News and Highlights

On April 24, 2012, the U.S. Department of Agriculture (USDA) confirmed a BSE case in a dairy cow in California.

For more information:

• USDA/APHIS notive: Update from APHIS Regarding a Detection of Bovine Spongiform Encephalopathy (BSE) in the United States
• USDA/APHIS Final Report Summary Report: California Bovine Spongiform Encephalopathy Case Investigation [PDF – 179 KB]
• Final Feed Investigation Summary—California BSE Case, July 2012.

See the USDA's About BSE for more information about BSE in the United States.

On February 18, 2011, the Canadian Food Inspection Agency (CFIA) confirmed a BSE case in a dairy cow born in Alberta in 2004. It reported that no part of the affected animal carcass entered the human food or animal feed systems. CFIA identified the animal’s birth farm and initiated an investigation. The age and location of the infected animal are consistent with previous cases detected in Canada. The case was detected through the national BSE surveillance program, which continues to play an important role in Canada’s strategy to manage BSE. This case underscores the importance of maintaining the multiple "firewalls" in Canada and the United States designed to prevent animal and human exposures to the BSE agent, including particularly slaughter house and rendering plant controls that reduce the risk of specified risk materials (tissues of infected cattle most likely to transmit BSE) from entering into animal feed or human food.

See the Canadian Food Inspection Ageancy (CFAI): ARCHIVED—Bovine spongiform encephalopathy (BSE) cases confirmed in Canada in 2011.

For more information about BSE in Canada, see the Canada Food Inspection Agency (CFIA)Bovine Spongiform Encephalopathy (BSE)

On February 28, 2010, the Canadian Food, Inspection Agency (CFIA) announced the confirmation of another bovine spongiform encephalopathy (BSE) in a 70.5 month-old beef cow from Alberta.

For more information about BSE in Canada, see the Canada Food Inspection Agency (CFIA) website.

On May 15, 2009, the Canadian Food, Inspection Agency (CFIA) announced the confirmation of bovine spongiform encephalopathy (BSE) in an 80-month-old dairy cow from Alberta.

For more information about BSE in Canada, see the Canada Food Inspection Agency (CFIA) website.

On April 27, 2009, a regulation issued by FDA will go into effect establishing an enhanced BSE-related feed ban in the United States. The date of required compliance to this regulation, however, was recently moved back six months to October 26, 2009. The ban will further harmonize BSE feed control measures in the United States with those in Canada. In addition, FDA continues to enforce its important 1997 mammalian-to-ruminant feed ban through its BSE inspection and BSE feed testing programs.

On August 15, 2008 the Canadian Food Inspection Agency (CFIA) announced the confirmation of the third of three cases of bovine spongiform encephalopathy (BSE) from two western provinces of Canada (Alberta, 2 cases; British Columbia, 1 case) that died in 2008. Two were in dairy cows and one in a beef cow. These animals were each born in one of the consecutive years, 2001-2003.

For more information about BSE in Canada, see the Canada Food Inspection Agency (CFIA) website.

In August 2008, several ARS investigators reported that a rare, genetic abnormality that may persist within the cattle population "is considered to have caused" BSE in the atypical BSE animal from Alabama in 2006.

For more information:

Identification of a Heritable Polymorphism in Bovine PRNP Associated with Genetic Transmissible Spongiform Encephalopathy: Evidence of Heritable BSE.

BSE Case Associated with Prion Protein Gene Mutation.

On April 25, 2008, FDA issued a new regulation that will take effect in 12 months in order to allow livestock, meat, rendering, and feed industries time to adapt their practices to comply with the new regulation. This regulation will bar high-risk materials from all animal feed, including pet food. It will help prevent against the accidental feeding of cattle with ingredents that may be contaminated with the BSE agent. Such contamination of ruminant feed may occur during the manufacturing or transportation process.

For more information:

FDA Strengthens Safeguards for Consumers of Beef

BSE Case Associated with Prion Protein Gene Mutation.

On May 2, 2007, the 11th case of BSE in a Canadian-born bovine was identified by the Canadian Food Inspection Agency (CFIA). The eleven cases include one in a Canadian-born bovine identified in the United States in 2003 (see bar graph below). Preliminary information indicates that this most recent BSE case occurred in a mature dairy cow from British Columbia born in 2001, about 4 years after the 1997 Canadian feed ban.

For more information about BSE in Canada, see the Canada Food Inspection Agency (CFIA) website.

