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·高被引论文摘要·

2017-01-26

中国学术期刊文摘 2017年5期

·高被引论文摘要·

被引频次:96

浙江省人感染H7N9禽流感流行特征与防控对策

陈恩富,柴程良,孙继民

目的:分析人感染H7N9禽流感的流行特征、研究进展和目前防控面临的问题,提出防控对策。方法:采用流行病学个案调查与描述性分析方法,收集人感染H7N9禽流感确诊病例流行病学和防控措施相关资料,分析病例流行病学特征和疫情防控措施效果。结果浙江省共确诊人感染H7N9禽流感病例44例,死亡6例;男性27例,占61.36%;平均年龄60.18岁(32~86岁);≥50岁35例,占79.55%;农民和离退人员30例,占68.18%。40例(90.91%)集中于杭州和湖州。78.38%(29/37)有慢性基础性疾病,78.95%(30/38)发病前有禽类暴露史;病例的1004名密切接触者均未发现感染。病例可疑暴露场所外环境标本H7N9阳性率高达43.21%(35/81)。暂停市场活禽交易对控制疫情有效。结论:人感染H7N9禽流感流行特征尚未完全明了,需要多部门联合开展监测、研究和防控。

人感染H7N9禽流感;流行病学;控制策略

来源出版物:中国公共卫生, 2013, 29(5): 625-627

被引频次:48

H7亚型禽流感病毒概述

朱闻斐,高荣保,王大燕,等

摘要:自2002年以来,全球报道的人感染H7亚型禽流感病毒病例超过100人,波及荷兰、意大利、加拿大、美国以及英国等国家。人感染H7亚型禽流感病毒的临床表现由结膜炎至轻微的上呼吸道疾病,甚至是肺炎。2013年3月31日,中国报道了上海市和安徽省两地共3例H7N9亚型禽流感病毒(AIVs)感染死亡病例。由于从家禽中分离到的H7亚型流感病毒不断增加,

而且H7亚型AIVs感染人所导致的严重的临床症状,因此该亚型流感病毒对人类健康造成严重威胁,所以我们必须提高对H7亚型AIVs的认识,并要加强人群和动物中流感病毒的持续监测以及疫苗和药物的研究,以应对可能由于H7亚型AIVs引起的流感大流行。

关键词:H7亚型禽流感病毒;人感染H7亚型;H7N9;H7病原学特征

来源出版物:病毒学报, 2013, 29(3): 245-249

被引频次:45

科学认识H7N9,有效防控人感染禽流感病毒

毛青

摘要:自2013年2月以来,华东地区上海市、安徽省、江苏省、浙江省先后发生不明原因重症肺炎病例,大多数患者病前曾有活禽鸟接触史,经病原体分离鉴定后,于3月31日将其确诊为人感染H7N9禽流感病毒(avian influenza virus,AIV)。截止到2013年4月15日共确诊病例63例,死亡14例。目前病例均为散发,并未见人际间传播。

关键词:H7N9;人;感染;禽流感;病毒

来源出版物:第三军医大学学报, 2013, 35(8): 693-695

被引频次:43

中国大陆130例人感染H7N9禽流感病例流行病学特征分析

闫铁成,肖丹,王波

摘要:目的:描述和分析人感染H7N9禽流感病例的流行病学分布特征,为该传染病的防控提供科学依据。方法:收集中国大陆2013年3月30日—5月20日期间报告的人感染H7N9禽流感确诊病例130例,利用χ2检验、线性趋势检验和空间自相关分析,描述并分析病例的三间分布特征。结果:130例确诊病例中,报告发病时间的104例,同时报告发病时间和确诊时间的103例。死亡病例36例,其中,同时报告发病时间和死亡时间的21例。首例病例发生于2月19日,末例病例发生于5月3日,病例的发病高峰出现在3月末至4月中旬。21例病例发病至死亡的平均时间为(16±8)d(6~36 d),103例病例发病至确诊的平均时间为(9±5)d(1~39 d),发病至确诊的平均时间呈下降趋势(F= 37.56,P<0.001)。确诊病例中,男性、50岁及以上者居多,分别占69.6%(87/125)和72.8%(91/125)。病例分布于中国10个省(直辖市),存在空间自相关性(Z=3.90,P= 0.001),浙江、上海、江苏3个省(直辖市)报告的病例总数占病例总数的81.5%。结论男性、中老年是人感染H7N9禽流感的主要易感人群。我国东南沿海是人禽流感的重点监测地区。

