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Foot-and-mouth disease or hoof-and-mouth disease (''Aphthae epizooticae'') is an infectious and sometimes fatal viral disease that affects cloven-hoofed animals, including domestic and wild bovids. The virus causes a high fever for two or six days, followed by blisters inside the mouth and on the feet that may rupture and cause lameness. Foot-and-mouth disease (FMD) has severe implications for animal farming, since it is highly infectious and can be spread by infected animals through aerosols, through contact with contaminated farming equipment, vehicles, clothing, or feed, and by domestic and wild predators.〔 Its containment demands considerable efforts in vaccination, strict monitoring, trade restrictions, and quarantines, and occasionally the killing of animals. Susceptible animals include cattle, water buffalo, sheep, goats, pigs,〔(【引用サイトリンク】title=PLOS ONE )〕 antelope, deer, and bison. It has also been known to infect hedgehogs and elephants;〔(Canadian Food Inspection Agency - Animal Products - Foot-and-Mouth Disease Hazard Specific Plan )〕 llamas and alpacas may develop mild symptoms, but are resistant to the disease and do not pass it on to others of the same species.〔 In laboratory experiments, mice, rats, and chickens have been successfully infected by artificial means, but they are not believed to contract the disease under natural conditions.〔 Humans are very rarely infected. The virus responsible for the disease is a picornavirus, the prototypic member of the genus ''Aphthovirus''. Infection occurs when the virus particle is taken into a cell of the host. The cell is then forced to manufacture thousands of copies of the virus, and eventually bursts, releasing the new particles in the blood. The virus is genetically highly variable, which limits the effectiveness of vaccination. ==History== The cause of FMD was first shown to be viral in 1897 by Friedrich Loeffler. He passed the blood of an infected animal through a Chamberland filter and found the collected fluid could still cause the disease in healthy animals. FMD occurs throughout much of the world, and while some countries have been free of FMD for some time, its wide host range and rapid spread represent cause for international concern. After World War II, the disease was widely distributed throughout the world. In 1996, endemic areas included Asia, Africa, and parts of South America; as of August 2007, Chile is disease-free, and Uruguay and Argentina have not had an outbreak since 2001. In May 2014, the FAO informed that Bolivia, Colombia, Ecuador and Peru were "just one step away" from eradication;〔(【引用サイトリンク】title=Latest swine news : FAO: Andean countries short of eradicating the foot-and-mouth disease - pig333, pig to pork community )〕 North America and Australia have been free of FMD for many years. New Zealand has never had a case of foot-and-mouth disease. Most European countries have been recognized as disease-free, and countries belonging to the European Union have stopped FMD vaccination. However, in 2001, a serious outbreak of FMD in Britain resulted in the slaughter of many animals, the postponing of the general election for a month, and the cancellation of many sporting events and leisure activities, such as the Isle of Man TT. Due to strict government policies on sale of livestock, disinfection of all persons leaving and entering farms, and the cancellation of large events likely to be attended by farmers, a potentially economically disastrous epizootic was avoided in the Republic of Ireland, with just one case recorded in Proleek, Co. Louth. In August 2007, FMD was found at two farms in Surrey, England. All livestock were culled and a quarantine erected over the area. Two other suspected outbreaks have occurred since, although these seem now not to be related to FMD. The only reported case in 2010 was a false alarm from GIS Alex Baker, as proven false by the Florida Farm and Agricultural Department, and the confirmed quarantine/slaughter of cattle and pigs was reported from Miyazaki Prefecture in Japan in June after three cows tested positive. A total of some 270,000 cattle have been ordered slaughtered following the disease's outbreak. 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「Foot-and-mouth disease」の詳細全文を読む スポンサード リンク
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