What is "Mad Cow Disease"?
"Mad Cow Disease" is a nickname for a livestock disease called Bovine Spongiform Encephalopathy (BSE). The disease has afflicted cattle in a number of countries around the world, and recently one cow in the United States. As of the announcement by the Agriculture Secretary, Ann M. Veneman, on December 23, 2003, the disease has been found in one cow located in Washington State. BSE is a degenerative neurological animal disease caused by an aberrant protein called a prion. It is in the family of diseases - all caused by prions - referred to as transmissible spongiform encephalopathies, or TSEs. Spongiform comes from the fact that the brain takes on the structure of a sponge. Encephalopathies are diseases of the brain. TSEs include scrapie in sheep and goats, chronic wasting disease (CWD) in deer and elk, and Creutzfeldt-Jakob disease, or CJD, in humans. It's important to note that TSEs are not communicable diseases - they do not spread easily like viruses. TSE's are diseases of the central nervous system and slowly cause its failure. All have long incubation periods lasting from months to years. There is no cure and they are always fatal.
What Caused BSE?
The exact cause of BSE is unknown, but the leading scientific theory suggests that BSE was likely caused in U.K. cattle as a result of feed made from infected cattle protein. A common practice, which has been banned since August of 1997, resulted in the feeding of proteins from infected cattle to other ruminant animals (e.g. cattle). Since the infected cow found in Washington State was approximately 6Â 1/2 years old, she would have been born before feed bans were implemented, and therefore feed may have been the avenue for the disease to occur.
Is Beef Safe to Eat?
United States beef is safe! The scientific community believes that there is no evidence to demonstrate that muscle cuts (i.e. steaks), whole muscle meats (i.e. roasts), or meat products (i.e. ground beef, sausages, etc.) that come from animals infected with BSE are at risk of harboring the causative agent of the disease.
The agents responsible for BSE are found in neurological tissues like the brain and spinal cords. Spinal cords are not meat and may not be added to meat products. Brains may be sold for consumption, but are not commonly consumed by the American population. Brains are not added to processed meat products such as hot dogs and other sausages as an ingredient. Furthermore, since these materials are not considered as meat by the USDA, if they were used, they would have to be declared in the ingredient statement of the product.
BSE and Implications for Humans
BSE is an animal disease that affects cattle. However, other TSEs affect humans. Scientific evidence supports a causal relationship between BSE outbreaks in Europe and another TSE disease in humans, called new variant Creutzfeldt-Jakob Disease (vCJD). However, scientists believe that it is not easy to contract vCJD.
Early in the BSE epidemic in the United Kingdom, when little was understood about the disease, U.K. citizens routinely consumed beef brains in a variety of British dishes. It has been reported that the increase in vCJD cases occurred due to the diets of the victims. In fact, the world's leading experts believe those who developed vCJD probably had a certain genetic predisposition that was triggered by such high levels of exposure to the BSE agent. While 183,000 cases of BSE have been diagnosed in U.K. cattle, less than 150 cases of vCJD have been diagnosed.
Background on BSE
The following are some points to remember regarding BSE:
- BSE is an animal disease issue, not a food safety issue
- Meat from the carcass of the cow is low-risk, as BSE is not known to be carried in the muscle tissue
- Beef muscle cuts are safe to eat, even from countries with a high prevalence / high risk of BSE
- Officials reconfirmed that there is a virtual zero risk to humans who consume the muscle meat from an infected animal, and the meat recall was taken in an abundance of caution
- The safety and wholesomeness of beef is mainly due to rigid inspection procedures and new food safety technologies
- BSE does not affect the lactation system, therefore milk and dairy products are considered safe and have not been shown to be carriers of the infectious BSE prion protein
- Transmission of BSE from a cow to her offspring is rare
- USDA testing offers a statistically sound 95% confidence level of detecting a one in a million case of BSE
- The term "downer" is a generic term used to decribe all injuried cattle, including but not limited to those with broken appendages, severed tendons or ligaments, factured vertebral column or metabolic conditions
- By and large, non-ambulatory cattle are such due to recent injuries or localized injuries (i.e. broken appendages), in which the meat has traditionally been considered safe and wholesome
- BSE is predominantly a disease of older animals, mostly cattle 3-6 years of age
- There is no recognized BSE test, at this time, for live cattle
Keep Potential Health Risks in Perspective
(Written by Dr. Knipe and Dr. Shulaw, Ohio State University)
It is important to keep potential health risks in perspective. For comparison, as of June 3, 2003, 770 deaths from SARS have been reported to the WHO - a disease just recognized this year; a May 5, 2003 article in the online version of USA Today reports that annually about 70 people are killed from lightning strikes in the United States*; each year in the United States about 90 to 100 people die of bee stings ( http:// ohioline.osu.edu/ hyg-fact/ 2000/ 2076.html ); and in an article in the journal, The Physicians and Sportsmedicine** researchers reported that during the years of 1987-1996 there were more than 29,000 injuries in Little League Baseball players aged 5 to 12 years. About 25 percent of these were considered serious, and 13 players died.
* ( www.usataoday.com/ weather/ resourcesbasics/ wlightning.htm )
** Vol. 29 No7 July, 2001, www.physsportsmed.com/ issues/ 2001/ 07_01/ mueller.htm
Certainly it is appropriate to strive for zero risk in our food supply, but we must realize that zero is often unattainable. The available evidence suggests that the risk to the consumer of BSE in our American beef supply is very minimal.
Further Information
For more information on Bovine Spongiform Encephalopathy (BSE) and to follow the progress of the U.S. BSE investigation, visit the following websites:
- American Association of Meat Processors
www.aamp.com
- National Cattlemen's Beef Association
www.bseinfo.org
- United States Department of Agriculture
www.usda.gov
- USDA Meat and Poultry Hotline
1-888-674-6854
Email: mphotline.fsis@usda.gov
This product was added to our catalog on Wednesday 27 April, 2005.