Bovine Spongiform Encephalopathy (BSE) in Canada

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Bovine Spongiform Encephalopathy (BSE)in Canada

• Pedro Piccardo, MD
• Division of Emerging and Transfusion-Transmitted
  Diseases
• Office of Blood Research and Review
• FDA-CBER

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BSE Background

• First described in UK in 1986 (gt180,000 cases in
  UK cattle to date)
• BSE present in most countries of Western Europe
• Peak of the epidemic in UK 1992-1993
• Surveillance in Canada began in 1992
• BSE detected in Alberta in 1993 (in one animal
  imported from UK)
• BSE recently found in Japan, Israel, Slovakia,
  Czech Rep, and Poland

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Basic assumptions

• BSE first arose in UK and was propagated through
  the recycling of infected bovine tissues into
  ruminant feed (meat-and-bone meal).
• The export of infected animals and infected feed
  from the UK spread the BSE agent to other
  countries were it was recycled and propagated via
  the animal food chain.

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1997 Ruminant Feed Bansin North America

• Canada implemented a rule that prohibits the
  feeding of most mammalian proteins to ruminant
  animals (feed ban).
• US implemented a similar rule the same year.

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Variant Creutzfeldt-Jakob Disease(vCJD)

• vCJD is a neurological disease in humans
  attributed to consumption of meat products from
  BSE-affected animals.
• Most vCJD cases have been in UK (135).
• vCJD was found in 5 other countries Canada (1)
  , France (6), Ireland(1), Italy (1), USA (1)
• Patients in Ireland, US , and Canada had spent
  extended time in UK.
• Some patients in France and the Italian patient
  had not visited UK.
• France imported significant amounts of beef from
  UK.

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BSE in Canada 2003

• Jan 31 An older breeder cow (6-8 yr) in Alberta
  was condemned with diagnosis of possible
  pneumonia and slaughtered (BSE not suspected).
• Head was collected and stored, carcass sent to
  inedible rendering for pet food, industrial
  use. Brain was not examined immediately due to
  backlog.
• May 16 BSE diagnosed in Alberta provincial lab by
  immunohistochemistry (PrPSc in medulla).
• May 18 BSE confirmed in Winnipeg.
• May 20 BSE confirmed in UK as typical BSE.
  Canada announced case USDA import prohibition.

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Rendering

• Canadian authorities assured that the carcass had
  not entered human food chaininedible rendering
  only.
• Rendered product went to
• 8 feed mills. All farms receiving feed (not
  intended for ruminants) contacted to determine if
  any ruminants on premises. If so, they were
  further investigated.
• 2 farms. Depopulated, could not rule out
  inadvertent feeding of poultry feed to cattle on
  same premises.
• Pet food manufacturer (Alberta). Dog food was
  shipped to one firm in US. There is no evidence
  that dogs contract any TSE. US firm asked
  customers to return food to distributors for
  proper disposal.

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Canadian Response Plan(lines of inquiry)

• Feed Over 200 farms have been investigated,
  found in compliance with required feeding
  practices.
• Case herd No information available about use of
  MBM on last farm where BSE cow lived the farm
  was depopulated and animals tested.
• Trace back Search for the possible birthplace of
  BSE affected cow (probably Saskatchewan, possibly
  Alberta) was completed. Herds where BSE cow
  co-mingled (potentially exposed to same feed)
  were investigated.
• Trace forward Herds where offspring from case
  herd might have lived were investigated.

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US Follow-up

• US federal agencies (FDA CVM Center for
  Veterinary Medicine, FDA ORA Office of
  Regulatory Affairs, USDA APHIS Animal Plant
  Health Inspection Services, USDA FSIS Food
  Safety Inspection Service) are following up 5
  bulls imported into the US from one possible herd
  of origin of BSE cow.

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Results

• Approximately 2700 cattle brains have been
  analyzed by rapid test (PrPSc ELISA) and
  immunohistochemistry.
• All animals tested negative (except for the
  single positive index cow).
• Approximately 25 farms have been investigated
• (Alberta, Saskatchewan, British Columbia).
• June 9 Canadian Food Inspection Agency (CFIA)
  announced that active investigation of the case
  is ending. Additional testing and information
  gathering will continue. An international review
  team (OIE) in Canada is evaluating the situation.
• A recent risk assessment (Dec 2002) had indicated
  that the likelihood of BSE affecting cattle in
  Canada was very low.
• Current prevalence of BSE in Canada must be very
  lowrisk probably lower than before 1997.

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BSE Canada Further Information

• BSE in Canada will be a topic of discussion at
  the next meeting on July 17-18, 2003 of the
• FDA Transmissible Spongiform Encephalopathies
  Advisory Committee
• The Canadian Food Inspection Agency (CFIA)
  maintains a web site at
• http//www.inspection.gc.ca

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Agenda TSEAC July 17-18

• Safety of bovine gelatin in oral and topical
  drugs, food and cosmetics
• BSE in Canada and potential implications for
  FDA-regulated products
• Decontamination of medical equipment and
  facilities (FDA-regulated devices, human tissue
  establishments)