关键词:禽流感;流行病学;性别分布

来源出版物:中华疾病控制杂志, 2013, 17(8): 651-654

被引频次:38

国内102例人感染H7N9禽流感特点初步分析

韩明锋,冉献贵,赵凤德

摘要:目的:初步总结人感染H7N9禽流感的特点。方法:利用目前国家和各省市卫生部门及国家媒体网站公布的人感染H7N9禽流感病例的有关资料,用描述性分析方法,总结该病的流行病学和临床特点。结果:人感染H7N9禽流感传染源可能为携带H7N9禽流感病毒的禽类。目前尚未发现人传人的情况。人发病一般表现为流感样症状,但是重症患者病情发展迅速,多在5~7 d出现重症肺炎,病死率较高。用神经氨酸酶抑制剂早期抗病毒治疗有效。结论:人感染H7N9禽流感是人类新发传染病,病情较凶险。应重视动物和人间疫情防控以及疾病的早发现、早诊断、早治疗。

关键词:流感病毒A型,H7N9亚型;禽流感;流行病学;疾病特征

来源出版物:传染病信息, 2013 (2): 68-70

被引频次:36

H7N9病毒的来源和重组模式

张宝,黄克勇,郭劲松,等

摘要:目的:通过序列分析揭示H7N9病毒的来源和重组产生模式。方法:收集H7N9序列,运用BLAST、MEGA5.0等生物信息学软件分析序列相似性、多序列比对、构建进化树,确定H7N9病毒各节段序列的亲缘序列,模拟H7N9重组产生方式。结果:系统进化树显示HA、NA、PB2和NS节段最近缘关系序列只有一个;而PB1、PA、NP和MP节段序列,分布于不同的两个分枝。通过组合分析亲缘序列,可以将目前流行的H7N9病毒分为5型:A、B、A/Shanghai/1/2013-H7N9、A/Pigeon/Shanghai/S1069-H7N9和A/Zhejiang/HZ1/2013-H7N9。A型又可以分为A1和A2亚型。结论:通过对序列的组合分析,推测此次H7N9病毒流行至少由5个病毒经过4次重组产生,产生两个主要流行株A和B型。A1和A2亚型的出现是同一次重组过程中产生两株不同产物;A/Pigeon/Shanghai/S1069-H7N9是A型H7N9病毒在流行期间与当地H9N2病毒的再一次重组产生。A/Zhejiang/HZ1/2013-H7N9是A2亚型和B型重组后产生的混合型。

关键词:H7N9;禽流感;重组;生物信息学

来源出版物:南方医科大学学报, 2013, 33(7): 1017-1021

被引频次:21

H7N9禽流感病毒研究现状

江丽芳

摘要:2013年3月在中国华东地区爆发了一场严重的人类感染禽流感疫情,导致此次疫情的病原体为一种全新的H7N9禽流感病毒,该病毒以其对人类的高致病性及远高于H5N1禽流感病毒的传播速度而引起全球广泛关注。本文就H7N9禽流感病毒的病原学、致病的分子基础、流行病学、临床特征及防治措施等方面的研究现状进行综述,旨在了解人感染H7N9禽流感的研究进展,为人感染H7N9禽流感的有效防控提供科学依据。

