BSE (“Mad Cow Disease”) and vCJD
“Mad Cow Disease” actually refers to bovine spongiform encephalopathy (BSE), a disease first described in 1996 - in cattle, which is related to a disease in humans called variant Creutzfeldt-Jakob disease (vCJD). Both disorders are fatal brain diseases caused by a prion - a protein particle that lacks nucleic acid and is believed to be the cause of various infectious diseases of the nervous system. The link between the agent that causes human deaths from vCJD and outbreaks of BSE in cattle appears to be dietary consumption of infected beef.
Non-variant forms of Creutzfeldt-Jakob disease (CJD), which existed before 1996, still exist and may have one of three causes: unknown; caused by a genetic mutation; or caused by contaminants introduced during a medical procedure (conventional sterilization methods may not remove the prion which transmits the infection). According to the World Health Organization (WHO), less than five percent of non-variant CJD cases are introduced through medical procedures.
What is bovine spongiform encephalopathy (Mad Cow Disease)?
BSE is a progressive neurological disorder of cattle resulting from infection by a prion. By September 2006, 196 human cases of VCD were reported in the United Kingdom and seven in other countries.
In addition to the cases of BSE reported in the United Kingdom (83 percent of all cases were reported there), cases have also been reported in other countries, including Belgium, France, Liechtenstein, Luxembourg, Netherlands, Portugal, Ireland, Italy, Switzerland, Canada, and the United States. Public health control measures have been implemented in each country of Europe to prevent potentially BSE-infected tissues from entering the human food chain. These preventative measures appear to have been effective. Other countries reporting a rare number of cases of BSE include Japan, Greece, and Finland.
What is variant Creutzfeldt-Jakob Disease (vCJD)?
Creutzfeldt-Jakob Disease (CJD) is a rare, fatal, brain disorder that causes a rapid, progressive dementia (deterioration of mental functions) as well as associated neuromuscular disturbances. The disease, which, in some ways resembles BSE, traditionally has affected men and women between the ages of 50 and 75 years. The variant form, however, affects younger persons (the median age of onset is 28 years) and has atypical clinical features as compared to CJD.
What is the current risk of acquiring vCJD from eating beef and beef products produced from cattle in Europe?
Currently this risk appears to be very small - perhaps fewer than one case per 10 billion servings - if the risk exists at all. Travelers to Europe who are concerned about reducing any risk of exposure can avoid beef and beef products altogether, or can select beef or beef products, such as solid pieces of muscle meat, as opposed to ground beef and sausages. The solid pieces of beef have a reduced opportunity for contamination with tissues that may harbor the BSE agent. Milk and milk products are not believed to transmit the BSE agent. Consult your physician for more information.