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• Prohibiting importation of live ruminant animals and most ruminant products from all of Europe (USDA)

• Examining U.S. cattle exhibiting abnormal neurological behavior to test for BSE (USDA)

• Prohibiting the use of most mammalian protein in the manufacture of animal feeds given to ruminant animals (FDA)

• Recommending that animal tissues used in drug products should not come from a country with BSE (FDA)

• Issuing guidelines asking blood centers to exclude potential donors who have spent six or more cumulative months in the U.K. between 1980 and 1996 from donating blood (FDA)

• Conducting regular surveillance for any cases of vCJD among humans (CDC)

• Conducting research on BSE, CJD, vCJD and related neurological diseases (NIH)

BACKGROUND ON BSE AND vCJD

BSE (sometimes referred to as "mad cow disease") and variant and classic CJD belong to the unusual group of progressive, degenerative neurological diseases known as transmissible spongiform encephalopathies (TSEs). These diseases are characterized by a long incubation period of up to several years, during which there is no visible indication of the disease. The incubation period for BSE among cattle ranges from three to eight years; for vCJD among humans, the incubation period is unknown, but is at least five years and could extend up to 20 years or longer. The diseases are invariably fatal; there is no known treatment or cure.

It is believed that vCJD may be acquired from eating food products containing the BSE agent, and there is strong epidemiologic and laboratory evidence for a causal association between vCJD and BSE. The absence of confirmed cases of vCJD in geographic areas free of BSE supports a causal association. BSE and vCJD have never been identified in the United States.

BSE among cattle was first described in the U.K. in November 1986. Epidemiological evidence established that the outbreak of BSE was related to the production and use over many years of contaminated meat-and-bone meal. The source of the BSE outbreak is uncertain. There is strong evidence and general agreement that the outbreak was amplified by feeding rendered bovine meat-and-bone meal to young calves.

The vast majority of BSE cases have been reported in the U.K. Through November 2000, about 177,500 cases of BSE have been confirmed there in more than 35,000 herds of cattle. The U.K. epidemic peaked in January 1993 at nearly 1,000 new cases per week. Surveillance in Europe has also led to the identification of cases of BSE in Belgium, Denmark, France, Ireland, Liechtenstein, the Netherlands, Portugal and Switzerland and, most recently, in Germany, Spain and Italy. From 1995 through early December 2000, 88 human cases of vCJD were reported in the U.K, three in France and one in Ireland.

European countries have instituted a variety of public health control measures, such as BSE surveillance, the culling of sick animals, the banning of specified risk materials (SRMs), or a combination of these, to prevent potentially BSE-infected tissues from entering the human food chain. Due to its early outbreak, the most stringent of these measures have been applied in the U.K. In June 2000, the European Union Commission on Food Safety and Animal Welfare adopted a decision requiring all member states to remove SRMs from the animal feed and human food chains as of October 1, 2000; such bans had already been instituted in most member states.

U.S. ACTIONS: STEPS TO MINIMIZE ANY POSSIBLE RISK

No cases of BSE or vCJD have been identified in the United States despite ongoing nationwide surveillance. Working together, agencies within the federal government have taken a number of steps to minimize the risk of BSE in this country.

HHS Action Plan

In August 2001 HHS unveiled a department-wide action plan outlining new steps to improve scientific understanding of BSE, commonly known as "mad cow disease," and related diseases known as TSEs. The plan incorporates a comprehensive approach to further strengthen surveillance, increase research resources, and expand existing inspection efforts to prevent BSE and TSEs from entering or taking hold in the United States.

The Secreatary's action plan released today outlines four areas of responsibility-surveillance, protection, research and oversight-within HHS. This effort will be coordinated with other government agencies, the private sector, and the international community to contain this epidemic and assist those affected by it. The action plan is on the Web at: frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=2001_register&docid=01-21145-filed.

Dept. of Agriculture Import/Inspection Protections

The United States Department of Agriculture (USDA) has responsibilities for both public and animal health. USDA's Food Safety and Inspection Service operates a substantial program for inspecting animals intended for human consumption. USDA examines all cattle before they can be approved for use as human food; use of cattle with unidentified neurological diseases is prohibited. USDA examines more than 33 million cattle each year.

The USDA's Animal and Plant Health Inspection Service (APHIS) enforces explicit import regulations covering animals and animal products offered for import into the United States to prevent the importation of foreign exotic diseases such as BSE, foot-and-mouth disease, rinderpest and African swine fever. In 1989, USDA issued restrictions prohibiting the importation of live ruminants from countries where BSE is known to exist in native cattle. On December 12, 1997, APHIS took further steps to stop the importation of live ruminants and most ruminant products from all of Europe. As of October 31, 2000, USDA's aggressive BSE monitoring program has examined the brains of more than 11,700 U.S. cattle exhibiting various abnormal behaviors, including neurological symptoms. No evidence of BSE has been found in these U.S. cattle specimens.