关键词:H7N9禽流感病毒;病原学;流行病学;致病性;临床特征;防治措施

来源出版物:中山大学学报:医学科学版, 2013, 34(5): 651-656

被引频次:19

人感染H7N9禽流感流行特征与防控策略

陈健,毛盛华,胡家瑜,等

摘要:2013年3月31日中国大陆出现新型禽流感疫情,此次的H7N9禽流感病毒为全球首次发现的新亚型流感病毒,可能由3种流感病毒重组后产生。截至5月31日,我国内地共报告确诊病例131例,死亡39例。而在上海市报告的33例确诊病例中,29例发病于4月6日上海市关闭活禽交易市场前,其余4例发病于关闭后的第一个潜伏期内。33例病例中60岁以上患者占66.7%(22/33);15例死亡病例中,60岁以上患者占80%(12/15);90.91%(30/33)的病例具有可疑的动物或环境暴露史。此次疫情呈散发,虽然出现了2起家庭聚集性病例,但目前还没有明确的人传人的证据。疫情发生后,上海市人民政府适时启动了流感流行应急预案Ⅲ级响应,通过突发公共卫生事件应急响应、关闭全市活禽交易、健康教育、风险沟通等手段,及时有效地控制了疾病的传播。本文分析这次疫情防控工作的得失并提出建议,供今后的防疫工作借鉴参考。

关键词:禽流感;H7N9亚型流感病毒A型;流行病学;传染病控制

来源出版物:第二军医大学学报, 2013, 34(6): 585-590

被引频次:19

杭州市下城区4例人感染H7N9禽流感病例的临床与流行病学特征分析

寿钧,周晓红,何玉芳,等

摘要:目的:对杭州市下城区2013年确诊报告的4例人感染H7N9禽流感病例进行临床和流行病学分析,为进一步科学防控人禽流感提供依据。方法:对确诊病例和病例的密切接触者进行个案调查,采用荧光双标记探针反转录-聚合酶链反应检测H7N9禽流感病毒。对病例的呼吸道标本进行人感染H7N9禽流感病毒核酸检测。结果:4例病例表现为重症肺炎并呈进行性加重,

发病至首次就诊平均时间为2 d,首次住院为5 d,确诊时间为7 d。4病例呈高度散发,病例之间无流行病学关联,发病时间均为春季,均有农贸市场暴露史。对病例采取隔离治疗、密切接触者进行医学观察、疫点终末消毒、农贸市场停止活禽交易等综合措施后,疫情得到有效控制。结论:4例人感染高H7N9禽流感病例发病与农贸市场暴露有关,暂未发现人传人的证据。早期发现和救治患者是提高患者预后的关键,要加强人感染H7N9禽流感疫情监测,及时科学处置疫情,以控制疫情扩散。

关键词:人感染H7N9禽流感;临床;流行病学

来源出版物:疾病监测, 2013, 28(8): 657-659

被引频次:17

H7N9禽流感病毒感染及其实验室诊断

董晓毅,孙长贵

摘要:至2013年4月23日,新型H7N9亚型的禽流感病毒已经在中国感染了108人,并致22人死亡。科学家发现甲型禽流感病毒H7N9源自3种病毒株的重配,并出现了实质性的突变。H7N9病毒拥有几个哺乳动物流感病毒的特征,从而形成了对人类的感染力,因此需重视其大规模流行的潜力。本文对该病毒的生物学特性、流行病学、临床表现和实验室诊断进行了简要综述。

关键词:H7N9;禽流感病毒;感染

来源出版物:实验与检验医学, 2013, 31(2): 105-107

被引频次:986

来源出版物:New England Journal of Medicine, 2013, 368(20): 1888-1897

被引频次:377

Human infections with the emerging avian influenza A H7N9 virus from wet market poultry: Clinical analysis and characterisation of viral genome

Chen, Y; Liang, WF; Yang, SG; et al.

