"Mad Cow Disease" Fact Sheet

What is Mad Cow Disease
[Bovine Spongiform Encephalopathy/ BSE]?
"Mad Cow" disease is the commonly used name for Bovine Spongiform Encephalopathy [BSE], a slowly progressive, degenerative, fatal disease affecting the central nervous system of adult cattle. BSE was first reported in cattle in the United Kingdom in November 1986, which resulted in the massive slaughter of infected and potentially infected cattle. Scientists believe cattle are infected with BSE when they consume feed that contains remnants of infected animals. Affected animals may display changes in temperament, such as nervousness or aggression, abnormal posture, coordination problems, difficulty walking, decreased milk production, severe muscle twitching and loss of weight despite regular appetite. In cattle that have BSE, about 98 percent of infection is found in the brain, spinal cord, and eye. Infectious material has not been detected in muscle tissue or milk. There is no treatment for BSE and affected cattle die.

Has BSE Been Identified in the U.S.?
In December 23, 2003, "Mad Cow" disease was discovered in a single dairy cow imported from Canada in Washington State. Because the cow was born in Canada before it was illegal to feed animal protein back to cattle, the cow may have been exposed to the disease through eating contaminated feed. Since the discovery of BSE in the U.S., the United States Department of Agriculture [USDA] immediately recalled meat. Meat that did enter the food supply was traced and removed from the marketplace. Moreover, all the cattle’s infected organs were removed at slaughter and did not enter the food supply. Since 1989, the Food and Drug Administration [FDA] and other federal agencies have had ongoing regulatory measures in place to prevent BSE contamination of U.S. food and food products. Following the identification the Washington state BSE-positive cow, the USDA has issued four new regulations containing additional safeguards to further minimize risk for introduction of the BSE agent into the food supply. Their safeguards include:

• Bans on use of live, non-ambulatory cattle from entering the human food supply.
• Bans on use of organs, from cattle older than 30 months, in which infectious prions occur.
• Restrictions on techniques to mechanically remove meat from bones.
• Meat from tested animals will not be certified as USDA-inspected until test results are final.

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What Causes BSE?
The exact cause of BSE is not known; however, scientists believe that infectious forms of a type of protein, prions, normally found in animals cause BSE. The abnormal protein triggers a chain-reaction causing other proteins in the brain to change to the abnormal form. These abnormal proteins accumulate in the brain converting normal prions to abnormal ones, which results in unstable behavior and eventually death. In cattle with BSE, these abnormal prions initially occur in the small intestine, tonsils, and found in central nervous tissue, such as the brain and spinal cord. Muscle meat is not a source of infectious prions. Traditional methods to destroy microbes do not work on prions. The prion protein can survive extremely high temperatures; therefore, cooking will not protect anyone from this abnormal prion protein.

Is BSE Dangerous to Humans?

Evidence shows a relationship between the cattle BSE, or Mad Cow disease, and the human disease Creutzfeldt-Jakob disease [CJD], a rare, naturally occurring brain disease characterized by progressive dementia [memory loss] and death. In 1996, following outbreaks of BSE among British cattle, scientists found a possible link of a new variant of CJD [vCJD]. Scientists believe that humans may acquire vCJD after consuming BSE-contaminated cattle products. The new vCJD is a rare, degenerative, fatal brain disorder in humans. Experience with this disease is limited. Evidence to date indicates that there has never been a case of vCJD transmitted through direct contact of one person with another. However, a case of probable transmission of vCJD through transfusion of blood components from an asymptomatic donor who subsequently developed the disease has been reported. There is no treatment of vCJD and it is invariably fatal.

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What are the Symptoms of vCJD
The symptoms of vCJD include: depression; "stickiness" of the skin; difficulty walking and involuntary movements. Patients become completely immobile and mute before death. The incubation period for vCJD is unknown because it is a new disease. However, scientists believe that the incubation period may be measured in terms of many years or decades. In other words, wherever a person develops vCJD from consuming a BSE-contaminated product, he or she likely would have consumed that product many years or a decade or more earlier.

As of December 1, 2003, a total of 153 cases of vCJD has been reported in the world: United Kingdom [143]; France [6]; Canada [1]; Ireland [1]; Italy [1] and United States [1]. The U.S. case was reported in a patient who lived in the United Kingdom before moving to the United States.

Michigan BSE Prevention Measures
Michigan is an active partner with the USDA and the FDA in efforts to help ensure that the state and country are actively and aggressively working to prevent BSE, and to respond quickly and appropriately if detected. The Michigan Department of Agriculture [MDA] has indicated that there is no reason to question the safety of Michigan’s or U.S. beef supply due to BSE:

• MDA annually inspects Michigan’s feed manufacturers and retailers to ensure that Michigan cattle are eating only FDA-approved feed. Since 1999, 900 inspections have been conducted and nearly 100% compliance has been found.
• MDA is in regular contact with agricultural industry stakeholders to help ensure education and outreach. The department will host a meeting with the animal feed industry, producers, and farm organizations to share information and ensure that the state is doing everything it can to prevent BSE.
• MDA’s veterinarians have reviewed all import records of animals coming into Michigan, Canada, Washington State and Idaho, and are conducting tracebacks to determine final or current disposition of animals.

Michigan’s Cattle Industry

• Michigan is home to 990,000 head of cattle (beef and dairy), which are raised on about 15,500 farm operations throughout the state.
• The beef and dairy cattle industry is very important part of Michigan’s overall agricultural economy with an annual value of more than $870 million. The state ranks 31st in terms of animal production/ numbers and 7th-8th in terms of diary/milk production/value.
• Michigan produces approximately 425 million pounds of beef each year worth over $200 million [actual cash receipts from cattle and calf marketing].

Sources: National Centers for Disease Control and Prevention; U. S. Food and Drug Administration; World Health Organization and the Michigan Department of Agriculture

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