1. (Bovine spongiform encephalopathy)
BSE
(Bovine spongiform encephalopathy)

2. Structure What is BSE? Cause Infections in Humans
Geographic Distribution & Prevention
Diagnostic Test
Summary
References

3. 1. What is BSE?
BSE (Bovine spongiform encephalopathy)= mad cow disease
was first reported in the United Kingdom in the 1980s
symptoms: incoordination, nervous, violent, has trouble walking or getting up
once the symptoms develop always progressive and fatal
incubation period: 2-8 years

4. 1. What is BSE?
member of the transmissible spongiforme encephalopathies (TSEs)
prion diseases
progressive encephalopathies
affect brain and nervous system
spongy degeneration in brain and spinal cord
amyloid plaques
Brain from a healthy cow,
as seen under a microscope using special stains.
Brain from a cow sick with BSE,
as seen under a microscope using special stains.  

5. 2. Cause first reported in the United Kingdom in the 1980s
caused by recycling of ruminant proteins
1979 changed parameter in meat and bone meal production
20 min, 133°C, 3 bar min, 80°C, 3 bar
diseased sheeps were used to produce meat and bone meal (“Scrapie“)
“Scrapie“
symptoms: itching, excessive lip smacking, convulsing collapse
Transmissible spongiform encephalopathy (TSE)

6. 2. Cause Prion Hypothesis
responsible for the transmissible spongiforme encephalopathies (TSEs)
prion in the Scrapie form (PrPSc) is an infectious agent composed of protein in a misfolded form
“PrP + PrPSc  2 PrPSc“ (refolding of native proteins in diseased state)
consequences: exponentially increase, tissue damage, cell death, amyloid plaques
PrP PrPSc
3 x α-helix x α-helix
2 x β sheet x β sheet

7. 3. Infections in humans infection: eating contaminated food
variant Creutzfeld-Jakob disease (vCJD)
incubation period: 11 to 12 years
median age of onset: 26 years
symptoms: psychiatric symptoms, incoordiantion, memory loss, persistent painful sensory symptoms, slurred speech
no treatment available, only supportive care
Spontaneous (genetic) Creutzfeld-Jakob Disease in humans (CJD)
variant Creutzfeld-Jakob Disease (vCJD)
Kuru Disease
BSE

8. 3. Infections in humans
Spontaneous (genetic) Creutzfeld-Jakob Disease in humans (CJD)
variant Creutzfeld-Jakob Disease (vCJD)
Kuru Disease
BSE
Creutzfeld-Jakob Disease (CJD)
Sporadic CJD:
develops spontaneously
accounts for 85 percent of cases
first appears between ages 60 and 65
Familial CJD:
heredity form caused by changes in the prion protein gene
genetic changes are "dominant”
accounts for about 10 to 15 percent of cases

9. 3. Infections in Humans
Spontaneous (genetic) Creutzfeld-Jakob Disease in humans (CJD)
variant Creutzfeld-Jakob Disease (vCJD)
Kuru Disease
BSE
Kuru Disease
among members of the Fore tribe of Papua New Guinea
caused by cannibalism
Affected especially women and children of the tribe

10. 4. Geographic distribution & Prevention
first reported in the United Kingdom in the 1980s
2006: 99 cases
2008: 35 cases
: 7 – 11 cases each year
Cases of BSE: European countries, Canada, in the U.S., Israel, Japan
Countries free of BSE: Iceland, Australia, New Zealand

11. 4. Geographic Distribution & Pervention
Prevention:
2001: feed ban and active surveillance for BSE in the E.U.
2001: over the age of 30 months
2008: over 48 months
2011: over 72 months
2013: no obligation anymore
Germany: over 96 months
: animals tested  0 animals infected

12. 5. Diagnostic Tests For BSE in Cattle no live animal test for BSE
diagnosed by detecting prions in the CNS:
polyacrylamide gel electrophoresis (proteins seperated)
Proteolysis by adding protease K
Western blotting (detect prion)

13. 6. Summary BSE is a relatively new disease
fatal neurodegenerative disease
caused by a prion
result of recycling ruminant proteins
humans can be infected (vCJD)
prevention: surveillance programs and not feeding meat and bone meal

14. 7. References
Dumpitak, C.; Riesner, D. Der Beweis der Prionenhypothese. Biologie in unserer Zeit. 2005, 35, 374‐383