8. The European BSE crisis
*Note that the BSE epidemic of 1990-2001 was mainly concentrated in the western European Union countries
Bovine Spongiform Encephalopathy (BSE), is a fatal cow disease. The disease is sometimes called ‘mad cow disease’
because it causes cows to act strangely and collapse on the spot (see
picture). It is concentrated mainly in the cow's brain, spinal cord and
certain organs such as the spleen.
BSE was caused by feeding cows with meat and bone meal, a high-protein substance obtained from butchered sheep and cows. This was applied in Europe because soybeans, the main ingredient of regular cow feed, was hard to obtain.
The
accumulation of prions (proteinaceous infectious particles) over many
generations caused animals to fall ill, increasing the infectious tissue
concentration in newly produced meat. In Europe it was first discovered
in British cattle in 1986. Contrarily to other European countries, in
Britain it was not required for the animal feed to undergo a steam
boiling process for sterilization. This gave the infectious agents a
chance to spread. In 1996 the British mistake came to light and European
countries banned the import of British cow meat, causing the British
meat industry to suffer major losses.
The ban of British meat export appeared to have been implemented too late and consequently BSE started spreading throughout Europe (table 1). Many countries started to test its animals. When BSE was suspected on a farm transporting of animals and meat was banned. The animals were killed and their carcases burned. This may have caused air pollution, because cow incineration was carried out in open air without proper filtering on many occasions.
BSE was caused by feeding cows with meat and bone meal, a high-protein substance obtained from butchered sheep and cows. This was applied in Europe because soybeans, the main ingredient of regular cow feed, was hard to obtain.
The
accumulation of prions (proteinaceous infectious particles) over many
generations caused animals to fall ill, increasing the infectious tissue
concentration in newly produced meat. In Europe it was first discovered
in British cattle in 1986. Contrarily to other European countries, in
Britain it was not required for the animal feed to undergo a steam
boiling process for sterilization. This gave the infectious agents a
chance to spread. In 1996 the British mistake came to light and European
countries banned the import of British cow meat, causing the British
meat industry to suffer major losses.The ban of British meat export appeared to have been implemented too late and consequently BSE started spreading throughout Europe (table 1). Many countries started to test its animals. When BSE was suspected on a farm transporting of animals and meat was banned. The animals were killed and their carcases burned. This may have caused air pollution, because cow incineration was carried out in open air without proper filtering on many occasions.
Table 1: year of discovery of first BSE cases by country
| Country | Year |
| Ireland | 1989 |
| Portugal | 1990 |
| Switzerland | 1990 |
| Belgium | 1993 |
| Netherlands | 1997 |
| Denmark | 2000 |
| France | 2000 |
| Spain | 2000 |
| Italy | 2001 |
| Germany | 2003 |
Many
countries banned the use of meat and bone meal after the outbreak of
BSE in Europe. However, in Germany meat and bone meal was still
permitted in cow feed until 2000. This caused an aftermath of the
epidemic in 2003.
BSE was not only harmful to cows; in 1996 it was discovered that a human equivalent of the fatal brain disease existed. The infection is known as Creutsfeldt Jacobs Disease (vCJD). Once infectious prions are activated, the disease runs its course within 12 to 18 months and ultimately results in death. Symptoms include depression, coordination problems, memory loss and mood swings, pain in the limbs, bad headaches, cold extremities, pain in the feet, rashes and short-term memory loss.
It
is assumed that humans are affected with the BSE-related disease by
consuming the organs and tissues from cattle in which the BSE-causing
agents are present. Infection can only occur when consumption cows with
BSE are 30 months old or older. Estimates state that 400.000 cattle
infected with BSE entered the human food chain in the 1980s. The age of
these cows prior to slaughter is unknown.
vCJD killed nearly 90 people in the UK by 2003. Deaths from the disease were also reported in France and Italy. In 2004 a total of 158 Europeans acquired or died from vCJD, most of which were Britains (148). It is now suspected that slaughtering practises and horticultural fertilization practices may also cause the human variant of BSE, but this is still researched.
Table 2: reported BSE cases in Europe by country
BSE was not only harmful to cows; in 1996 it was discovered that a human equivalent of the fatal brain disease existed. The infection is known as Creutsfeldt Jacobs Disease (vCJD). Once infectious prions are activated, the disease runs its course within 12 to 18 months and ultimately results in death. Symptoms include depression, coordination problems, memory loss and mood swings, pain in the limbs, bad headaches, cold extremities, pain in the feet, rashes and short-term memory loss.
It
is assumed that humans are affected with the BSE-related disease by
consuming the organs and tissues from cattle in which the BSE-causing
agents are present. Infection can only occur when consumption cows with
BSE are 30 months old or older. Estimates state that 400.000 cattle
infected with BSE entered the human food chain in the 1980s. The age of
these cows prior to slaughter is unknown.vCJD killed nearly 90 people in the UK by 2003. Deaths from the disease were also reported in France and Italy. In 2004 a total of 158 Europeans acquired or died from vCJD, most of which were Britains (148). It is now suspected that slaughtering practises and horticultural fertilization practices may also cause the human variant of BSE, but this is still researched.
Table 2: reported BSE cases in Europe by country
| Country | Number of BSE cases (cows) |
| Austria* | 2 |
| Belgium | 125 |
| Chez Republic* | 9 |
| Denmark | 13 |
| Finland* | 1 |
| France | 891 |
| Germany | 312 |
| Greece* | 1 |
| Ireland | 1353 |
| Italy | 117 |
| Lichtenstein* | 2 |
| Luxembourg | 2 |
| Netherlands | 75 |
| Poland* | 14 |
| Portugal | 875 |
| Spain | 412 |
| Switzerland* | 453 |
| UK | 183.803 |
The
incidences of BSE are relatively small in number, but the discovery of
the disease had a dramatic effect on European beef consumption, which
fell to 27%. In 2001 the European BSE epidemic ceased, having only an
aftermath in Germany in 2003 (see above). Even after bringing the BSE
epidemic under control people are still being diagnosed with its human
variant each year, because of its long incubation period. The full
extent of the outbreak may still be unknown.
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