EN
Bluetongue (BT) is an infectious, non-contagious disease of animals, especially domestic animals and wild ruminants. BT is considered endemic in wildlife in large parts of Africa and North America. Most species of wild ruminants are susceptible to BTV infection, though frequently asymptomatically. The pathogenicity of BT among wildlife ranges from asymptomatic to fatal. Wild sheep, such as as bighorn and mouflon, are susceptible to BTV infection and can develop fatal clinical disease just like domestic sheep. Clinical disease also results from experimental or natural infection of antelope, wapiti, musk, ox, bison, yak, white-tailed deer and African buffalo, whereas blesbock, mountain gazelle, roe deer, red deer and Eurasian elk do not show clinical signs after natural or experimental infection, which can only be recognized by the presence of BTV-specific antibodies or viral RNA. Some camelids are also reportedly susceptible to BTV infection. A severe clinical form of this lethal disease has been reported in naturally infected llamas, whereas an experimental infection of llamas induced antibodies against BTV, but no clinical signs were observed. No clinical signs of BT have been observed in experimentally infected dromedary camels, but all animals seroconverted, and RNA BTV was isolated from the blood during viraemia, which suggests that camels may act as a reservoir for BTV and play an important role in its transmission. Wild animals, particularly cervids (because of their wide distribution in Europe), could be used as sentinels for the surveillance of BTV.