The first outbreaks of sheep bluetongue in Khartoum province, Sudan

Outbreaks of bluetongue (BT) have occurred for the first time among sheep in Khartoum province, the Sudan. The morbidity rate approach­ ed 100% while the mortality rate was 40%. The disease was successfully repro­ duced by experimentally infecting lambs, and the virus was reisolated from them. Viral antigen was detected directly in the blood plasma and serum from the naturally and experimentally infected lambs by using the complement fixa­ tion (CF) and the agar gel immunodiffusion (AGID) tests. The virus was fur­ ther isolated in chick embryos (CE), baby hamster kidney cells (BHK-21) and chick-embryo fibroblasts (CEF), and it was eventually identified as BT. It is recommended that blood plasma and serum from BT-suspected or sick sheep be used for the rapid serological diagnosis of the virus.