Historical Narrative
The earliest unambiguous written descriptions of scrapie in sheep appear in English and German agricultural literature of the early eighteenth century, with a 1732 report to the British House of Commons representing one of the most frequently cited documentary landmarks. British wool farmers and their Continental counterparts had likely observed the condition for considerably longer, but formal written records from earlier periods remained sparse and difficult to distinguish from descriptions of other livestock ailments.
Eighteenth and nineteenth century veterinary and agricultural writers described the disease as a wasting condition of sheep that progressed over months and invariably ended in the animal's death. Farmers in Britain gave it names such as the rubbers, the rickets, and the goggles, each term reflecting a different observable aspect of the afflicted animals' behavior. German-speaking regions developed their own vernacular terminology, and French veterinarians wrote of la tremblante, the trembling disease, a name that captured the involuntary shaking many affected animals displayed in later stages.
Early theories about causation ranged widely. Some eighteenth-century agricultural writers attributed scrapie to wet pastures or mineral deficiencies in the soil. Others suspected hereditary weakness, and the observation that certain bloodlines appeared more susceptible gave this hereditary hypothesis considerable staying power well into the twentieth century. The French veterinarian Tessier, writing in the late eighteenth century, was among the first to argue systematically about the disease's nature, though his conclusions remained inconclusive by later standards.
The question of contagion became a matter of serious scientific debate in the early twentieth century. In 1936, French researchers Jean Cuillé and Paul-Louis Chelle demonstrated through careful experimental work that scrapie could be transmitted from an affected sheep to a healthy one by inoculation of neural tissue, establishing for the first time that an infectious agent was involved. This finding was a watershed moment, though the nature of that agent remained deeply obscure.
British veterinary researchers, particularly William Gordon working at the Moredun Research Institute in Edinburgh during the mid-twentieth century, conducted extensive studies into scrapie's transmission properties and incubation periods. Gordon's work, along with that of colleagues including Richard Chandler, helped characterize scrapie as what researchers began calling a slow virus infection, a conceptual category that also came to include certain human neurological diseases.
The connection between scrapie and human medicine became electrifying when American physician and virologist Daniel Carleton Gajdusek demonstrated in the 1960s that kuru, a fatal neurological disease observed among the Fore people of Papua New Guinea, could be transmitted to chimpanzees in a manner resembling scrapie transmission. Gajdusek's work, for which he received the Nobel Prize in Physiology or Medicine in 1976, drew a conceptual line between animal and human slow infections that fundamentally changed how scientists thought about neurological disease.
The most radical reinterpretation of scrapie came from American biochemist Stanley Prusiner, who proposed in the early 1980s that the infectious agent was an abnormally folded protein he named a prion, containing no nucleic acid. This hypothesis overturned foundational assumptions about how infectious disease worked and was met with intense skepticism before accumulating evidence transformed it into scientific consensus. Prusiner received the Nobel Prize in Physiology or Medicine in 1997, and scrapie's long history as an agricultural nuisance had by then become inseparable from one of the most consequential discoveries in the history of biology.
Key Historical Figures
Historical narrative only — this page describes how Scrapie was understood historically. It is not medical advice and does not describe current diagnosis or treatment. Sourced from verified medical history references (NIH, Encyclopaedia Britannica, and standard medical history texts). See our medical disclaimer.