BTVPUR AlSap 8 Uses For active immunisation of sheep to reduce viraemia and clinical signs caused by Bluetongue Virus Serotype 8. For active immunisation of cattle to reduce viraemia caused by Bluetongue Virus Serotype 8. The onset of immunity has been demonstrated 3 weeks after the primary vaccination course. The duration of immunity has not yet been established. The efficacy of the vaccine has not been fully established.