What causes Bluetongue?
Bluetongue is caused by reoviruses. A specific type of gnat transmits the viruses. The gnats take blood from an infected animal and spread the disease to other cattle when they take additional blood meals. Following an infection in cattle, the virus incubates for 3 to 10 days, and may remains active in the blood for 60 to 80 days. During this active phase, red blood cells of the infected animal are destroyed, and the disease can be transmitted to other animals. Red blood cells in the blood of sheep and wild ruminants have a shorter lifespan than in cattle, thus decreasing the time that the blood is infected.
