Ovine catarrhal fever, also called bluetongue disease ("Bluetongue") is a viral disease. It is transmitted almost entirely through biting midges belonging to the Culicoides genus (C. imicola is the main vector). They infect animals by biting them. The disease does not affect human beings and is not therefore of any concern either to the general population or the consumer.
It is mostly found in sub-tropical regions because of the biology of its vector. It has emerged in recent years in Southern European countries (Greece, Italy, and Spain, and also Corsica) and in Northern Europe recently (Germany, Belgium, the Netherlands, and continental France).
The disease only affects ruminants and is mostly found in sheep. It has various symptoms: fever, lameness, oedema, mucosal cyanosis, and weight loss which may progress to death of the animal or a slow recovery, with significant financial losses. The current epizootic appears to be different since there are significant amounts of disease in cattle which are usually resistant to it.
The clinical signs which are seen in the current episode are oedema and buccal or nasal ulceration, lameness, oedema, and udder erythema.