HHS Protections

Agencies within HHS have a long-standing commitment to research, epidemiological studies and consumer protection involving BSE and variant and classic CJD.

Cattle Feed Restrictions: On June 5, 1997, the Food and Drug Administration (FDA) published a final regulation that prohibits the use of most mammalian protein in the manufacture of animal feeds given to ruminant animals, such as cows, sheep and goats. The regulation also requires process and control systems to ensure that feed for ruminants does not contain the prohibited mammalian tissue. This prohibition is a preventative measure designed to protect animals from potential transmissible degenerative neurological diseases such as BSE and to minimize any potential risk to humans. If a case of BSE were found in the United States, these measures would also help to prevent the spread of BSE through feeds in U.S. cattle. The rule took effect on August 4, 1997.

Protecting the Blood Supply: In August 1999, FDA issued guidelines to blood centers to reduce the theoretical risk of transmission of vCJD to recipients of blood products. This precautionary measure recommended procedures for deferring potential donors who may have been significantly exposed to food and other cattle-derived products in BSE-endemic countries. FDA's present guidelines ask blood centers to exclude potential donors who have spent six or more cumulative months in the U.K. between January 1, 1980, and December 31, 1996, from donating blood. Further revision to this guidance may be forthcoming with new information regarding other countries' BSE experiences. FDA's TSE Advisory Committee recently offered advice on revising the guidelines to include potential donors who have lived an aggregate of 10 years in France, Ireland and Portugal.

Protecting FDA-Regulated Products (including vaccines): Since 1992, FDA has sent a number of letters to manufacturers of FDA-regulated products providing guidance on the use of bovine materials from countries affected by BSE. In December 1993 and May 1996, FDA requested that manufacturers of FDA-regulated products intended for humans not use bovine-derived materials from BSE countries. There are some exceptions for products using gelatin produced from bones for oral consumption or cosmetic use if certain precautions are taken. In April 2000, FDA's Center for Biologics Evaluation and Research (CBER) issued a letter to manufacturers reminding them of the agency's strong recommendations not to use materials derived from ruminant animals from countries where BSE is known to exist or may exist.

CBER also asked licensed vaccine manufacturers to evaluate all bovine-sourced material used in vaccines at any stage of manufacturing. For materials of bovine origin, CBER has asked manufacturers to change the source of such material to BSE-free countries.

FDA inspects all manufacturers of FDA-regulated products on a routine basis to determine if manufacturers are following the agency's current recommendations. In addition, as applications for new products or changes to products are submitted, FDA ensures that the recommendations are being followed.

Research: The National Institutes of Health (NIH) has long been actively researching CJD and kuru, a related TSE disease in humans, as well as BSE in animals.

In the 1960s and 1970s, the Nobel Prize-winning team at the NIH Laboratory of Central Nervous System Studies conducted experiments on the oral transmission of CJD, kuru, and scrapie, a similar disease that affects sheep and goats.

In the 1980s, scientists at the University of California in San Francisco used extracts of scrapie-infected brains to postulate that the infectious agent was a single protein, PrP. Naming this class of infectious proteins as "prions," scientists showed that prions were a variant of normal proteins. Further research at NIH in the 1990s linked two outbreaks of CJD in Europe and Israel to a genetic mutation in the victims. It is now known that about 10 percent of CJD can be inherited, although it is not known if the genetic defect causes the disease or if another agent, such as a prion, is required.

Today, researchers in the United States and around the world are collaborating in the search for methods to detect, prevent and treat prion-linked diseases. NIH scientists are providing input to the investigation of vCJD cases in Europe and have developed a diagnostic test for the disease that can be performed before death.

Disease Surveillance: The Centers for Disease Control and Prevention (CDC) in Atlanta conducts surveillance for CJD through examination of death certificate data for U.S. residents. Based on this surveillance, during the period 1979 to 1998, the annual incidence of classic CJD (not the new variant CJD related to BSE) remained stable at approximately one case per million persons.

In addition to the ongoing review of national CJD mortality data, CDC conducted active CJD surveillance in its four established Emerging Infectious Program areas (in Minnesota, Oregon, Connecticut and the San Francisco Bay area) and in a metropolitan Atlanta site during April and May 1996.

In 1996, CDC worked with the Council of State and Territorial Epidemiologists to initiate an ongoing follow-up review of clinical and neuropathology records of CJD decedents aged younger than 55 years who are identified through the national mortality data analysis. This age group is targeted for surveillance because, while classic CJD is normally found in people aged 60 and older, vCJD is generally found in younger individuals.

Also in 1996, the American Association of Neuropathologists, in collaboration with CDC, alerted its members about the new vCJD and requested reports of any possible cases. These continuing surveillance efforts have not detected evidence of vCJD in the United States.

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Note: All HHS press releases, fact sheets and other press materials are available at http://www.hhs.gov/news.