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锦鲤疱疹病毒病(Koi herpes virus disease,KHVD)是20世纪末被确定的一种疾病,现已流行于世界各地,是严重威胁鲤和锦鲤养殖业安全的一种疾病,世界动物卫生组织(OIE)列为必须申报的疾病,我国将其列为二类疫病。一、病原学病原是锦鲤疱疹病毒(K o i herpes virus,KHV),暂列为疱疹病毒科(Herpesviridae),鲤疱疹病毒属(Cyprinid herpesvirus),又称鲤疱疹病毒Ⅲ型(CyHV-Ⅲ),与鲤痘疮病毒(鲤疱疹病毒Ⅰ型,CyHV-Ⅰ)和金鱼造血器官坏死病毒(鲤疱疹病毒Ⅱ型,CyHV-Ⅱ)同属。KHV和CyHV-Ⅰ存在交叉的抗原反应。KHV是球状病毒,成熟病毒颗粒有囊膜,直径约170nm～230nm。核衣壳为对称十面体,直径100nm～110nm,由31种病毒多肽组成,其中21种多肽分子量与鲤疱疹病毒相似,10种多肽与斑点叉尾鮰病毒(Channel catfish virus,CCV)相似。KHV含有双链DNA,基因组大小约为277kb,比疱疹病毒科的其他病毒基因组(250kb)大。二、流行病学目前该病流行范围已遍及欧亚美非各大洲的以色列、英国、德国、美国、南非、日本、韩国、中国、马来西亚、新加坡、印度尼西亚等国家,并在部分国家造成危害。1998年5月,该病在以色列首次发生,随后18个月内连续发生三次,造成以色列600吨食用普通鲤和400万美元出口锦鲤的损失。使以色列鲤和锦鲤养殖业遭受毁灭性打击。2002年4月印度尼西亚养殖锦鲤和鲤暴发该病,损失500万美元。2003年10月日本10余个县暴发该病,造成近千吨的鲤和锦鲤死亡。KHV的严重危害引起国际动物卫生组织(OIE)和世界粮农组织(FAO)的高度关注。KHV仅仅感染锦鲤、鲤和剃刀鱼(Solenostomus paradoxus)。其鱼苗、幼鱼、成鱼,均可感染。KHV发病最适温度是23℃～28℃(低于18℃,高于30℃不会引起死亡)。若鱼已感染KHV,水温18℃～27℃间持续时间越长,疾病暴发的可能性越大。该病多发于春、秋季,潜伏期14天,鱼发病并出现症状24小时～48小时后开始死亡,开始死亡至2天～4天内死亡率可迅速达80%～100%。KHV暴发后幸存的鱼成为疾病的传播者,可将病毒传染给其他健康的鱼。KHV主要通过水平传播,能否垂直传播目前尚未确定。三、临床症状病鱼停止游泳,鱼眼凹陷,皮肤上出现苍白的块斑与水泡,
Koi herpes virus disease (KHVD), a disease identified in the late 20th century, is now endemic in all parts of the world and is a serious threat to the safety of carp and koi aquaculture. The World Animal Health Organization OIE) must be declared as a disease, our country will be classified as two types of disease. First, pathogenic pathogens are Koi herpes virus (KHV), temporarily classified as herpesviridae, Cyprinid herpesvirus, also known as Cyprinid herpesvirus type III (CyHV-III) (Cyprinus herpesvirus type I, CyHV-I) and goldfish hemorrhage organ necrosis virus (Cyprinid herpesvirus type II, CyHV-II) belong to the same genus. Cross-reactive antigen exists between KHV and CyHV-I. KHV is a spherical virus, mature virus particles capsule, a diameter of about 170nm ~ 230nm. The nucleocapsid is a symmetrical decahedron and has a diameter of 100 nm to 110 nm. It consists of 31 kinds of viral polypeptides, of which 21 are similar in molecular weight to the herpes zoster virus and 10 are similar to the channel catfish virus (CCV). KHV contains double-stranded DNA, the genome size of about 277kb, herpes simplex than the other virus genome (250kb). Epidemiology Currently, the epidemic has spread throughout the Eurasian and non-Central African continent of Israel, Britain, Germany, the United States, South Africa, Japan, South Korea, China, Malaysia, Singapore, Indonesia and other countries, causing harm in some countries. The disease took place for the first time in Israel in May 1998, three consecutive times in the ensuing 18 months, resulting in 600 tons of ordinary carp consumed in Israel and $ 4 million in export koi losses. The Israeli carp and koi aquaculture suffered devastating blows. In April 2002, the Indonesian farmed Koi carp and carp broke out the disease with a loss of 5 million U.S. dollars. In October 2003, more than 10 counties in Japan were outbreaks of the disease, killing nearly a thousand tons of common carps and koi carps. The serious harm of KHV has caused great concern from the International Organization for Animal Health (OIE) and the World Food Program (FAO). KHV infects Koi, Cyprinus carpio and Solenostomus paradoxus only. The fry, juvenile, adult fish, can be infected. KHV incidence of the optimum temperature is 23 ℃ ~ 28 ℃ (below 18 ℃, above 30 ℃ will not cause death). If the fish have been infected with KHV, the longer the water temperature between 18 ℃ ~ 27 ℃, the greater the possibility of disease outbreaks. The disease occurs in spring and autumn, the incubation period of 14 days, the fish onset and symptoms began 24 hours to 48 hours after the start of death, death began to 2 days to 4 days, the mortality rate can be rapidly up to 80% to 100%. Surviving fish after KHV outbreaks become communicators of the disease and can transmit the virus to other healthy fish. KHV mainly through the level of transmission, whether vertical transmission has not yet been determined. Third, the clinical symptoms of sick fish to stop swimming, fisheye depression, pale skin patches and blisters on the skin,