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BSE: The European on-going story |
J. R. BLANCHFIELD, Consultant, 17 Arabia Close, Chingford, London, E4 7DU, United Kingdom An outline is given of the background to BSE in Europe, and of measures aimed at protecting animal health and human health. While there is strong evidence that the cause of the UK epidemic was the feeding of infected meat-and-bone meal (MBM) to cattle, its origin is less certain and may be due to a combination of factors. In December 2000, the EU Council of Ministers decided on new controls across the EU Member States, essentially similar to the UK controls, but with post-mortem testing of cattle over 30 months from January 2001. In addition to clinical cases in some European countries, testing by EU Member States has revealed cases in apparently healthy cattle, most likely resulting from feeding to cattle of UK mammalian MBM imported as pig and poultry feed prior to 1996. Cases may emerge in other countries which imported this material. WHO has stated that over 100 countries are at risk. BSE infectivity and (new) variant CJD (vCJD) infectivity carry the same biochemical "fingerprint". Although the scientific evidence does not prove a causal connection, the evidence is consistent with the transmissibility of BSE infectivity to at least some humans (possibly to all humans but at varying incubation rates); and taken in conjunction with related circumstances it increases the likelihood of a causal connection. At 2 November 2001, there was a cumulative total of 111 definite and probable cases of vCJD. There are 3 confirmed cases in France. Although attempts have been made to estimate minimum and maximum figures (widely apart) it is still not possible to draw from the figures to date any long-term conclusions, whether optimistic or pessimistic, as to likely future incidence.
Session 18, The prion diseases: Human health and food safety
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