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禽流感是禽流行性感冒的简称。禽流感可分为高致病性、低致病性和非致病性禽流感三大类。非致病性禽流感不会引起明显症状,仅使染病的禽鸟体内产生病毒抗体。低致病性禽流感可使禽类出现轻度呼吸道症状,食量减少,产蛋量下降,出现零星死亡。高致病性禽流感最为严重,发病率和死亡率均高,感染高致病性禽流感死亡率约是60%,家禽鸡感染的死亡率几乎是100%,无一幸免。 相似文献
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陈向英 《新农村(黑龙江)》2013,(16):210-210
禽流感是由A型流感病毒引起的一种禽类传染病。禽流感病毒感染后临床表现多为呼吸道、消化道症状,或全身性、出血性、败血性症状,死亡率较高。根据其病毒致病性和毒力不同,分为高致病性、低致病性和无致病性禽流感。 相似文献
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高致病性禽流感是由H5N1亚型高致病性禽流感病毒感染禽类的一种高度接触性传染病,该病常引起鸡、鸭、鹅及其他易感禽类100%的死亡率。H5N1亚型高致病性禽流感病毒变异株最易感染产蛋鸡,引起产蛋鸡产蛋量明显下降。一些高致病性禽流感还可以直接感染人类,人感染后的症状主要表现为高热、咳嗽、流涕、肌痛等,多数伴有严重的肺炎,严重的会导致心、肾等多种脏器衰竭而死 相似文献
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《农民致富之友》2005,(12):22-22
1、问：什么是禽流感？
杨淑琴：禽流感是禽流行性感冒的简称。高致病性禽流感是一种由A型流感病毒引起的鸡的急性、热性、高度接触性传染性疾病，被世界动物卫生组织定为A类传染病，我国定为一类传染病，又称真性鸡瘟或欧洲鸡瘟。不仅是鸡，其他一些家禽如鸭、鸽和野鸟都能感染禽流感。按病原体的致病特性，禽流感可分为非致病性、低致病性和高致病性3大类。非致病性禽流感不会引起明显症状，仅诱导染病的禽鸟体内产生抗体。低致病性禽流感可使禽类出现轻度呼吸道症状，食量减少、下痢、产蛋量下降，出现零星死亡。高致病性禽流感最为重，通常无典型临床症状，发病急，体温升高，食欲废绝，伴有出血综合症，并随之死亡。死亡率高达100％，给养禽业造成毁灭性的打击。 相似文献
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《广东农村实用技术》2005,(12):30-32
禽流感是禽流行性感冒的简称，是由A型流感病毒引起的一种禽类（家禽和野禽）传染病。禽流感病毒感染后可以表现为轻度的呼吸道症状、消化道症状，死亡率较低；或表现为较严重的全身性、出血性、败血性症状，死亡率较高。根据禽流感病毒致病性和毒力的不同，可以将禽流感分为高致病性禽流感、低致病性禽流感和无致病性禽流感。 相似文献
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《农业工程技术:农产品加工》2004,(1)
一、高致病性禽流感的概念、发病及流行特点禽流感是禽流行性感冒的简称。是由A型禽流行性感冒病毒引起的一种禽类(家禽和野禽)传染病。禽流感病毒感染后可以表现为轻度的呼吸道症状、消化道症状,死亡率较低;或表现为较严重的全身性、出血性、败血性症状,死亡率较高。这种症状上的不同,主要是由禽流感的毒型决定的。根据禽流感致病性的不同,可以将禽流感分为高致病性禽流感、低致病性禽流感和无致病性禽流感。最近国内外由H5N1血清型引起的禽流感称高致病性禽流感,发病率和死亡率都很高,危害巨大。禽流感的传播有病禽和健康禽直接接触和病… 相似文献
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高致病性禽流感的防控 总被引：1，自引：0，他引：1
禽流感是由A型流感病毒引起的一种禽类传染病.禽流感病毒感染后可以表现为轻度的呼吸道、消化道症状,死亡率较低;或表现为较严重的全身性、出血性、败血性症状,死亡率较高.这种症状上的不同,主要是由禽流感病毒的毒力所决定的.根据禽流感病毒致病性和毒力的不同,可以将禽流感分为高致病性禽流感、低致病性禽流感和无致病性禽流感. 相似文献
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正禽流感是由A型流感病毒引起的禽类一种急性传染病,以高热、呼吸困难、全身败血症等为主要特征,具有较高的死亡率。冬季为禽流感高发期,加之春节将至,市场活禽需求量大、跨区域调运频繁,进一步加大了该病的防控难度。1禽流感流行现状禽流感按致病性的不同可分为高致病性、低致病性和非致病性3大类。非致病性禽流感仅使感染的禽体内产生病毒抗体,并没有明显临床症状。低致病性禽流感可使禽出现轻 相似文献
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禽流感与人类健康 总被引：5，自引：0，他引：5
禽流感(avian influenza,AI)是由A型流感病毒(avian influenza virus)引起的一种禽类感染征或疾病综合症,高致病性禽流感(highly pathogenic avian influenza,HPAI)可引起禽类100％的死亡。由于抗原转变和抗原漂移,禽流感病毒是高度可变的。人禽流感是指高致病性禽流感病毒跨越物种界限,引起人类感染的一种新发传染病。目前,全球已发现H5N1、H7N7、H9N2等亚型禽流感病毒可感染人类。但目前还没有发现禽流感病毒具有在人群中相互传播的能力。对禽流感必须采用积极的预防策略。在加强监测的基础上,对家禽采用扑杀和免疫相结合的措施,可以有效地控制禽流感的流行。研制人类流感疫苗,是预防新的流感病毒株的流行的可靠保证。 相似文献
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共表达禽流感病毒HA和NA基因的重组禽痘病毒在SPF鸡的免疫效力试验 总被引：1，自引：0，他引：1
将禽流感病毒A/Goose/Guangdong/3/96(H5N1)毒株的HA和NA2个基因同源重组到禽痘病毒基因组中,获得了能同时高效表达这2种蛋白的重组禽痘病毒(rFPV-HA-NA)。将rFPV-HA-NA经翅膀刺种途径接种8周龄SPF鸡,免疫后4周分别用10LD50的高致病力禽流感病毒(HPAIV)A/Goose/Guangdong/1/96(H5N1)和A/FPV/Rostock/34(H7N1)毒株进行攻击。结果重组禽痘病毒免疫鸡群诱导产生了高水平的抗体,能够完全抵抗H5N1和H7N1亚型病毒的 相似文献
