What Canadians Need to Know About Mad Cow Disease
This backgrounder was prepared in 2001
What Is Mad Cow Disease?Mad Cow disease, or its scientific name Bovine Spongiform Encephalopathy (BSE), is a fatal brain-wasting disease in cattle which was first identified in the United Kingdom (UK) in 1986. The disease has an incubation period lasting 4-7 years, but ultimately is fatal for cattle within weeks of its onset.(1)
BSE is one of a number of Transmissible Spongiform Encephalopathies (TSEs) - a family of diseases in humans and animals which are characterized by sponge-like lesions in the brain. Other examples of TSEs are found in sheep, deer, elk, mink and even the feline species. In deer and elk, TSE is commonly referred to as "Chronic Wasting Disease" and in sheep the disease is known as "scrapie." It is widely believed that cattle in Britain developed BSE as a result of being fed the rendered carcasses of dead sheep that were infected with scrapie.
There is a great deal of speculation as to the original cause of Mad Cow disease. According to the widely-held "prion theory", the BSE agent is composed largely, if not entirely, of a self-replicating protein referred to as a "prion." Another theory suggests that the agent is virus-like and possesses nucleic acids which carry information. Strong evidence collected over the past decade supports the prion theory, but the ability of the BSE agent to form multiple strains is more easily explained by a virus-like agent.
Epidemiological studies conducted in the UK suggest it is spread through cattle feed prepared from carcasses of other ruminants - any of a group of even-toed, hoofed, cud-chewing mammals, including cattle, deer, and elk. No one knows for sure how the first cow (or cows) got BSE, but we know it spread throughout Britain and eventually the world through the cannibalistic practice of making cattle feed out of the bits of cattle (offal) that are not fed to humans. Like a "chain-letter", offal from a Mad Cow infected many more cattle and offal of those cattle infected many more.
According to British customs figures, more than 200,000 tons of potentially contaminated feed were exported around the world.(2) The UK Sunday Times reported that Prosper de Mulder, Britain's largest rendering company, exported potentially contaminated material to Canada.(3,4) In a worldwide alert the UN Food and Agriculture Organisation reported that meat and bone meal from Europe was imported by more than 100 countries since 1986, including Canada.(5) All those countries are at risk, said the report, and added "All countries which have imported cattle or meat and bone meal that originated from Western Europe, during and since the 1980s, can therefore be considered at risk from the disease."(6) As of December 2000 approximately 180,000 cases of Mad Cow disease were confirmed in the UK.(7) Cases of BSE have been confirmed in cattle in Belgium, Denmark, France, Ireland, Luxembourg, Netherlands, Portugal, Switzerland, Germany, Spain, Liechtenstein, Italy, Greece, Czech Republic, Poland, Slovakia, Slovenia, Finland, Austria, Israel and Japan.(8)
What Is New Variant Creutzfeldt-Jakob Disease?New variant Creutzfeldt-Jakob disease (vCJD) -- or "Human Mad Cow disease" -- is also a fatal brain-wasting disease. Characterized by dementia and loss of motor control, this hideous disease was first identified in the United Kingdom in 1996. It is widely accepted in the scientific community that the most likely cause of vCJD is from exposure to the BSE agent via "dietary contamination by affected bovine central nervous system tissue", or in more simple terms, from eating infected meat.(9) Originally it was believed that Mad Cow disease could not jump from cattle to humans. The hypothesis of a link between vCJD and Mad Cow disease was first raised because of the association of these two in time and place. Experts quickly observed that the agent responsible for vCJD is consistent with the agent that causes Mad Cow disease in cattle; In other worlds - it was the same disease.(10) Scientific studies have since confirmed that vCJD and BSE are indeed the same disease.(11)
vCJD is classified as a Transmissible Spongiform Encephalopathy (TSE) because of characteristic spongy degeneration of the brain. The first person known to develop symptoms of what turned out to be vCJD became ill in 1994. Early in the illness, patients usually experience psychiatric symptoms, which most commonly take the form of depression or, less often, a schizophrenia-like psychosis. Early in the illness, unusual sensory symptoms, including "stickiness" of the skin, are experienced in approximately half of all cases. Neurological degeneration, including unsteadiness, difficulty walking and involuntary movements, occurs as the illness progresses. By the time of death patients are completely immobile and mute. vCJD is often confused with CJD, or "Creutzfeldt-Jakob disease", another brain-wasting human TSE disease which causes sponge-like degeneration of the brain. However, CJD, which afflicts approximately one in a million people worldwide, is caused by a hereditary predisposition.
