Bovine ephemeral fever

Bovine ephemeral fever (BEF) is an arthropod vector born disease of cattle and is casued by the Ephemerovirus virus of the Rhabdoviridae family of virus. The Rhabdoviridae are a class V virus according to the Baltimore classification of viruses. The BEF virus is a bullet or cone shaped virion which consists of a negative, single stranded RNA genome with a lipid envelope and 5 structural proteins. The envelope glycoprotein G contains type specific and neutralizing antigenic sites. Theres has been recent evidence which demonstrated that the BEF virus induces apoptosis in several cell lines. It was howvever shown that apoptosis could be blocked by the caspase inhibitor (Z-VAD-fmk), indicating that bovine ephemeral fever virus induces caspase-dependent apoptosis in cultured cells.

Location
The virus has been found in tropical and subtropical regions of Asia, Africa and Australia.

Transmission
The virus is transmitted by an insect vector, this means that the virus is a zoonosis. In this case the insect vector linked to the virus is the mosquito. The particular species linked to the virus are the biting midges Culicoides oxystoma and C. nipponensis.

Disease Characteristics
The characteristics of the disease are the sudden onset of fever, stiffness, lameness, nasal and ocular discharges, depression, cessation of rumination and constipation. Although the pathogensis of the disease is complex it seems clear that the host inflammatory responses, mediated by the release of cytokines, are involved in the expression of the disease.