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A recombinant fowlpox virus co-expressing Haemagglutinin(HA)and Neuraminidase(NA)named as rFPV-HA-NA was produced by HA and NA gene of A/Goose/Guangdong/3/96(H5N1)isolate of avian influenza virus recombined into the genome of fowlpox virus. In this study,to evaluate its ability of protecting chickens against challenge with a lethal dose of highly pathogenic isolates of avian influenza virus,eight-week-old specificpathogenic-free(SPF)chickens were vaccinated with recombinant virus or the wildtypefowlpox virus by wing-web puncture. After challenge 4 weeks with 10 LD50 highly pathogenic avian influenza virus H5N1 and H7N1 isolate,all chickens vaccinated with recombinant virus were protected,while the chickens vaccinated with the wildtype fowlpox virus or unvaccinated controls experienced 100% mortality respectively following challenge. This complete protection was accompanied by the high levels of specific antibody response to the respectivecomponents of the recombinant virus. 相似文献
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Airborne transmission of influenza A/H5N1 virus between ferrets 总被引：1，自引：0，他引：1
Herfst S Schrauwen EJ Linster M Chutinimitkul S de Wit E Munster VJ Sorrell EM Bestebroer TM Burke DF Smith DJ Rimmelzwaan GF Osterhaus AD Fouchier RA 《Science (New York, N.Y.)》2012,336(6088):1534-1541
Highly pathogenic avian influenza A/H5N1 virus can cause morbidity and mortality in humans but thus far has not acquired the ability to be transmitted by aerosol or respiratory droplet ("airborne transmission") between humans. To address the concern that the virus could acquire this ability under natural conditions, we genetically modified A/H5N1 virus by site-directed mutagenesis and subsequent serial passage in ferrets. The genetically modified A/H5N1 virus acquired mutations during passage in ferrets, ultimately becoming airborne transmissible in ferrets. None of the recipient ferrets died after airborne infection with the mutant A/H5N1 viruses. Four amino acid substitutions in the host receptor-binding protein hemagglutinin, and one in the polymerase complex protein basic polymerase 2, were consistently present in airborne-transmitted viruses. The transmissible viruses were sensitive to the antiviral drug oseltamivir and reacted well with antisera raised against H5 influenza vaccine strains. Thus, avian A/H5N1 influenza viruses can acquire the capacity for airborne transmission between mammals without recombination in an intermediate host and therefore constitute a risk for human pandemic influenza. 相似文献
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Liu J Xiao H Lei F Zhu Q Qin K Zhang XW Zhang XL Zhao D Wang G Feng Y Ma J Liu W Wang J Gao GF 《Science (New York, N.Y.)》2005,309(5738):1206
H5N1 avian influenza virus (AIV) has emerged as a pathogenic entity for a variety of species, including humans, in recent years. Here we report an outbreak among migratory birds on Lake Qinghaihu, China, in May and June 2005, in which more than a thousand birds were affected. Pancreatic necrosis and abnormal neurological symptoms were the major clinical features. Sequencing of the complete genomes of four H5N1 AIV strains revealed them to be reassortants related to a peregrine falcon isolate from Hong Kong and to have known highly pathogenic characteristics. Experimental animal infections reproduced typical highly pathogenic AIV infection symptoms and pathology. 相似文献