According to Mad Cow disease expert Dr. Steven Dealer, like cattle, thousands - perhaps millions - of people may have been infected before the disease was first identified in 1996.(12) As of June 1st, 2001, there were 104 confirmed cases of vCJD. What worries Dr. Dealer is the alarming increase in new cases being diagnosed. There were 15 people diagnosed with vCJD in 1999 and 42 more diagnosed in 2000.(13) Because no one knows the length of the incubation period, which is currently speculated to be as long as 40 years, it is uncertain how many people will ultimately be infected. Dr. Dealer estimates that as many as 5 million people may have been exposed to the fatal disease in the United Kingdom alone.(14)
Is Canada Safe From Mad Cow Disease?Alberta actually imported a live cow with Mad Cow disease back in 1993. The Canadian government raced to destroy the "Mad" cow - along with more than 400 other cattle from the same herd - but some cattle slipped through the cracks. A report by the European Union's Scientific Committee noted that "eleven imported cattle that were found to be carrying a risk of being infected [with BSE] entered the Canadian food or feed chain".(15) Furthermore, it was reported in the Globe and Mail that CFIA officials were sent "scrambling" to track down 20 cattle imported from Japan, which had recently been diagnosed with its first case of Mad Cow disease. Once again, Ottawa failed to track down all the animals. It was later realized that four of the suspect cattle had already been slaughtered and may have entered the Canadian food supply.(16)
In other words, cattle potentially carrying Mad Cow disease have already been processed into feed and fed to Canadian cattle. However, according to Dr. Claude Lavigne, an official from Canada's Food Inspection Agency (CFIA), Mad Cow disease is "a European Disease and that's about it."(17) Officials from the Geneva-based World Health Organisation (WHO) disagree. The WHO has concluded that Mad Cow disease is a "global disease" and "no country is immune."(18) In fact, Germany, France, Belgium and Italy had all pronounced they were "free" of Mad Cow disease. Mad Cow disease has now been documented in all those countries.(19)
According to Michael Hansen, a Mad Cow expert with the Consumers Union in New York, dozens of countries around the world who imported potentially contaminated animal feed from Europe - including Canada and the US - may already have the fatal disease in their herds and simply aren't aware yet.(20) According to Hansen, governments insist they have erected a "firewall" against Mad Cow disease, but in reality it's "more like a white picket fence."(21) In 2001, Hansen told the Canadian media: "I would predict that if they tested enough animals (in Canada) they would find a positive."(22)
In 2000, Canada only tested 900 cattle for Mad Cow disease.(23) That is less than 0.01 % of Canada's beef cattle herd which numbers 11,000,000.(24) To put this in perspective, European countries were testing thousands of cattle per week in an attempt to detect and eradicate the horrific disease! Maybe Canadian regulators and industry aren't looking because they are afraid of what they might find. According to government sources, the only cattle being checked for Mad Cow disease are those that display neuro-degenerative behavior. This is a problematic scenario because not all cattle carrying the BSE agent exhibit the trademark brain-wasting symptoms.(25)
The CFIA contends it is taking every precaution to keep Mad Cow disease out of Canada. The US Food and Drug Administration admitted that only 2700 of 9500 rendering plants inspected were complying with regulations designed to keep Mad Cow disease out.(26) Last year alone Canada imported 15.5 million kilograms of meat byproducts from the US. Canada also imported 125,000 kilograms of British meat and bone meal in the 1990s after it had been identified as a likely cause of Mad Cow disease.(27,28) Furthermore, Statistics Canada documentation shows that between 1990-2000 Canada imported millions of kilograms of potentially contaminated blood meal, meat scraps and waste meat from the United Kingdom and European countries.
Shockingly, over 2.8 million kilograms of this potentially contaminated material was imported after 1996 - after it was established that humans could contract vCJD from eating infected meat.(29) This contradicts claims by Agriculture Minister Lyle Vanclief, who categorically denied that Canada ever imported bone meal from countries known to have Mad Cow disease. "Never," said Vanclief outside the Commons, "Canada has not imported meat and bone meal from the European Union."(30,31) Is Minister Vanclief lying or is he being misled by his advisors?
