Bluetongue Disease: A Non-Contagious Viral Infection Threatening Ruminants Worldwide

Understanding the Scope of Bluetongue Disease

Bluetongue disease (BT) is a highly prevalent viral infection affecting domestic and wild ruminants across the globe. This non-contagious disease is primarily transmitted through insect vectors and can impact a wide range of species, including sheep, cattle, goats, buffalo, antelope, deer, and dromedaries.

Clinical Manifestations in Sheep

In sheep, BT manifests with distinct clinical signs that arise from vascular endothelial damage. Affected animals may exhibit edema, swelling, and congestion in various body parts, such as the head, neck, and tongue. The tongue, in particular, can become swollen and discolored, giving rise to the name "bluetongue." Additional symptoms may include lameness, reduced appetite, respiratory distress, and even abortion.

Etiology and Transmission

Caused by the bluetongue virus (BTV), BT is a recognized arthropod-borne viral disease. The virus is transmitted primarily by biting midges, particularly belonging to the genus Culicoides. These insects serve as vectors, carrying the virus between susceptible ruminants and facilitating the spread of infection.