Appendix 23
CONCEPT NOTE
1. Proposal prepared by: ...........................{Member of the Standing Technical Committee} 2. Short description of the background to issue or situation
Role of sheep in maintaining or spreading FMD in a temperate European climate with mixed sheep and cattle farms (UK, 2001) The issue of whether to include sheep in a emergency vaccination programme in a normally free country has arisen at EUFMD Sessions (including Closed Session of the Research Group, 2007) on multiple occasions. It is also a frequent question from countries in middle-east, where cattle are routinely vaccinated and the role of sheep is considered important but where an evidence base is missing to support decision for or against sheep vaccination. The best information base, and probably the climatic and husbandry situation that represents the optimum for sheep playing a role in transmission of FMD, comes from the UK epidemic in 2001. If restricted to the period after the movement ban, the information should assist to answer the question of the role of sheep as the “entry portal - the first infected animal” on a holding. If sheep are not shown to be important as a first receiver of infection on a holding, then the value of protecting sheep by vaccination would appear limited. 3. Key bottlenecks/issues addressed Overall issue to be addressed: • optimising the use of limited human and vaccine resources in emergencies; • omitting sheep would save time, resources and may benefit the post-vaccination exit strategy; • therefore is there merit in recommending the vaccination of sheep (in addition to cattle) during an epidemic of FMD? 4. Proposed action How to answer this? Analyse data from FMD outbreak in UK 2001 post introduction of movement ban plus incubation period, to attempt to determine: 1) What proportion of IPs had infected sheep and were these mixed or single species farms; 2) Were sheep infected first (age of oldest lesions) on mixed species farms? 3) How long were sheep infected before discovered and how does this compare with cattle? 4) Were sheep the source of infection for IPs after the movement ban? Data available (from UK sources, following UK epidemic in 2001): Species present Species with lesions Age of lesions in affected species First lesion date Virus isolation results Serology database
Available in final reports database Available in final reports database Available in final reports database Available in final reports database using age of lesions and report date Available for all IPs from which samples were submitted. Not always certain which species was sampled Available for all sampled farms. Almost always sheep that were sampled.
76th Session of the Executive Committee of the European Commission for the Control
of Foot-and-Mouth Disease
121