Abstract: Background: Human infection with avian influenza A H7N9 virus emerged in eastern China in February, 2013, and has been associated with exposure to poultry. We report the clinical and microbiological features of patients infected with influenza A H7N9 virus and compare genomic features of the human virus with those of the virus in market poultry in Zhejiang, China. Methods: Between March 7 and April 8, 2013, we included hospital inpatients if they had new-onset respiratory symptoms, unexplained radiographic infiltrate, and laboratory-confirmed H7N9 virus infection. We recorded histories and results of haematological, biochemical, radiological, and microbiological investigations. We took throat and sputum samples, used RT-PCR to detect M, H7, and N9 genes, and cultured samples in Madin-Darby canine kidney cells. We tested for co-infections and monitored serum concentra- tions of six cytokines and chemokines. We collected cloacal swabs from 86 birds from epidemiologically linked wet markets and inoculated embryonated chicken eggs with the samples. We identified and subtyped isolates by RT-PCR sequencing. RNA extraction, complementary DNA synthesis, and PCR sequencing were done for one human and one chicken isolate. We characterised and phylogenetically analysed the eight gene segments of the viruses in the patient's and the chicken's isolates, and constructed phylogenetic trees of H, N, PB2, and NS genes. Findings: We identified four patients (mean age 56 years), all of whom had contact with poultry 3-8 days before disease onset. They presented with fever and rapidly progressive pneumonia that did not respond to antibiotics. Patients were leucopenic and lymphopenic, and had impaired liver or renal function, substantially increased serum cytokine or chemokine concentrations, and disseminated intravascular coagulation with disease progression. Two patients died. Sputum specimens were more likely to test positive for the H7N9 virus than were samples from throat swabs. The viral isolate from the patient was closely similar to that from an epidemiologically linked market chicken. All viral gene segments were of avian origin. The H7 of the isolated viruses was closest to that of the H7N3 virus from domestic ducks in Zhejiang, whereas the N9 was closest to that of the wild bird H7N9 virus in South Korea. We noted Gln226Leu and Gly186Val substitutions in human virus H7 (associated with increased affinity for alpha-2,6-linked sialic acid receptors) and the PB2 Asp701Asn mutation (associated with mammalian adaptation). Ser31Asn mutation, which is associated with adamantane resistance, was noted in viral M2. Interpretation: Cross species poultry-to-person transmission of this new reassortant H7N9 virus is associated with severe pneumonia and multiorgan dysfunction in human beings. Monitoring of the viral evolution and further study of disease pathogenesis will improve disease management, epidemic control, and pandemic preparedness.

来源出版物:The Lancet, 2013, 381(9881): 1916-1925

被引频次:255

Clinical findings in 111 cases of influenza A (H7N9) virus infection

Gao, HN; Lu, HZ; Cao, B; et al.

Abstract: Background: During the spring of 2013, a novel avian-origin influenza A (H7N9) virus emerged and spread among humans in China. Data were lacking on the clinical characteristics of the infections caused by this virus. Methods: Using medical charts, we collected data on 111 patients with laboratory-confirmed avian-origin influenza A (H7N9) infection through May 10, 2013. Results: Of the 111 patients we studied, 76.6% were admitted to an intensive care unit (ICU), and 27.0% died. The median age was 61 years, and 42.3% were 65 years of age or older; 31.5% were female. A total of 61.3% of the patients had at least one underlying medical condition. Fever and cough were the most common presenting symptoms. On admission, 108 patients (97.3%) had findings consistent with pneumonia. Bilateral ground-glass opacities and consolidation were the typical radiologic findings. Lymphocytopenia was observed in 88.3% of patients, and thrombo-cytopenia in 73.0%. Treatment with antiviral drugs was initiated in 108 patients (97.3%) at a median of7 days after the onset of illness. The median times from the onset of illness and from the initiation of antiviral therapy to a negative viral test result on real-time reversetranscriptase-polymerase-chain-reaction assay were 11 days (interquartile range, 9 to 16) and 6 days (interquartile range, 4 to 7), respectively. Multivariate analysis revealed that the presence of a coexisting medical condition was the only independent risk factor for the acute respiratory distress syndrome (ARDS) (odds ratio, 3.42; 95% confidence interval, 1.21 to 9.70; P = 0.02). Conclusions: During the evaluation period, the novel H7N9 virus caused severe illness, including pneumonia and ARDS, with high rates of ICU admission and death.