On February 7, 2007 the Canadian Food Inspection Agency (CFIA) reported a confirmed case of bovine spongiform encephalopathy (BSE) in a mature bull from Alberta. On March 6, the CFIA confirmed that this animal was born in 2000 which was after the 1997 feed ban.

This is the 10th reported case of BSE in a cow born in Canada and the 6th such case reported since the beginning of 2006. The CFIA report indicated that Canada's enhanced feed ban is scheduled to come into effect on July 12, 2007, and that BSE should be eliminated from the Canadian cattle herd within approximately 10 years.

For more information about BSE in Canada, see the Canada Food Inspection Agency (CFIA) website.

On August 23, 2006 bovine spongiform encephalopathy (BSE) was confirmed by the Canadian Food Inspection Agency (CFIA) in a mature beef cow from Alberta. The cow's estimated age was between eight and ten years of age. Based on this range, exposure to the BSE agent likely occurred either before the feed ban's introduction or during its early implementation. This is the ninth case of BSE identified in Canada.

• July 2006, the CFIA confirmed two cases of bovine spongiform encephalopathy (BSE). On July 4, 2006 the CFIA confirmed BSE in a beef cow from Manitoba. This animal was at least 15 years of age and was born before the Canadian 1997 feed ban. 
• A second case of BSE was confirmed by CFIA on July 13, 2006. This case occurred in a 50-month old dairy cow from Alberta. Based on its age, this cow was exposed to BSE after the 1997 feed ban was put into place.

No part of these cows entered the human or animal feed system. When a case of BSE is identified, CFIA conducts a comprehensive investigation including identification of the birth farm, herd mates, feed used, and any potential routes of BSE exposure.

For more information about BSE in Canada, see the Canada Food Inspection Agency (CFIA) website.

In July 2006, the Canadian Food Inspection Agency (CFIA) confirmed two additional cases of bovine spongiform encephalopathy (BSE).

• On July 4, 2006 the CFIA confirmed BSE in a beef cow from Manitoba. This animal was at least 15 years of age and was born before the Canadian 1997 feed ban.
• A second case of BSE was confirmed by CFIA on July 13, 2006. This case occurred in a 50-month old dairy cow from Alberta. Based on its age, this cow was exposed to BSE after the 1997 feed ban was put into place.

No part of either of these cows entered the human or animal feed system. CFIA is conducting a comprehensive investigation of both of these cases of BSE. The investigation includes identification of the birth farms, identifying herd mates and the feed used, locating any offspring of the infected cows, and in the case of the 50 month old dairy cow, identifying other cattle born on the premises within 12 months before or after the birth of the infected cow. U.S. Department of Agriculture (USDA) staff has been invited by CIFA to participate in these investigations.

For more information about BSE in Canada, see the Canada Food Inspection Agency (CFIA) website.

On March 13, 2006, the U.S. Department of Agriculture (USDA) announced the confirmation of bovine spongiform encephalopathy (BSE) in a cow in Alabama. This is the eighth confirmed case of BSE in North American cattle and the second case since the beginning of 2006. Three cases were detected in the United States and five in Canada. One of the two previous U.S. cases was of Canadian origin, and the first of the five cases detected in Canada was in a cow that had been imported from the United Kingdom.

The newly confirmed case was identified in a non-ambulatory (downer) cow on a farm in Alabama. The animal was euthanized by a local veterinarian and buried on the farm. USDA surveillance is targeted at those animal populations in which BSE would most likely be found. These animals primarily include clinically abnormal or deceased cattle, which would not be expected to enter the human food supply. The cow in Alabama did not enter either the animal or the human food chains, according to the USDA announcement. USDA is working with Alabama animal health officials to conduct an epidemiologic investigation to gather additional information about the age and herd of origin of this animal, which had resided on the Alabama farm for less than a year.

The agency also will work to identify other cows born in the same herd within one year of the affected animal, and any offspring. In addition, USDA is working with Food and Drug Administration (FDA) officials to determine any feed history that may be relevant to the investigation. "Experience worldwide has shown us that it is highly unusual to find BSE in more than one animal in a herd or in an affected animal's offspring. Nevertheless, all animals of interest will be tested for BSE," according to the USDA statement.

