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The Equine encephalosis virus (EEV) is a virus of the Orbivirus genus, and a member of the Reoviridae family, related to the African Horse Sickness Virus (AHSV) and the Blue Tongue Virus (BTV).〔 〕 First described in South Africa over a hundred years ago by Arnold Theiler, EEV is the causative agent of Equine Encephalosis (EE), an arthropod-borne disease transmitted by the ''Culicoides spp.'' midges affecting all equids.〔 〕 Since then the disease has become both widespread and prevalent, taking on epidemic proportions in certain parts of the country. Serological studies estimated a presence of anti-EEV antibodies in over 75% of all South African horses.〔 〕 Prior to 2008, the Equine Encephalosis Virus had been identified and isolated only in South Africa, where seven antigenetically distinct serotypes, EEV1-7, have been characterised.〔 In 2009, the outbreak of a febrile horse disease across Israel, later diagnosed as EEV, caused great concern primarily due to the similarity of EEV with the African Horse Sickness Virus, one of the most devastating equine pathogens. == Clinical Signs == The name Equine Encephalosis is misleading as the disease is not primarily a neurological disorder. Although the majority of infections result only in mild clinical signs, in more severe cases clinical signs include a short period (typically two to five days) of fluctuating fever, accompanied by varying degrees of inappetence.〔 〕 Elevated heart and respiratory rates are also common, and occasionally as a result of nasal congestion, a red-brown discolouration of the mucous membranes may be observed.〔 Although rare, more severe clinical signs may occur including facial swelling (lips and eyelids), respiratory distress, and petechial haemorrhages of the conjunctivae.〔 Pregnant mares may also abort during their first 5 months of gestation.〔 〕 Neurological signs are atypical, but in certain cases hindquarter ataxia, convulsions, hyperexcitability, and depression have been reported.〔 The mortality rate is normally low, accounting for only 5% of infected animals.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Equine encephalosis virus」の詳細全文を読む スポンサード リンク
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