|Fact sheet No 180: Variant Creutzfeldt-Jakob disease (vCJD) - Revised December 2000 (WHO, 2000, 4 p.)|
Revised December 2000
Variant Creutzfeldt-Jakob disease (vCJD) is a rare and fatal human neuro-degenerative condition. Like Creutzfeldt-Jakob disease (CJD), vCJD is classified as a transmissible spongiform encephalopathy (TSE) because of characteristic spongy degeneration of the brain and its ability to be transmitted. vCJD is a new disease which was first described in March 1996.
Prior to the identification of vCJD, CJD was recognized to exist in only three forms. Sporadic cases, which have an unknown cause and occur throughout the world at the rate of about one per million people, account for 85-90% of CJD cases. Familial cases are associated with a gene mutation and make up 5-10% of all CJD cases. Iatrogenic cases result from the accidental transmission of the causative agent via contaminated surgical equipment or as a result of cornea or dura mater transplants or the administration of human-derived pituitary growth hormones. Less than 5% of CJD cases are iatrogenic.
In contrast to the traditional forms of CJD, vCJD has affected younger patients (average age 29 years, as opposed to 65 years), has a relatively longer duration of illness (median of 14 months as opposed to 4.5 months) and is strongly linked to exposure, probably through food, to a TSE of cattle called Bovine Spongiform Encephalopathy (BSE).