Bluetongue (BT) is a non-contagious, viral disease affecting domestic and wild ruminants (primarily sheep and including cattle, goats, buffalo, antelope, deer or elk) that is transmitted by midges of the Culicoides species.
The virus which causes BT is identified as a member of Orbivirus genus of the family Reoviridae. The BT virus species, or serogroup, contains 24 notifiable serotypes, and some other atypical serotypes recently described.Infection with bluetongue virus (BTV) can occur asymptomathically in many animals, but can cause fatal disease in a proportion of infected ruminants. The severity of disease varies among different animal species and viral strains with symptoms being most severe in sheep resulting in deaths, weight loss and disruption in wool growth. In highly susceptible sheep, morbidity can be as high as 100%. Mortality averages from 2-30% but can be as high as 70%. It is not known to affect humans.
