A total of 231 cases of vCJD have been reported since it was first discovered. These cases have been found in a total of 12 countries with 178 in the United Kingdom, 27 in France, five in Spain, four in Ireland, four in the United States, three in the Netherlands, three in Italy, two in Portugal, two in Canada, and one each in Japan, Saudi Arabia, and Taiwan. History
In the 5th century BCE, Hippocrates described a disease like TSE in cattle and sheep, which he believed also occurred in man. Publius Flavius Vegetius Renatus records cases of a disease with similar characteristics in the 4th and 5th centuries AD. In 1755, an outbreak of scrapie was discussed in the British House of Commons and may have been present in Britain for some time before that. Although there were unsupported claims in 1759 that the disease was contagious, in general it was thought to be due to inbreeding and countermeasures appeared to be successful. Early-20th-century experiments failed to show transmission of scrapie between animals, until extraordinary measures were taken such as the intra-ocular injection of infected nervous tissue. No direct link between scrapie and disease in man was suspected then or has been found since. TSE was first described in man by Alfons Maria Jakob in 1921. Daniel Carleton Gajduseks discovery that Kuru was transmitted by cannibalism accompanied by the finding of scrapie-like lesions in the brains of Kuru victims strongly suggested an infectious basis to TSE.
Transmissible spongiform encephalopathies (TSEs) are a group of progressive and fatal conditions that are associated with prions and affect the brain and nervous system of many animals, including humans, cattle, and sheep. According to the most widespread hypothesis, they are transmitted by prions, though some other data suggest an involvement of a Spiroplasma infection. Mental and physical abilities deteriorate and many tiny holes appear in the cortex causing it to appear like a sponge when brain tissue obtained at autopsy is examined under a microscope. The disorders cause impairment of brain function, including memory changes, personality changes and problems with movement that worsen chronically.TSEs of humans include Creutzfeldt–Jakob disease, Gerstmann–Sträussler–Scheinker syndrome, fatal familial insomnia, kuru, as well as the recently discovered variably protease-sensitive prionopathy and familial spongiform encephalopathy. Creutzfeldt-Jakob disease itself has four main forms, the sporadic (sCJD), the hereditary/familial (fCJD), the iatrogenic (iCJD) and the variant form (vCJD). These conditions form a spectrum of diseases with overlapping signs and symptoms. TSEs in non-human mammals include scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle – popularly known as "mad cow disease" – and chronic wasting disease (CWD) in deer and elk. The variant form of Creutzfeldt–Jakob disease in humans is caused by exposure to bovine spongiform encephalopathy prions.Unlike other kinds of infectious disease, which are spread by agents with a DNA or RNA genome (such as virus or bacteria), the infectious agent in TSEs is believed to be a prion, thus being composed solely of protein material.