BSE is a progressive neurological disorder of cattle that results from infection by an unconventional transmissible agent. Strong evidence indicates that BSE has been transmitted to humans, primarily in the United Kingdom, causing a variant form of Creutzfeldt-Jakob disease (vCJD). As of March 2006, a total of 190 cases of vCJD have been reported worldwide; of these, 160 occurred in the United Kingdom. Two cases have been reported in the United States; for both of these cases, there was clear epidemiologic evidence that the disease was acquired in the United Kingdom.

For additional information about the newly confirmed BSE case, see USDA announcement: Statement by USDA Chief Veterinary Officer John Clifford (DVM) Regarding Positive BSE Test Results March 13, 2006.

On June 24, 2005, the U.S. Department of Agriculture announced receipt of final results from The Veterinary Laboratories Agency in Weybridge, England, confirming BSE in a cow that had conflicting test results in 2004. No parts of the animal entered the human and animal food supply. As a result of this BSE positive animal, the USDA plans to develop a new laboratory testing protocol to evaluate future inconclusive BSE screening test results.

For additional information, please see:

• June 24, 2005 USDA Announces BSE Test Results and New BSE Confirmatory Testing Protocol
  USDA press release
• BSE, from the USDA Animal and Plant Health inspection Service (APHIS)
• Fact sheet: APHIS IHC Test Variables [PDF – 40 KB]

On January 2 and 11, 2005, the Canadian Food Inspection Agency (CFIA) announced the confirmation of bovine spongiform encephalopathy (BSE, also known as "mad cow" disease) in two cows from the province of Alberta. One of the cows was born in October 1996 and the second cow was born in March 1998, after the Canadian government instituted a ruminant feed ban in 1997. No part of these animals has entered the human food supply, according to CFIA.

These two BSE-positive cows bring the total number of BSE-infected cows identified in or linked to Canada to four, including a BSE-positive cow identified in Washington State that was later determined to have originated from Alberta. CDC is in communication with the U.S. Department of Agriculture and will continue to monitor these developments closely.

For more Information:

More information on BSE in North America is available from the Canadian Food Inspection Agency on BSE.

United States Department of Agriculture, About BSE.

On December 23, 2003, the U.S. Department of Agriculture (USDA) announced a presumptive diagnosis of bovine spongiform encephalopathy (BSE, or "mad cow" disease) in an adult Holstein cow from Washington State. Samples were taken from the cow on December 9 as part of USDA's BSE surveillance program. The BSE diagnosis was made on December 22 and 23 by histopathology and immunohistochemical testing at the National Veterinary Services Laboratory, Ames, Iowa. The diagnosis was confirmed by an international reference laboratory in Weybridge, England, on December 25. Preliminary trace-back based on an ear-tag identification number suggests that the BSE-infected cow was imported into the United States from Canada in August 2001.

USDA, in close cooperation with Canadian agricultural authorities, has launched an epidemiologic investigation to determine the source of the disease. Beef from the slaughtered cow had been processed for human consumption. On December 23, 2003, the Food Safety and Inspection Service (FSIS), USDA announced the recall of all beef from cattle slaughtered on December 9 at the involved slaughter plant.

Strong evidence indicates that BSE has been transmitted to humans primarily in the United Kingdom, causing a variant form of Creutzfeldt-Jakob disease (vCJD). In the United Kingdom, where over 1 million cattle may have been infected with BSE, a substantial species barrier appears to protect humans from widespread illness. As of December 1, 2003, a total of 153 vCJD cases had been reported worldwide; of these, 143 cases had occurred in the United Kingdom. The risk to human health from BSE in the United States is extremely low.

CDC monitors the trends and current incidence of CJD in the United States by analyzing death certificate information from U.S. multiple cause-of-death data compiled by the National Center for Health Statistics. With the support of the Council of State and Territorial Epidemiologists, CDC conducts follow-up review of clinical and neuropathology records of CJD decedents younger than 55 years of age. In addition, during 1996-1997, in collaboration with the American Association of Neuropathologists (AANP), CDC established the National Prion Disease Pathology Surveillance Center at Case Western Reserve University in Cleveland, Ohio. This pathology center provides free, state-of-the-art diagnostic services to U.S. physicians. It also helps to monitor the possible occurrence of emerging forms of prion diseases, such as vCJD, in the United States. For more information about the center visit its website at: http://www.cjdsurveillance.com.

For additional information about the case of BSE in Washington State and general information on prion diseases, see the following websites:

• USDA About BSE
• FDA BSE
• NIH, NINDS Creutzfeldt-Jakob Disease Information Page