来源出版物:New England Journal of Medicine, 2013, 368(24): 2277-2285

被引频次:255

Origin and diversity of novel avian influenza A H7N9 viruses causing human infection: Phylogenetic, structural, and coalescent analyses

Liu, D; Shi, WF; Shi, Y; et al.

Abstract: Background: On March 30, 2013, a novel avian influenza A H7N9 virus that infects human beings was identified. This virus had been detected in six provinces and municipal cities in China as of April 18, 2013. We correlated genomic sequences from avian influenza viruses with ecological information and did phylogenetic and coalescent analyses to extrapolate the potential origins of the virus and possible routes of reassortment events. Methods: We downloaded H7N9 virus genome sequences from the Global Initiative on Sharing Avian Influenza Data (GISAID) database and public sequences used from the Influenza Virus Resource. We constructed phylogenetic trees and did 1000 bootstrap replicates for each tree. Two rounds of phylogenetic analyses were done. We used at least 100 closely related sequences for each gene to infer the overall topology, removed suspicious sequences from the trees, and focused on the closest clades to the novel H7N9 viruses. We compared our tree topologies with those from a bayesian evolutionary analysis by sampling trees (BEAST) analysis. We used the bayesian Markov chain Monte Carlo method to jointly estimate phylogenies, divergence times, and other evolutionary parameters for all eight gene fragments. We used sequence alignment and homology-modelling methods to study specific mutations regarding phenotypes, specifically addressing the human receptor binding properties. Findings: The novel avian influenza A H7N9 virus originated from multiple reassortment events. The HA gene might have originated from avian influenza viruses of duck origin, and the NA gene might have transferred from migratory birds infected with avian influenza viruses along the east Asian flyway. The six internal genes of this virus probably originated from two different groups of H9N2 avian influenza viruses, which were isolated from chickens. Detailed analyses also showed that ducks and chickens probably acted as the intermediate hosts leading to the emergence of this virulent H7N9 virus. Genotypic and potential phenotypic differences imply that the isolates causing this outbreak form two separate subclades. Interpretation: The novel avian influenza A H7N9 virus might have evolved from at least four origins. Diversity among isolates implies that the H7N9 virus has evolved into at least two different lineages. Unknown intermediate hosts involved might be implicated, extensive global surveillance is needed, and domestic-poultry-to-person transmission should be closely watched in the future.

来源出版物:The Lancet, 2013, 381(9881): 1926-1932

被引频次:235

Epidemiology of human infections with avian influenza A (H7N9) virus in China

Li, Q; Zhou, L; Zhou, MH; et al.

Abstract: Background: The first identified cases of avian influenza A (H7N9) virus infection in humans occurred in China during February and March 2013. We analyzed data obtained from field investigations to describe the epidemiologic characteristics of H7N9 cases in China identified as of December 1, 2013. Methods: Field investigations were conducted for each confirmed case of H7N9 virus infection. A patient was considered to have a confirmed case if the presence of the H7N9 virus was verified by means of real-time reverse-transcriptasepolymerase-chain-reaction assay (RT-PCR), viral isolation, or serologic testing. Information on demographic characteristics, exposure history, and illness timelines was obtained from patients with confirmed cases. Close contacts were monitored for 7 days for symptoms of illness. Throat swabs were obtained from contacts inwhom symptoms developed and were tested for the presence of the H7N9 virus by means of real-time RT-PCR. Results: Among 139 persons with confirmed H7N9 virus infection, the median age was 61 years (range, 2 to 91), 71% were male, and 73% were urban residents. Confirmed cases occurred in 12 areas of China. Nine persons were poultry workers, and of 131 persons with available data, 82% had a history of exposure to live animals, including chickens (82%). A total of 137 persons (99%) were hospitalized, 125 (90%) had pneumonia or respiratory failure, and 65 of 103 with available data (63%) were admitted to an intensive care unit. A total of 47 persons (34%) died in the hospital after a median duration of illness of 21 days, 88 were discharged from the hospital, and 2 remain hospitalized in critical condition; 2 patients were not admitted to a hospital. In four family clusters, human-to-human transmission of H7N9 virus could not be ruled out. Excluding secondary cases in clusters, 2675 close contacts of case patients completed the monitoring period; respiratory symptoms developed in 28 of them (1%); all tested negative for H7N9 virus. Conclusions: Most persons with confirmed H7N9 virus infection had severe lower respiratory tract illness, were epidemiologically unrelated, and had a history of recent exposure to poultry. However, limited, nonsustained human-to-human H7N9 virus transmission could not be ruled out in four families.

