Medieval Manuscripts Reveal 3,700-Year History of Sheeppox Virus

Key points

• University College Dublin researchers detected sheeppox virus DNA in the 1,000-year-old York Gospels, which were written in Canterbury in the late 900s and later housed in York Minster.
• The study, published in Science Advances, analyzed 754 samples from across Eurasia, including sheep bones, parchment, and paper, spanning more than 14,000 years.
• The earliest genetic evidence of sheeppox was found in Bronze Age sheep teeth from Kazakhstan and Russia, dating to approximately 3,700 years ago.
• Viral DNA was unexpectedly found in calfskin and goatskin parchment, suggesting either cross-species infections or contamination during the parchment-making process.
• Sheeppox remains a significant threat today, with recent outbreaks in Greece causing economic damage, despite being eradicated in Europe in the 20th century.

Background

Previous coverage in September 2026 highlighted the recovery of 21 ancient sheeppox genomes from manuscripts and skins, establishing a timeline from 1700 BCE to 1917 CE. Earlier reports noted that the virus's genome has remained relatively stable over millennia, with major divergences from related viruses occurring between 11,500 and 3,700 years ago. This current development expands on those findings by detailing specific manuscript discoveries and the implications for understanding past livestock diseases.

How outlets are covering it

Fox News emphasized the unexpected discovery of virus DNA in the York Gospels, describing the manuscript as a 'biological time capsule' and highlighting the ongoing threat of sheeppox in Greece. The Past website provided a broader historical context, noting that Roman sources from the 1st century AD described similar symptoms, and detailed the screening of 754 samples, with 41 testing positive for Capripoxvirus. University College Dublin researchers, including lead author Louis L'Hôte, focused on the methodological aspect, explaining how parchment preserves DNA and suggesting that archives worldwide may contain similar genetic traces of past disease outbreaks. While Fox News highlighted the stability of the virus genome, The Past noted the medieval peak of the disease and its subsequent resurgence in the 19th century before eradication in Europe.

Why it matters

Understanding the long-term evolution of sheeppox virus helps researchers develop better interventions and predict how pathogens may adapt to new hosts. The discovery that parchment can preserve ancient pathogen DNA opens new avenues for studying historical disease outbreaks and their impact on past societies, particularly those dependent on livestock.

What to watch

Researchers plan to investigate parchments from other regions, such as southern Europe where goatskin was more commonly used, to determine if sheeppox infected other species in the past. Continued study of ancient genomes may provide insights into how the virus evolved and how to combat current and future outbreaks.