Deer Brain Tissue

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Deer Brain Tissue Normal
CWD
Spongiform Vacuoles
Neurons
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BSE Prevention
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Forms of Transmissible Spongiform
Encephalopathies (TSEs)

• Sporadic

• Inherited

• Acquired

• Iatrogenic

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Characteristics of all TSEs

• Central Nervous System Failure

• Long Incubation Period

• No Cure

• Death

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HumanTransmissible Spongiform Encephalopathies

• Creutzfeldt-Jakob Disease (CJD)

• Fatal Familial Insomnia (FFI)

• Gerstmann-Straussler Syndrome (GSS)

• Kuru

• Variant Creutzfeldt-Jakob Disease (vCJD)

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AnimalTransmissible Spongiform Encephalopathies

• Scrapie

• Transmissible Mink Encephalopathy (TME)

• Chronic Wasting Disease (CWD)

• Bovine Spongiform Encephalopathy (BSE)

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AnimalTransmissible Spongiform Encephalopathies

• Scrapie in Sheep and Goats

• Transmissible Mink Encephalopathy (TME)in Mink

• Chronic Wasting Disease (CWD)in Deer and Elk

• Bovine Spongiform Encephalopathy (BSE)
• in Cattle, Cats, Kudu, and Nyala

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Cause?

• Agent not fully characterized

• Smaller than smallest known virus

• No detectable immune or inflammatory response

• Disinfectants

• 600oC (1112oF)

• 3 year burial

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Agent Theories

• VIRUS

• VIRION

• PRION

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Agent Theories

• VIRUS

• VIRION

• PRION

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vCJD from BSE?

• vCJD -Human
• BSE Cattle
• Prion Protein is Indistinguishable

• Feline Spongiform Encephalopathy (FSE)
• TSE in Kudu and Nyala

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Confirmed Cases BSE in UK
C O W S
Data from Office International Des Epizooties
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Confirmed Cases of Variant Creutzfeldt Jakob
Disease in UK
P E O P L E
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UK CowsBSE
UK PeoplevCJD
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BSE Diagnostics

• No live animal test

• Need brain tissue

• Negatives do not guarantee absence of
  infectivity

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Distribution of Infectivity

• Never Found in
• Milk
• Skeletal muscle of food animals

spinal cord dorsal root ganglia
brain trigeminal ganglia eye
bone marrow
distal ileum
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Distribution of Infectivity

• BSE in Sheep

pituitary
brain
spinal cord
vagus nerve
Blood
lymph nodes
spleen
intestine
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Prevention in U.S.

• Import Regulations

• Feed Rule

• Surveillance

• Formal Risk Assessment

• Response Plan

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• Import Regulations

• Import Restrictions - countries with BSE
• July 1989 - live ruminants
• November 1989 - ruminant products

• Import Restrictions - Europe
• December 1997
• All live ruminants and most ruminant products

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• Import Regulations

• Import Restrictions - Europe
• December 2000 all rendered animal protein
  regardless of species

• Restrictions extended to Japan September 2001

• Evaluations of other countries

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U.S. Feed Rule

• Prohibits Feeding Ruminants Mammalian Protein
  except

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U.S. Feed Rule

• Prohibits Feeding Ruminants Mammalian Protein
  except

• Milk Products

• Blood Products

• Gelatin

• Plate Waste

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Confirmed Cases BSE in UK
C O W S
Feed Ban
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BSE Samples May 1990 through September 30, 2002
C O W S
Total 36,594
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Year
Data from USDA APHIS NVSL
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Formal Risk Assessment

• Harvard / Tuskegee Universities

• Began in 1998

• Released November 30, 2001

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Harvard / TuskegeeRisk Assessment

• Describe potential pathways of BSE infectivity
  into national herd or food supply.

• Characterize and quantify steps in pathways.

• Identify key steps for research or risk
  management.

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Harvard/Tuskegee StudyConclusion

• Our analysis finds that the U.S. is highly
  resistant to any introduction of BSE or a similar
  disease.

• BSE is extremely unlikely to become established
  in the U.S.

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BSE Response Plan

• First version early 1990's

• Updated often to reflect new scientific
  knowledge and personell changes.

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Plan Expectations

• Herd Quarantined

• Presumptive Positive Sample Hand Carried to UK
  for Confirmation.

• Herd Purchased and Destroyed by Government

• Trace Animals and Feed

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Producer Preventive Actions

• Look for and obey cautionary statement Do Not
  Feed Cattle or Other Ruminants on feed labels.

• Be aware that Pet Food often contains prohibited
  materials.

• Avoid cross contamination of ruminant feed with
  feeds that contain prohibited material.

• Keep feed records.

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Record Keeping Requirement for Ruminant Producers

• Any feeds fed containing any animal protein,
  regardless of species fed, excluding pet food fed
  to pets.

• Invoices date, quantity, supplier

• Feed Labels

• Minimum of 1 year

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BSE NEVER Found in U.S.
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http//www.wa.gov/agr
Neil Lanning nlannning_at_agr.wa.gov 360-902-2052
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Scrapie ID Program
http//www.aphis.usda.gov/vs/scrapie.htm http//a
nimalagriculture.org/scrapie/scrapie.htm
Linda.V.Carpenter_at_aphis.usda.gov Olympia Office
USDA APHIS VS 360-753-9430
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Brain Stem
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Brain Stem
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Deer Brain Tissue Normal
Sectioning Artifact
Neurons
Blood Vessel
Nuclei of Glial Cells
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Deer Brain Tissue Chronic Wasting Disease
Nuclei of Glial Cells
Neurons
Neuron
Spongiform Vacuoles
Blood Vessel
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Salt
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Bone Meal
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Mill Run
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Mill Run
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Mill Run and Bone Meal