来源出版物:New England Journal of Medicine, 2014, 370(6): 520-532

被引频次:186

Characterization of H7N9 influenza A viruses isolated from humans

Watanabe, T; Kiso, M; Fukuyama, S; et al.

Abstract: Avian influenza A viruses rarely infect humans; however, when human infection and subsequent human-tohuman transmission occurs, worldwide outbreaks (pandemics) can result. The recent sporadic infections of humans in China with a previously unrecognized avian influenza A virus of the H7N9 subtype (A(H7N9)) have caused concern owing to the appreciable case fatality rate associated with these infections (more than 25%), potential instances of human-to-human transmission(1), and the lack of pre-existing immunity among humans to viruses of this subtype. Here we characterize two early human A(H7N9) isolates, A/Anhui/1/2013 (H7N9) and A/Shanghai/1/2013 (H7N9); hereafter referred to as Anhui/1 and Shanghai/1, respectively. In mice, Anhui/1 and Shanghai/1 were more pathogenic than a control avian H7N9 virus (A/duck/Gunma/466/2011 (H7N9); Dk/GM466) and a representative pandemic 2009 H1N1 virus (A/California/4/2009 (H1N1pdm09); CA04). Anhui/1, Shanghai/1 and Dk/GM466 replicated well in the nasal turbinates of ferrets. In nonhuman primates, Anhui/1 and Dk/GM466 replicated efficiently in the upper and lower respiratory tracts, whereas the replicative ability of conventional human influenza viruses is typically restricted to the upper respiratory tract of infected primates. By contrast, Anhui/1 did not replicate well in miniature pigs after intranasal inoculation. Critically, Anhui/1 transmitted through respiratory droplets in one of three pairs of ferrets. Glycan arrays showed that Anhui/1, Shanghai/1 and A/Hangzhou/1/2013 (H7N9) (a third human A(H7N9) virus tested in this assay) bind to human virus-type receptors, a property that may be critical for virus transmissibility in ferrets. Anhui/1 was found to be less sensitive in mice to neuraminidase inhibitors than a pandemic H1N1 2009 virus, although both viruses were equally susceptible to an experimental antiviral polymerase inhibitor. The robust replicative ability in mice, ferrets and nonhuman primates and the limited transmissibility in ferrets of Anhui/1 suggest that A(H7N9) viruses have pandemic potential.

来源出版物:Nature, 2013, 501(7468): 551-555

被引频次:181

The genesis and source of the H7N9 influenza viruses causing human infections in China

Lam, TTY; Wang, J; Shen, YY; et al.

Abstract: A novel H7N9 influenza A virus first detected in March 2013 has since caused more than 130 human infections in China, resulting in 40 deaths(1,2). Preliminary analyses suggest that the virus is a reassortant of H7, N9 and H9N2 avian influenza viruses, and carries some amino acids associated with mammalian receptor binding, raising concerns of a new pandemic(1,3,4). However, neither the source populations of the H7N9 outbreak lineage nor the conditions for its genesis are fully known(5). Using a combination of active surveillance, screening of virus archives, and evolutionary analyses,here we show that H7 viruses probably transferred from domestic duck to chicken populations in China on at least two independent occasions. We show that the H7 viruses subsequently reassorted with enzootic H9N2 viruses to generate the H7N9 outbreak lineage, and a related previously unrecognized H7N7 lineage. The H7N9 outbreak lineage has spread over a large geographic region and is prevalent in chickens at live poultry markets, which are thought to be the immediate source of human infections. Whether the H7N9 outbreak lineage has, or will, become enzootic in China and neighbouring regions requires further investigation. The discovery here of a related H7N7 influenza virus in chickens that has the ability to infect mammals experimentally, suggests that H7 viruses may pose threats beyond the current outbreak. The continuing prevalence of H7 viruses in poultry could lead to the generation of highly pathogenic variants and further sporadic human infections, with a continued risk of the virus acquiring human-to-human transmissibility.