Despite the reality that Mad Cow disease is spreading around the world, federal regulators have not taken preventative measures to protect Canada. The willful blindness that characterized Health Canada's approach to the handling of the hazard of blood contamination in the past is clearly being repeated today.(32) Health Canada officials have responded to the Mad Cow threat by saying they have set up a committee to "review" the situation - and added: "We're not worried."(33) The United Nation's Food and Agriculture Organisation states that "all countries which have imported cattle or meat and bone meal from Western Europe, especially the UK, during and since the 1980s, can be considered at risk from the disease."(34) Canada has imported millions of kilograms of such products.(35)
When Mad Cow disease started to sweep across Britain, government officials went to extremes to hide it from the public. For six months, there was an embargo on publishing information about Mad Cow disease. When information started to leak out, the British government told the public - "trust us" - and went to great lengths to convey the false impression that Mad Cow disease was not transmissible to humans and thus posed no threat.(36)
Eventually, the concealment of information stopped and the truth came out. Mad Cow disease was killing people. How many lives would be lost as a consequence of the British government's refusal to take precautionary measures? Has the Canadian government not learned anything from the British experience? Unfortunately, no. Canadian officials are now repeating the same mistakes made by the British Government.
What Should Canada Be Doing?Government must immediately implement an exhaustive testing regime for identifying Mad Cow disease. By only testing 900 cattle a year we are putting Canadians at risk. Like several European countries we should be testing thousands of cattle a week.
Canada should immediately ban meat and bone meal from entering the food chain. Cows are not cannibals - they are herbivores and should not eat other animals. While it is often reported that Canada has banned cattle-to-cattle feeding practices, this simply isn't true. Under Canadian law it is presently legal for cattle to be fed a diet derived from mammal "blood, gelatin, rendered animal fat or their products."(37) In other words, cattle materials (like blood and fat) are still making their way into cattle feed. It is also legal for pigs and chickens, fed on rendered cattle materials, to be rendered and fed back to cattle. This practice must be stopped immediately. In a British experiment, a pig injected with brain material from a BSE cow contracted a TSE.(38)
Furthermore, feed mix-ups do happen and sometimes cattle eat other animals feed. According to William Leiss, President of the prestigious Royal Society of Canada, the federal government should implement a full ban on such feeding practices. "Stop recycling animal protein," said Mr. Leiss. "All of it. Period. That's the answer, because of what we know." (39) The Canadian government should heed recommendations from the World Health Organisation and immediately legislate a total ban on rendered animal protein in livestock feed. If there are more cases of Mad Cow disease in Canada, this precautionary measure will prevent it from spreading further.
Shockingly, the carcass of Canada's recent case of Mad Cow disease was sent to a rendering facility were it entered the animal feed chain. This is in direct violation of a 1996 WHO recommendation that states: "No part or product of any animal which has shown signs of a TSE should enter any food chain (human or animal)." This dangerous behaviour must stop immediately.
The WHO and the UN Food & Agriculture Organisation are also urging countries to ban feeding cattle with ruminant based feeds. This includes feeds derived from deer and elk which may be infected with Chronic Wasting Disease (CWD), a close cousin of BSE. In Canada no such measures have been adopted. It is still common practice for "road-kill" deer and elk to be sent to the rendering plant to be processed into animal feed - despite the fact that government regulators have documented thousands of Canadian elk and deer with CWD. While scientists don't know if CWD can be transmitted from elk and deer to people and/or cattle, it is best to err on the side of caution until ongoing scientific studies have been concluded. Canada should also be deferring blood donations from high-risk groups like deer hunters and elk game farmers who may have contracted CWD.
