A presumptive diagnosis of Bluetongue based on clinical and pathological signs can frequently be made. For a definitive diagnosis laboratory confirmation may be required.
The following techniques are available for the definitive diagnosis of Bluetongue infection.
The sensitivity of tests may vary between laboratories but in general, viral genome can be detected in blood samples from 3 days after infection onwards (by real time PCR) and positive antibody detection by ELISA can be expected from 5 to 7 days after infection.
Salivation due to lesions in the mouth in a sheep with Bluetongue
Large areas of necrosis with sloughing of the mucosa on the tongue