来源出版物:Nature, 2013, 502(7470): 241-244

被引频次:178

Clinical and epidemiological characteristics of a fatal case of avian influenza A H10N8 virus infection : A descriptive study

Chen, HY; Yuan, H; Gao, RB; et al.

Abstract: Background: Human infections with different avian influenza viruses-eg, H5N1, H9N2, and H7N9-have raised concerns about pandemic potential worldwide. We report the first human infection with a novel reassortant avian influenza A H10N8 virus. Methods: We obtained and analysed clinical, epidemiological, and virological data from a patient from Nanchang City, China. Tracheal aspirate specimens were tested for influenza virus and other possible pathogens by RT-PCR, viral culture, and sequence analyses. A maximum likelihood phylogenetic tree was constructed. Findings: A woman aged 73 years presented with fever and was admitted to hospital on Nov 30, 2013. She developed multiple organ failure and died 9 days after illness onset. A novel reassortant avian influenza A H10N8 virus was isolated from the tracheal aspirate specimen obtained from the patient 7 days after onset of illness. Sequence analyses revealed that all the genes of the virus were of avian origin, with six internal genes from avian influenza A H9N2 viruses. The aminoacid motif GlnSerGly at residues 226-228 of the haemagglutinin protein indicated avian-like receptor binding preference. A mixture of glutamic acid and lysine at residue 627 in PB2 protein-which is associated with mammalian adaptation- was detected in the original tracheal aspirate samples. The virus was sensitive to neuraminidase inhibitors. Sputum and blood cultures and deep sequencing analysis indicated no co-infection with bacteria or fungi. Epidemiological investigation established that the patient had visited a live poultry market 4 days before illness onset. Interpretation: The novel reassortant H10N8 virus obtained is distinct from previously reported H10N8 viruses. The virus caused human infection and could have been associated with the death of a patient.

来源出版物:The Lancet, 2014, 383(9918): 714-721

被引频次:171

Genetic analysis of novel avian A (H7N9) influenza viruses isolated from patients in China, February to April 2013

Kageyama, T; Fujisaki, S; Takashita, E; et al.

Abstract: Novel influenza viruses of the H7N9 subtype have infected 33 and killed nine people in China as of 10 April 2013. Their haemagglutinin (HA) and neuraminidase genes probably originated from Eurasian avian influenza viruses; the remaining genes are closely related to avian H9N2 influenza viruses. Several characteristic amino acid changes in HA and the PB2 RNA polymerase subunit probably facilitate binding to human-type receptors and efficient replication in mammals, respectively, highlighting the pandemic potential of the novel viruses. Humans are rarely infected with avian influenza viruses, with the exception of highly pathogenic avian influenza A(H5N1) viruses, which have caused 634 infections and 371 deaths as of 12 March 2013. A few isolated cases of human infection with viruses of the H7N2, H7N3, and H7N5 subtypes have been reported, but none were fatal. In 2003, in the Netherlands, 89 people were infected with an influenza virus of the H7N7 subtype that caused conjunctivitis and one fatality. On 19 February 2013, an 87 year-old man in Shanghai developed a respiratory infection and died on 4 March, and on 27 February 2013, a 27 year-old pork seller in a Shanghai market became ill and died on 10 March. A 35 year-old woman in ChuzhouCity in Anhui province (west of Shanghai), who had contact with poultry, became ill on 15 March 2013, and remains hospitalised in critical condition. There is no known epidemiological relationship among these three cases. A 38 yearold man in Hangzhou (Zhejiang province, south of Shanghai) became ill on 7 March 2013 and died on 27 March. All four cases presented with respiratory infections that progressed to severe pneumonia and breathing difficulties. On 31 March 2013, the Chinese Centre for Disease Control and Prevention announced the isolation in embryonated eggs of avian influenza viruses of the H7N9 subtype (designated A/Shanghai/1/2013, A/Shanghai/2/ 2013, and A/Anhui/1/2013) from the first three cases. The sequences of the coding regions of all eight viral genes were deposited in the influenza sequence database of the Global Initiative on Sharing All Influenza Data (GISAID) on 31 March (Table 1). On 5 April 2013, the Hangzhou Center for Disease Control and Prevention deposited the haemagglutinin (HA), neuraminidase (NA), and matrix (M) gene sequences of A/Hongzhou/1/2013 virus (Table 1), which was isolated in cell culture from samples obtained from the 38 yearold man. All four human influenza A(H7N9) viruses are similar at the nucleotide and amino acid levels, suggesting a common ancestor. The HA gene of the novel viruses belongs to the Eurasian lineage of avian influenza viruses and shares ca. 95% identity with the HA genes of low pathogenic avian influenza A(H7N3) viruses isolated in 2011 in Zhejiang province (south of Shanghai) (Figure 1, Table 2). The NA gene of the novel viruses is ca. 96% identical to the low pathogenic avian influenza A(H11N9) viruses isolated in 2010 in the Czech Republic.