The federal government should also ban vaccines, medicines and other health products made from bovine materials. Approximately 400 such products are available in Canada. At the very least, these potentially hazardous products should be clearly labelled so they can be traced back to their origin in the case of a related outbreak. There are nine common vaccines known to be made with bovine materials, some of which are administered for polio, diphtheria and tetanus. It was reported in the New York Times that despite repeated requests from the US Food and Drug Administration, some of the world's largest drug companies are still using bovine materials from countries known to have Mad Cow disease in their herds.(40) A senior official from Health Canada insists they are "studying" the situation - even though he acknowledges that the threat from such bovine-based products "can't be ruled out."(41)
Officials from Health Canada and the CFIA met behind "closed-doors" with cattle industry representatives to discuss the Mad Cow epidemic.(42) Refusing to allow public health advocates attendance in the meeting illustrates the collusion between government regulators and the regulated. To quote Justice Horace Krever, Health Canada "must not delegate their functions to others, nor rely on consensus decision making as a substitute for independent judgement."(43)
Warning: System FailureThe federal government has been quietly dismantling the Food and Drugs Act and undermining the regulatory responsibilities of the Canadian government in a shift to a "Risk Management" regime - where illness and death are considered acceptable risks. In his last report, Auditor General Denis Desautels concluded that the CFIA was so understaffed that it could not guarantee the safety of Canadian meat.(44)
Parliament must revoke regulatory responsibilities for food safety from the CFIA and give them to an in-house, independent agency which reports to the Minister of Health. This agency must be provided with ample resources to undertake rigorous inspection based on a precautionary principle framework - not a "manage the damage" Risk Management scheme.
The CFIA is in a clear conflict of interest as both a "promoter" and "regulator" of the agriculture industry.(45) Government regulators must be completely independent from industry - this is paramount. To paraphrase Justice Krever, government must regulate in the public interest, not in the interest of the regulated.(46) There must be an independent public inquiry into the scandalous behavior of the CFIA and Health Canada. The inquiry should report directly to parliament - not the Prime Minister's office - and any officials linked to wrong-doing should be prosecuted. People who knowingly violate the Food & Drugs Act and the Department of Health Act are violating Canada's criminal code and should be held responsible. Accountability saves lives.
Precautionary Principal means that, in the face of scientific uncertainty, one should proceed with caution. Government should not wait for scientific certainty about the spread of a disease before it acts to reduce risks.(47) Federal regulators must apply the precautionary principle. Risk management is the language of corporations - not public protection.(48) If the dire threat of Mad Cow disease doesn't justify taking precautionary measures - what does?
When evidence of the dangers of Mad Cow disease first began to appear in Britain, policy makers didn't heed the precautionary principle. Instead of basing their policies on a worst-case scenario, they placated industry and hoped for the best. To quote the memorable words of British epidemiologist Sheila Gore, the British government was playing "Russian Roulette with no information on the odds."(49) Let's not let history repeat itself. Let's apply the precautionary principle now.
Bradford Duplisea is an independent Ottawa-based researcher
who often works on health care and food safety issues for the
Canadian Health Coalition.
He can be reached at:
Footnotes:1. Risk Assessment of Transmissible Spongiform Encephalopathies in Canada, Prepared by Joan Orr and Mary Ellen Starodub for the Health Canada Science Team on TSEs, June 30, 2000; and World Health Organisation, BSE Fact sheet, http://www.who.int/inf-fs/fact113.html
2. United Press International, Feb. 4, 2001, "BSE-contaminated feed said to reach 70 countries"
3. The Canadian Press, Sunday, February 11, 2001, "Canada imported potentially contaminated animal feed, British figures indicate"
4. U.K. government figures indicate that Canada received 30,000 kilograms of meat and bone meal in 1993; 22,000 in 1994; 31,000 in 1995; and 42,000 in 1996, Canadian Press, Sunday, February 11, 2001
5. UN Food & Agriculture Organisation Press Release, http://www.fao.org
6. The Canadian Press, Sunday, February 11, 2001
7. World Health Organisation, BSE Fact sheet, http://www.who.int/inf-fs/fact113.html
8. World Organisation for Animal Health, Number of reported cases of bovine spongiform encephalopathy (BSE) worldwide, http://www.oie.int/eng/info/en_esbmonde.htm
9. The BSE Inquiry, UK, 1999, http://www.bse.org.uk/
10. World Health Organisation, vCJD Consultations, 1996
11. Scientists first identified pathological features similar to vCJD in the brains of macaque monkeys inoculated with BSE and later established that the transmission characteristics of BSE and vCJD in mice are due to the same causative agent.