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Lyall J Irvine RM Sherman A McKinley TJ Núñez A Purdie A Outtrim L Brown IH Rolleston-Smith G Sang H Tiley L 《Science (New York, N.Y.)》2011,331(6014):223-226
Infection of chickens with avian influenza virus poses a global threat to both poultry production and human health that is not adequately controlled by vaccination or by biosecurity measures. A novel alternative strategy is to develop chickens that are genetically resistant to infection. We generated transgenic chickens expressing a short-hairpin RNA designed to function as a decoy that inhibits and blocks influenza virus polymerase and hence interferes with virus propagation. Susceptibility to primary challenge with highly pathogenic avian influenza virus and onward transmission dynamics were determined. Although the transgenic birds succumbed to the initial experimental challenge, onward transmission to both transgenic and nontransgenic birds was prevented. 相似文献
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Reassortant virus derived from avian and human influenza A viruses is attenuated and immunogenic in monkeys 总被引：9，自引：0，他引：9
B R Murphy D L Sly E L Tierney N T Hosier J G Massicot W T London R M Chanock R G Webster V S Hinshaw 《Science (New York, N.Y.)》1982,218(4579):1330-1332
An influenza A reassortant virus that contained the hemagglutinin and neuraminidase genes of a virulent human virus, A/Udorn/72 (H3N2), and the six other influenza A virus genome segments from an avirulent avian virus, A/Mallard/New York/6750/78 (H2N2), was evaluated for its level of replication is squirrel monkeys and hamsters. In monkeys, the reassortant virus was as attenuated and as restricted in its level of replication in the upper and lower respiratory tract as its avian influenza virus parent. Nonetheless, infection with the reassortant induced significant resistant to challenge with virulent human influenza virus. In hamsters, the reassortant virus replicated to a level intermediate between that of its parents. These findings suggest that the nonsurface antigen genes of the avian parental virus are the primary determinants of restriction of replication of the reassortant virus in monkeys. Attenuation of the reassortant virus for primates is achieved by inefficient functioning of the avian influenza genes in primate cells, while antigenic specificity of the human influenza virus is provided by the neuraminidase and hemagglutinin genes derived from the human virus. This approach could lead to the development of a live influenza A virus vaccine that is attenuated for man if the avian influenza genes are similarly restricted in human cells. 相似文献
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禽流感病毒可感染许多鸟类和哺乳动物,但是其自然宿主范围通常限于野生水禽,如野鸭、海鸥等。近年来出现新的特征,可以感染人类、猫、虎等动物,突破了宿主限制性,出现种间传播。这与其宿主特异性变化和致病力变异有关。为此,依据禽流感病毒的致病特性、抗原蛋白(血凝素蛋白HA)特性和宿主细胞受体特点,结合其它影响因素,阐述了流感病毒的宿主特异性和致病性分子基础,以进一步认识禽流感病毒。 相似文献
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