3,700 years, with 21 new ancient genomes recovered from manuscripts and skins. The findings suggest skins from infected animals were used for parchment, linking the virus’s history to sheep domestication and Eurasian livestock movements, while genetic analyses indicate long-term stability of the SPPV lineage (with major divergences dating back 11,500–3,700 years). The research underscores how parchment preserves a record of livestock disease that still poses risks today, reflected in contemporary outbreaks.