12. CBC Radio, BSE expert - Dr. Stephen Dealer on vCJD, January 2001
13. CBC Radio, BSE expert - Dr. Stephen Dealer on vCJD, January 2001
14. Special Report on BSE by Mark Kennedy, Ottawa Citizen, June 2, 2001 "It kills every last victim"
15. Canadian Broadcast Corporation's The National, "Could mad cow be in Canada already", Feb. 21, 2001, http://tv.cbc.ca/national/trans/T010221.html
16. The Globe and Mail, "Mad-Cow threat prompted search for cattle", June 10, 2002
17. The Toronto Star, Jan. 20, 2001 "Europe's mad cow scare raises Canadian alarms"
18. The Toronto Star, Jan. 20, 2001 "Europe's mad cow scare raises Canadian alarms"
19. World Health Organisation, http://www.who.int
20. The Canadian Press, Feb. 15, 2001, "Mad cow infection could be in Canadian beef but not detected: scientists"
21. The New York Times, Jan. 28, 2001 "Americans wake up to threat of Mad Cow Disease"
22. The Canadian Press, Feb. 15, 2001, "Canada's mad cow testing falls short: Scientists"
23. The Canadian Press, Feb. 15, 2001, "Canada's mad cow testing falls short: Scientists"
24. Government Statistics, Canadian Food Inspection Agency
25. David Westaway (scientist from the University of Toronto) on CBC's The National: "Mad Cow Disease" - Three Part Series By Kelly Crowe (Part II), February 2001
26. Reuters, Jan. 12, 2001 "Some Feed Makers Don't Follow 'Mad Cow' rules"
27. Britain's U.K. Customs and Excise Agency
28. Canadian Press, Sunday, Feb. 11, 2001, "Canada imported potentially contaminated animal feed, British figures indicate"
29. Statistics Canada International Trade Division, http://www.healthcoalition.ca/factsheets/import-data.pdf
30. "Canada Imported Potentially Contaminated Animal Feed, British Figures Indicate," Canadian Press, Feb. 9, 2001
31. Canadian Press, Sunday, February 11, 2001
32. Letter to Allan Rock from the Canadian Health Coalition, Jan. 29, 2001, "Re: Dereliction of Duty to Protect Canadians from BSE and vCJD", http://www.healthcoalition.ca/rockletter1302001.html
33. The National Post, Jan. 27 2001, pg. A15
34. UN FAO Press Release, http://www.fao.org/waicent/ois/PRESS_NE/PRESSENG/2001/pren0103.html
35. Statistics Canada International Trade Division, http://www.healthcoalition.ca/factsheets/import-data.pdf
36. The BSE Inquiry, UK, 1999, http://www.bse.org.uk
37. Canadian Food Inspection Agency, Regulations: Food for Ruminants, Livestock and Poultry (Part XIV), "Prohibited Materials"
38. BSE/vCJD expert Michael Hansen, Ph.D., Consumers Union, Consumer Policy Institute, "Point of View", http://www.consumersunion.org/food/genewsmny798.htm
39. The Ottawa Citizen, June 6, 2001 "The Dangers of Recycling Animal Protein: With the heightened fear surrounding mad cow disease, the spotlight is now on rendering, an `invisible industry' that makes products from animal remains."
40. The New York Times, Feb. 8, 2001, "Five drug makers use material with mad cow link"
41. The Ottawa Citizen, Jan. 24, 2001 "Beware of bovine byproducts: experts"
42. The Ottawa Citizen, Feb. 17, 2001, "Mad cow meeting too cosy: critics" & Calgary Herald, Feb. 17, 2001, "Mad cow disease on federal agenda"
43. Commission of Inquiry on the Blood System in Canada by the Honourable Justice Horace Krever: Final Report (Volume 3, Page 996)
44. Report of the Auditor General, The Office of the Auditor General of Canada, February 2001, http://http://www.oag-bvg.gc.ca/
45. The Royal Society of Canada, Elements of Caution: Recommendations for the Regulation of Food Biotechnology in Canada, http://www.rsc.ca
46. Commission of Inquiry on the Blood System in Canada by the Honourable Justice Horace Krever: Final Report (Volume 3, Page 995)
47. Commission of Inquiry on the Blood System in Canada by the Honourable Justice Horace Krever: Final Report (Volume 3, Page 994)
48. Dr. Michelle Brill-Edwards, Senior Drug Reviewer, Health Canada (1988-1992), Speaking at a Food Safety conference in Ottawa, 1998
49. Sheila Gore, 1996 "Bovine Creutzfeldt-Jakob Disease: Failures of Epidemiology Must be Remedied"