Ancient Sheeppox Virus DNA Unearthed from Medieval Parchment Reveals 3,500‑Year Evolution

Sheeppox Virus Traced Back 3,500 Years Through Parchment DNA

The sheeppox virus that once ravaged European flocks is now emerging from an unlikely archive: the skins that formed medieval manuscripts. By extracting DNA from centuries‑old parchment, researchers reconstructed viral genomes that span 3,500 years, revealing a continuous lineage of the pathogen.

A team led by University College Dublin’s Louis L’Hôte sequenced fragments preserved in animal skins, publishing their findings in Science Advances. Their work shows that libraries could harbor hidden genetic records of past animal epidemics.

Historical texts first mention sheeppox‑like lesions in the first‑century CE, with medieval agricultural manuals repeatedly citing “pockes” in sheep across France, Spain and England. Outbreaks waned in 17th‑century France, only to surge again in the 18th and 19th centuries, when mortality spikes were recorded. By the 20th century, coordinated eradication efforts drove incidence ↓ 70%, yet regional flare‑ups, such as the 2023 Greek episode reported by Reuters, persist.

“Ancient pathogen DNA reshapes our grasp of disease history; parchment proves to be an unexpected reservoir,” L’Hôte remarked.