Transmissible Spongiform Encephalopathies (TSE) D. Heim

What are TSE? Family of diseases Neurological disease accumulation of abnormal prion protein spongiform degeneration of the brain progressive and lethal long incubation period transmissible

Which diseases are belonging to TSE? Variant Creutzfeldt-Jakob-Disease Feline Spongiform Encephalopathy Bovine Spongiform Encephalopathy Chronic Wasting Disease Transmissible Mink Encephalopathy Gerstmann-Straeussler- Scheinker-Syndrom Creutzfeldt-Jakob-Disease Kuru Scrapie 1700 1750 1800 1850 1900 1950 2000 year

Only a few veterinarians in a few regions knew animal TSEs (scrapie) Disease awareness veterinarians low Only a few physicians knew human TSEs Disease awareness physicians low

Bovine spongiform Encephalopathy (BSE) in the United Kingdom ( MAD COW DISEASE )

Origin of BSE in UK

Origin of BSE in UK Insufficient sterilisation of meat and bone meal

Origin of BSE in UK Insufficient sterilisation of meat and bone meal Use of meat and bone meal in cattle feed

Origin of BSE in UK Insufficient sterilisation of meat and bone meal Use of meat and bone meal in cattle feed BAN OF FEEDING MBM TO RUMINANTS

First BSE cases in Ireland Portugal Switzerland France

Export meat and bone meal from UK

BSE and Variant Creutzfeldt-Jakob- Disease (vcjd) - the link

Reaction of the public Media hype Public crisis Massive decrease beef consumption

Sporadic Human TSE Classical sporadic Creutzfeldt-Jakob-Disease Known since 1920 incidence of sporadic cases worldwide similar (0.3-2 cases per 1 Million inhabitants per year) Mainly older patients Hereditary Familiar CJD Gerstmann-Sträussler-Scheinker-syndrome Fatal familiar insomnia Acquired Kuru Iatrogenic CJD Variant CJD (vcjd)

Variant CJD Different from sporadic CJD Younger age Different clinical signs Different pathology Most probable source of infection: consumption of meat products containing CNS

Which tissues are infectious in BSE- cattle? Main infectivity in Brain Spinal cord Dorsal root ganglia Distal ileum

Crucial measure to minimize risk for consumer Ban of specified risk material (brain,...) in human food United Kingdom 1989 Switzerland 1990 European Union 2000 (some EU-countries with BSE before)

Reaction of the countries Countries with BSE: Most implementation of more rigorous measures Contries without BSE Ban of imports from countries with BSE we are BSE-free Countries with surveillance found BSE disadvantages Countries without surveillance did not find BSE advantages

How to find out whether there is a risk of having BSE? World Organisation for Animal Health BSE risk status can only be determined after assessing BSE risks

GBR I: Highly unlikely Risk assessment EU Argentina, Australia, Iceland, New Caledonia, New Zealand, Panama, Paraguay, Singapore, Uruguay, Vanuatu GBR II: Unlikely but not excluded GBR III: Likely but not confirmed or confirmed at a lower level GBR IV: Confirmed at a higher level Botswana, Brazil, Colombia, Costa Rica, El Salvador, India, Kenya, Mauritius, Namibia, Nicaragua, Nigeria, Norway, Pakistan, Sweden, Swaziland Albania, Andorra, Austria, Belarus, Belgium, Bulgaria, Chile, Croatia, Denmark, Canada, Cyprus, Czech Republic, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Ireland, Israel, Italy, Latvia, Lithuania, Luxembourg, Malta, Mexico, Poland, The Netherlands, Romania, San Marino, Slovak Republic, Slovenia, South Africa, Spain, Switzerland, Turkey, USA United Kingdom, Portugal

Improvement of surveillance Passive surveillance (notification by owner/veterinarian) Disease awareness Willingness to notify cases Laboratory competence Active surveillance: testing of risk populations Switzerland 1999 80 70 60 no. of cases 50 40 30 6 3 6 8 20 4 5 3 8 5 0 10 0 2 9 1 5 1 4 9 1 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 France 2000 Year of diagnosis France 200 150 100 50 0 1990 1992 1994 1996 1998 2000 EU 2001

First cases detected in 2000/2001 Denmark Spain Germany Italy Czech Rep Greece Slovak Rep Slovenia Austria Finland

vcjd in the UK 30 25 20 15 18 15 28 10 10 10 5 0 1990 1991 1992 3 1993 1994 1995 1996 1997 1998 1999 2000 PREDICTIONS Less than 870,000 (Ghani et al, 2000) Few hundred-millions (d'aignaux et al 2001) 2001 2002 2003 2004 2005 2006

Reaction of the public Media hype Public crisis Massive decrease beef consumption

2001: Japan 1.BSE case outside Europe

2003: Canada

2005: USA

Source: FAO

1990 1992 1994 1996 1998 2000 2002 2004 2006 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 1986 1988 1990 1996 2000 2002 2004 BSE-situation 1200 1000 800 600 400 200 0 Year of diagnosis Number of BSE-cases 40000 35000 30000 25000 20000 15000 10000 5000 0 Number of BSE-cases (UK) United Kingdom (UK) TOTAL EU 15 without UK Japan 12 10 8 6 4 2 0 Year of diagnosis 1990 1992 1994 1996 1998 2000 2002 2004 2006 No of cases Canaday 6 4 2 0 Year of diagnosis No of cases

30 25 vcjd-situation UK 28 158 cases 20 15 10 5 0 3 10 10 18 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 15 20 17 2000 2001 2002 2003 18 9 5 5 2004 2005 2006 3 (+1) vcjd-cases blood transfusion associated 2 (+1) with clinical signs 1 case without clinical signs Human to human transmission very effective 0

vcjd-situation in other countries France 21 Ireland 4 Spain 1 Portugal 1 Netherlands 2 Italy 1 Japan 1 Canada 1 USA 3

Conclusion BSE and vcjd-cases decreasing measures taken effective Efficient surveillance needed Control of implemented measures needed Many countries without reported BSE - risk is unknown Risk assessment needed Risk communication important

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