This study has examined the efficacy following intramuscular administration of a 
recombinant Semliki Forest virus (rSFV) vaccine, encoding the prME and NS1 
proteins of louping ill virus (LIV), in sheep. Administration of rSFV-LIV 
vaccine resulted in transient detection at the injection site and draining lymph 
node only and no dissemination to distal sites. In addition, the recombinant 
vaccine offered complete protection against subcutaneous challenge with LIV, and 
partial protection following intranasal administration of LIV. Protected animals 
had no pathological changes normally associated with LIV infection, and had 
developed high antibody titres. In contrast, the two animals not protected 
exhibited classical clinical signs and neuropathological lesions of LIV 
infection. These findings indicate that rSFV-based vaccines have the potential 
to be developed as effective prototype vaccines for LIV.