The Role of Beef in the American Diet - International Meat Secretariat

The Role of Beef in the American Diet
encephalopathies. The best known of these is Creutzfeldt–Jakob disease
(CJD), a fatal neurological disorder that occurs sporadically, affecting
about one person in a million, almost always older people.
A major outbreak of BSE began in the United Kingdom in the mid-
1980s. By the year 2000, approximately 200,000 cases of BSE had
occurred in British cattle (69); the epidemic peaked in the early 1990s,
and the number of cases decreased sharply thereafter due to the imposition
of stringent control measures including the destruction of millions
of suspect animals. Cases of BSE have occurred in other countries as
well, primarily in Europe. However, it is important to emphasize that an
active surveillance program in the U.S. has not detected any cases here (70).
Scientists are not certain of the origin of BSE in Britain, but they do
know that once it appeared, it was spread by the practice of including
protein nutritional supplements derived from cattle in the feed given to
young calves. An ordinary viral or bacterial disease would not spread in
this way, since the disease agent would be killed by the heat used in
processing the animal feed supplement. But prions can survive.
At first, it was thought likely that BSE was only a threat to cattle,
just as scrapie is only a threat to sheep. However, in the mid-1990s, a
few cases began to be reported in Britain of a fatal human disease that
resembled CJD, but with some unusual features: the initial symptoms
were different, the course of the disease was slower, and most of the
patients were atypically young for CJD. As of April 2002, about 125
cases of this disease, now called variant CJD (vCJD) or new variant
CJD (nvCJD), had been reported worldwide (71), all in people who had
lived in countries where BSE exists, primarily the U.K. One probable
case has been reported in the U.S., in a British citizen who was living in
Florida at the time of diagnosis (72), and one case has been reported in
Canada, in an individual who had spent extensive time in the U.K. at
the height of the BSE epidemic (73). Both patients are believed to have
contracted the disease in the U.K. There is strong epidemiologic and
laboratory evidence linking vCJD with BSE (69). It is now believed that
the two diseases are caused by the same agent.
Experts believe that most of the people who have contracted vCJD
acquired the disease by consuming cattle products that contained central
nervous system tissue contaminated with the BSE agent (71). Exposure
probably occurred through consumption of ground or processed meat
products that inadvertently contained small amounts of nervous system
tissue.
The U.S. government has taken multiple precautions to keep BSE out
of the U.S. Three of the most important precautions are the following:
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