来源出版物:Euro Surveill, 2013, 18(15): 7-21

被引频次:159

Infectivity, transmission, and pathology of human-isolated H7N9 influenza virus in ferrets and pigs

Zhu, H; Wang, D; Kelvin, DJ; et al.

Abstract: The emergence of the H7N9 influenza virus in humans in Eastern China has raised concerns that a new influenza pandemic could occur. Here, we used a ferret model to evaluate the infectivity and transmissibility of A/Shanghai/2/2013 (SH2), a human H7N9 virus isolate. This virus replicated in the upper and lower respiratory tracts of the ferrets and was shed at high titers for 6 to 7 days, with ferrets showing relatively mild clinical signs. SH2 was efficiently transmitted between ferrets via direct contact, but less efficiently by airborne exposure. Pigs were productively infected by SH2 and shed virus for 6 days but were unable to transmit the virus to naive pigs or ferrets. Under appropriate conditions, human-to-human transmission of the H7N9 virus may be possible.

来源出版物:Science, 2013, 341(6142): 183-186

Human infection with a novel avian-origin influenza A (H7N9) virus

Gao, RB; Cao, B; Hu, YW; et al.

Background: Infection of poultry with influenza A subtype H7 viruses occurs worldwide, but the introduction of this subtype to humans in Asia has not been observed previously. In March 2013, three urban residents of Shanghai or Anhui, China, presented with rapidly progressing lower respiratory tract infections and were found to be infected with a novel reassortant avian-origin influenza A (H7N9) virus. Methods: We obtained and analyzed clinical, epidemiologic, and virologic data from these patients. Respiratory specimens were tested for influenza and other respiratory viruses by means of real-time reverse-transcriptase-polymerasechain-reaction assays, viral culturing, and sequence analyses. Results: A novel reassortant avian-origin influenza A (H7N9) virus was isolated from respiratory specimens obtained from all three patients and was identified as H7N9. Sequencing analyses revealed that all the genes from these three viruses were of avian origin, with six internal genes from avian influenza A (H9N2) viruses. Substitution Q226L (H3 numbering) at the 210-loop in the hemagglutinin (HA) gene was found in the A/Anhui/1/2013 and A/Shanghai/2/2013 virus but not in the A/Shanghai/1/2013 virus. A T160A mutation was identified at the 150-loop in the HA gene of all three viruses. A deletion of five amino acids in the neuraminidase (NA) stalk region was found in all three viruses. All three patients presented with fever, cough, and dyspnea. Two of the patients had a history of recent exposure to poultry. Chest radiography revealed diffuse opacities and consolidation. Complications included acute respiratory distress syndrome and multiorgan failure. All three patients died. Conclusions: Novel reassortant H7N9 viruses were associated with severe and fatal respiratorydisease in three patients.