Brussels, 5 Decembre 2001
BSE - Scientific Steering Committee publishes opinions about the origin of BSE and other BSE related issues
The Scientific Steering Committee (SSC), advising the European Commission about BSE and other multidisciplinary issues today publishes new opinions on the origin and transmission of BSE, on the BSE cases found in the UK amongst cattle born after the ban on feeding meat-and-bone meal , and on the surveying requirements for obtaining reliable data on the prevalence of BSE and TSE in cattle, sheep and goats. The Committee also updated a standing opinion on the sourcing of ruminant materials for medical devices.
The opinion on the origin and transmission routes for BSE mainly confirms the standing scientific consensus hypotheses of a prion of unknown origin as the agent for transmitting the disease via feed and cross-contamination of feed mainly, and via maternal transmission to a lesser extent. The SSC considers that not one of the alternative hypotheses about a 'third' transmission route has so far been substantiated by scientific evidence. Evidence is equally very limited if not absent for hypotheses about factors influencing the susceptibility of cattle to BSE.
The six BSE cases found so far in the UK amongst cattle born after the August 1996 ban on feeding meat-and-bone meal to cattle give the SSC currently no reason to assume there is a higher BSE risk in the UK than previously assumed. Therefore there is no need to revise scientific advice on the UK Data Based Export Scheme (DBES) of any other BSE related opinions.
The Committee further adopted an opinion on the surveying and testing requirements for obtaining statistically authoritative and reliable data on the prevalence of BSE and TSE in cattle, sheep and goat populations in the EU. The opinion sets out the technical criteria for sample design, sample size, confidence intervals, etc. Sampling of the cattle population should be targeted on the group of so-called risk animals (e.g., fallen stock etc. ) This also means the sample size can be kept significantly lower than in the case of sampling healthy animals sent for slaughter. In the goat and sheep population risk animals are much more difficult to identify. Therefore, the survey for most countries will need to be targeted at healthy animals sent for slaughter, and need to cover a larger number of animals. Surveys would have to be accompanied by measures ensuring that animals suspected of being infected with TSE are not deliberately kept outside the testing programme.
The SSC further updated its opinion on the safe sourcing of medicinal products from countries were BSE is highly unlikely to be present. The use of catgut sourced from such countries does not present a risk according to the scientists.