Sam Barringer, DVM
WVU Extension Service
Bovine Spongiform Encephalopathy, or BSE, is the appropriate name of a fatal brain disease known to exist in beef and dairy cattle in the United Kingdom (the UK includes England, Scotland, Ireland, Wales). In the UK, the disease was given the inappropriate name "Mad Cow Disease," a label which has been perpetuated by the media worldwide. The cows infected with BSE are not "mad" and some researchers have said a more appropriate name might be "Sad Cow Disease" because the loss of muscular coordination and locomotive function caused by BSE is, indeed, a sad thing to observe.
Fortunately, we do not have BSE in the United States or Canada. Efforts are underway to fully understand why the disease became such a problem in the UK. This information will help ensure we never acquire BSE here. The following provides answers to a set of commonly asked questions regarding BSE. The responses are based on the review of the scientific literature and direct communication with scientists studying this problem.
What is BSE? BSE is an extremely rare, chronic degenerative disease affecting the central nervous system of cattle. BSE is not present in the U.S., but has been identified in the United Kingdom and in a few other countries.
What are the symptoms of BSE? Cattle with BSE have coordination problems and are very nervous. In the advanced stages, infected cattle stand away from the rest of the herd and exhibit severe muscular twitching and weight loss.
Where was BSE first detected? BSE was first identified in 1986 in Great Britain. While it has been found in a few other countries, the vast majority of BSE cases have been concentrated in the United Kingdom.
How do cattle get BSE? Scientists think that cattle may get the disease from eating protein in feed that was probably contaminated with a spongiform disease agent.
Has BSE ever been detected in the U.S.? No cases of BSE have been detected in the U.S. In fact, over the last several years, USDA has conducted 2,660 tests on brains from cattle that have shown any possible neurological symptoms. All tests were negative.
Can you get BSE from eating beef? No. Scientific evidence indicates that BSE cannot be transmitted from infected cattle to humans through physical contact or consumption of beef or dairy products. The World Health Organization does not consider BSE to be a human health hazard based on current scientific evidence.
Some people in Great Britain think that you can get Creutzfeldt-Jakob Disease (CJD), a human brain disease, from eating beef from cattle with BSE. Is that true? Experts in Great Britain are concerned there may be a link between BSE and a small group (10 cases) of CJD. If there is a risk, it would be linked to consumption of brain or spinal cord from infected cattle. Scientific evidence indicates that beef (meat) and milk do not present a risk to people as there is no evidence the agent that causes BSE is present in meat and milk.
Can animals get BSE from physical contact with each other? No. Scientific evidence indicates that BSE does not spread from cattle to cattle or from cattle to other species by physical contact.
Is BSE a virus or a bacterial infection? The scientific evidence suggests that BSE is not a viral or bacterial infection. Rather, it seems to point to a protein material or "prion" as the cause of the disease.
How widespread is BSE and what has the British government done to
control its spread? Between 1986 and September 1995, an estimated 156,000 head of cattle
in more than 32,000 herds were diagnosed with BSE in Great Britain. The number of cases
peaked in December 1992, has declined to less than one-third of that rate and is still
A series of precautionary steps taken in Great Britain has resulted in the decline in newly reported cases. For example, in July 1988, Great Britain banned the feeding of ruminant-derived protein to ruminants. In addition, Britain made BSE a notifiable disease and all animals showing signs of BSE are destroyed. Currently, fewer than 300 cases are occurring per week.
What steps has USDA taken to prevent BSE from entering the U.S.? To prevent BSE from entering the United States, USDA's Animal and Plant Health Inspection Service (APHIS) has taken the following steps:
- Beginning in 1989, APHIS banned the importation of live ruminants and ruminant products from countries where BSE is known to exist.
- Since 1991, there has been a voluntary ban in place on the use of rendered products from adult sheep in animal feeds.
- In 1986, APHIS established a program for BSE surveillance in the U.S. and provided specialized training for 250 APHIS veterinarians who conduct field investigations involving animals with any suspicious symptoms.
- APHIS veterinary pathologists and field investigators have received training from British counterparts for diagnosing BSE.
- More than 60 veterinary diagnostic laboratories throughout the United States are participating in the BSE Surveillance Program (initiated in May 1990) along with the National Veterinary Services Laboratories in Ames, IA.
- APHIS veterinarians are tracing 499 head of cattle imported from Great Britain between 1981 and 1989 (before the ban on imports went into effect) to check their health status. As of January 22, 1996, 116 imports are known to be alive; 341 are known to be dead; and eight imports have been exported. APHIS is trying to locate the remaining 34, but based on the age of the animals, they are assumed to be dead. The animals that are alive are monitored regularly, and no signs of BSE have been found.
- From 1986 to December 31, 1995, 2,660 brain specimens from cattle exhibiting possible neurological problems in 42 states had been studied by APHIS. All samples submitted have been negative.
"Creutzfeldt-Jakob Disease, Assessment and Management," Journal of Gerontological Nursing, November 1993, pp. 15-22.
"The Transmissible Spongiform Encephalopathies," Annual Review of Medicine, 1995, 46: pp. 57-65.
"Genetic Predisposition to Iatragenic Creutzfeldt-Jakob Disease," 1991, Lancet, 337: pp. 1141-1142.
"Greutzfeldt-Jakob Disease Associated With PRNP Codon 200 LYS Mutation: An Analysis of 45 Families," European Journal of Epidemiology, 1991, Issue 7, pp. 477-86.
"The Prion Diseases," Scientific American, January 1995, pp. 48-57.
"Fact Sheet, Bovine Spongiform Encephalopathy," U.S. Department of Agriculture, Animal and Plant Health Inspection Service, February 1996.
Dr. Will Hueston
Animal and Plant Health Inspection Service,
Veterinary Service Unit 33, 4700 River RoadRiverdale,
Phone: 301/734-8093; Fax: 301/734-8818
Dr. Harley Moon
Plum Island Animal Disease Center
USDA Agricultural Research Service
Greenport, NY 11944
Phone: 516/323-2500, ext. 207; Fax: 516/323-2507