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Schmallenberg virus is the informal name given to a recently isolated orthobunyavirus, which has not been given a formal name , initially reported in November 2011 to cause congenital malformations and stillbirths in cattle, sheep, goats, and possibly alpaca. It appears to be transmitted by midges (''Culicoides'' spp.) which are likely to have been most active in causing the infection in the northern hemisphere summer and autumn of 2011, with animals subsequently giving birth from late 2011.〔 Schmallenberg virus falls in the Simbu serogroup of Orthobunyaviruses; as of January 2013, it is considered to be most closely related to the Sathuperi and Douglas viruses. The virus is named after Schmallenberg, in North Rhine-Westphalia, Germany, from where the first definitive sample was derived.〔 After Germany, it has also been detected in the Netherlands, Belgium, France, Luxembourg, Italy, Spain, the United Kingdom,〔 Switzerland, Ireland, Finland, Denmark, Sweden, Austria,〔 Norway,〔 Poland〔 and Estonia.〔 The virus has been recognised by the European Commission's Standing Committee on the Food Chain and Animal Health〔 and the Friedrich-Loeffler-Institut (German Research Institute for Animal Health).〔(Schmallenberg virus: new Orthobunyavirus in cattle ), updated 10 January 2012, accessed 16 January 2012〕 A risk assessment in December 2011 did not consider it likely to be a threat to human health,〔(Risk assessment: New Orthobunyavirus isolated from infected cattle and small livestock ─ potential implications for human health ), European Centre for Disease Prevention and Control, 22 December 2011, accessed 17 January 2012〕 as other comparable viruses are not zoonotic.〔 Immunity can possibly be acquired naturally against SBV. It is possible that the seasonality of the infection cycle would not entail a second epidemic circulation next year, due to the shortness of the viraemic period (about 4 to 6 days post exposure, longer in affected foetuses). Vaccination is a possible option for controlling the disease as a vaccine exists for the similar Akabane virus.〔(SMC(UK) Fact Sheet on Schmallenberg virus )〕 In March 2012, scientists of the Friedrich-Loeffler-Institut first succeeded in producing an electron microscope image of the Schmallenberg virus.〔(FLI: First visualization of Schmallenberg virus )〕 ==Signs of disease== The virus causes two different profiles of Schmallenberg: *Fever of short duration, diarrhoea and reduced production of milk in cows These disease signs have occurred during the period when the disease vectors (mosquitos, sandflies, midges) are active, during the summer and autumn of 2011, mainly affecting cattle. *Stillbirths and birth defects in sheep, cattle and goats Congenital malformations in newborn sheep, goats and calves are the most obvious symptoms. In many cases, the dam apparently has not presented signs of illness. These cases have occurred from December 2011, especially in sheep. The major malformations observed were: scoliosis, hydrocephalus, arthrogryposis, hypoplasia of the cerebellum and an enlarged thymus. 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「Schmallenberg virus」の詳細全文を読む スポンサード リンク
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