Catarrhal Fever of Sheep

a noncontagious, viral, transmissible disease of sheep characterized by infection of the mucous membranes of the mouth, swelling of the tongue, and fever. The disease was first detected in Africa in 1876; it is also found in the USA, the Near East, and on the Iberian Peninsula. It has not been reported in the USSR. In view of the danger that it presents, catarrhal fever of sheep is included by the International Bureau of Epizootics in the convention for mandatory notification.

Under natural conditions, sheep, especially lambs, are susceptible, as are cattle, goats, and antelopes to a lesser extent. The source of the infection is sick and convalescent sheep, whose blood may retain the virus up to four months. Blood-sucking insects from the genus Culicoides are carriers of the causative agent of the disease. In Africa, wild animals (antelopes) are a natural reservoir of the causative agent. Catarrhal fever of sheep is a seasonal disease that occurs chiefly in low-lying areas in warm and very rainy weather. No specific treatment has as yet been devised. Animals that recover from the disease acquire permanent immunity. Prevention and control calls for quarantine and vaccination of sheep in a threatened zone.