Scientific Documents

Opinion of the Scientific Panel on biological hazards (BIOHAZ) on: “A quantitative assessment of risk posed to humans by tissues of small ruminants in case BSE is present in these animal populations”.

Summary (18 KB)

Opinion (4275 KB)

Summary

Following the confirmation of BSE in a goat in France on 28 January 2005, the European Commission (EC) (DG Sanco) invited the European Food Safety Authority (EFSA) and its Scientific Panel on Biological Hazards (BIOHAZ) to carry out “a quantitative assessment of risk posed to humans by tissues of small ruminants in case BSE is present in these animal populations”. The mandate requests a quantitative assessment of the risk posed by human consumption of meat derived from goats and sheep of different ages and genotypes in case BSE is confirmed.

It should take account of studies of the tissue distribution of the agent, prevalence evaluations and any other relevant data and, if possible, should consider different scenarios. In addition to current legislative measures the EC also stepped up its surveillance programme in sheep and goat. These new measures became mandatory in early 2005 and include a three step testing strategy in order to differentiate between scrapie and BSE for all confirmed positive scrapie cases in both sheep and goats and an increase in surveillance focusing on increased testing of goats for both healthy and fallen stock.

In carrying out this risk assessment, the BIOHAZ panel and its Working Group (WG) considered the available data on epidemiology and scientific reports on studies concerning the pathogenesis of BSE in sheep and goats as the basis for their assessment. Additional data gathered from the EC, individual Member States and EFSA and its Advisory Forum (AF) were also taken into account.

The BIOHAZ Panel WG concluded that there are currently not enough data on BSE in goats to allow a quantitative assessment of risk posed to humans by consumption of meat and meat products derived from goats infected with BSE.

The WG accepted that there were more experimental research data available for sheep both related to the pathogenesis of BSE in sheep and surveillance in the sheep population. Therefore, at this time, a risk assessment directed specifically at goat meat would necessarily be based on data from sheep. Such an approach would neither provide a proportionate response to the EC nor a science-based assessment of public health risks from goat meat and goat meat products. Although data are still lacking at present, the prospect of further information, including information related to exposure and other epidemiological factors, may allow a comprehensive and reliable quantitative risk assessment (QRA) for BSE in sheep in the future.

In considering all of the required data for a QRA of goat meat it was concluded that the most significant data to be obtained relate to the current prevalence of BSE in goats. It was acknowledged that steps had been taken to acquire this data but that complete results from recently initiated surveillance including discriminatory testing of goats for BSE will not become available before end 2005.

The WG concluded that a qualitative RA on goat meat could be made considering the existing risk management (RM) measures in place since 2001 and the results of the recently increased level of surveillance in goats and the discriminatory testing. For such a qualitative RA on goat meat, account is taken of a number of facts including that the goat found positive was born before the feed ban in 2001, and that currently, goats slaughtered for human consumption at a young age and born after the introduction of the feed ban, would present a lower risk than the adult population. Also other risk management measures in place (e.g. Specified Risk Material (SRM) list, rendering) contribute to the further reduction of the risk to the consumer. Moreover, the initial results of increased testing and discriminatory testing have not indicated any additional suspect BSE cases in goats or sheep. Therefore, the current risk in terms of BSE, related to the consumption of goat meat and goat meat products is considered at this time to be small for goats born after the feed ban, i.e. in 2001 and later.

The BIOHAZ panel recommended collecting additional data which would make a QRA possible in the future. In addition to the increased surveillance already initiated, it is also recommended to initiate as soon as possible additional research focusing on the experimental induction of BSE infection in goats. This would allow evaluation of the pathogenesis of the disease after oral exposure, including the tissue distribution and infectivity relative to age and incubation period, and thereby to determine the tissues most at risk as well as their infectivity load.

Further information:

Statement related to report of the EU TSE Community Reference Laboratory on TSE cases in sheep (45 KB)

Statement on the assessment of safety with respect to the consumption of goat meat and goat meat products in relation to BSE/TSE by the Scientific Panel on biological hazards (BIOHAZ) (40 KB)