北京市1例人感染H9N2禽流感病例的流行病学调查与分析

目的 分析北京市人感染H7N9禽流感疫情强化监测中发现的1例人感染H9N2禽流感病例流行病学调查情况,为今后科学防控人感染H9N2禽流感疫情提供参考.方法 采用现场流行病学和实验室检测相结合的方法,收集病例流行病学资料,采集并检测病例、暴露环境和密切接触者等标本,分析流行病学特征和可能的感染来源.结果 病例发病第3日和第7日咽拭子标本检测均为H9N2禽流感病毒核酸阳性.病例发病前10天内无禽类接触史,但病例平时活动有暴露于H9N2禽流感病毒污染环境的可能.密切接触者在医学观察期内均未出现流感样症状.结论 该病例为北京市首例成人感染H9N2禽流感确诊病例,同时也是北京市第二例H9N2禽流感确诊病例.医疗机构加强流感样病例监测是及时发现人感染H9N2禽流感病例的重要手段.     

北京市首例人感染H9N2禽流感病例的流行病学调查

目的 分析2016年12月北京市朝阳区确诊的l例人感染H9N2禽流感病例流行病学特征.方法 访谈病例发病前后的相关知情人,调查病例发病经过和可能感染来源.采集病例、密切接触者及环境标本,应用实时荧光定量PCR(real-timePCR)方法,检测甲型流感病毒及H9N2禽流感病毒特异的核酸片段.对病例咽拭子标本和l件阳性环境标本中的H9N2禽流感病毒血凝素(Hemagglutinin,HA)基因进行序列测定和分析.结果 病例表现为轻症流感样病例症状,发病前15天曾有活禽市场暴露史.该市场环境标本中H9N2禽流感病毒阳性率为18.2％ (2/11).病例咽拭子标本与市场环境标本中病毒的HA基因高度同源,氨基酸相似度为100％,在进化关系上同属于欧亚系的Y280分支.4名密切接触者在医学观察期内未出现过发热、咳嗽等呼吸道症状.结论 病例感染来源与活禽市场环境暴露有关.加强流感监测以及活禽市场的管理对于防控人感染禽流感疫情具有重要意义.     

湖北省首例人感染H5N6禽流感病例流行病学调查

目的 对湖北省首例人感染H5N6禽流感病例的流行病学资料进行分析,探讨病例发现过程、调查处理措施、实验室检测方法,为防控人感染H5N6禽流感疫情提供依据.方法 采用描述性流行病学方法,分析湖北省首例人感染H5N6禽流感病例诊治过程、密切接触者信息,开展现场流行病学调查,并采集病例、密切接触者、活禽市场外环境标本进行实验室检测分析.结果 患者2016年4月9日发病,体温40℃,有活禽市场暴露史.发病早期采集的下呼吸道标本(痰液、气管分泌液)为H5N6禽流感病毒核酸阳性,而上呼吸道标本H5N6禽流感病毒核酸检测均为阴性.患者无外出史和H5N6禽流感病例接触史.患者经两个月的治疗痊愈出院.密切接触者58人均未出现发热和呼吸道感染症状.采集病例经常路过的两家活禽市场和一家土鸡专卖店外环境标本共36份,其中检出H5N6禽流感病毒核酸1 1份,阳性率为30.56％.结论 该病例为湖北省首例人感染H5N6禽流感病例,属本地感染的散发病例,未出现人传人.传播途径可能为:活禽市场通过禽-环境-人的途径传播.在病例诊断中,下呼吸道标本(尤其是痰液、气管分泌液)具有重要意义.另外,尽早应用奥司他韦对病例的成功救治起到了重要的作用.     

国家卫生和计划生育委员会印发《医院人感染H7N9禽流感病毒核酸检测标准操作程序》等技术规范

根据人感染H7N9禽流感疫情联防联控工作机制会议议定事项及《关于医院开展人感染H7N9禽流感病毒核酸检测有关工作的通知》（卫办医政函（2013）383号,以下简称《通知》）精神,为指导医院做好人感染H7N9禽流感病毒核酸检测工作,国家卫生和计划生育委员会组织制定了《医院人感染H7N9禽流感病毒核酸检测标准操作程序》,并委托中国疾控中心制定了《人感染H7N9禽流感病毒核酸检测实验室生物安全保障基本要求》等技术规范。现已下发供医院在开展人感染H7N9禽流感病毒核酸检测时参考使用。     

一例儿童轻型人感染H7N9禽流感确诊病例调查

目的 分析2013年北京市海淀区一例人感染H7N9禽流感病例的发病、诊治和感染来源情况,提出疫情控制措施.方法 采集患儿标本进行实验室检测,应用《人感染H7N9禽流感个案调查表》对患儿及其家属开展面对面问卷调查,获得现场资料.结果 患儿以上呼吸道症状为首发症状,经门诊治疗痊愈,传染源不明.患儿无肺部感染,未服用达菲,经过抗炎、抗病毒治疗.结论 人感染H7 N9禽流感是一种新出现的传染病,传染和流行特征未明,要加强流感样病例监测、流感病原学监测、不明原因肺炎监测等传染病监测工作,及时发现病例,及早采取防治措施.     

2011-2012年肇庆市禽流感职业暴露人群及外环境病毒分布监测分析

目的了解肇庆市禽类职业暴露人群禽流感病毒感染状况以及外环境禽流感病毒的分布情况。方法采集禽类职业暴露人员血清样本,用红细胞血凝抑制试验（HI）检测H5N1流感抗体;采集外环境样本,用荧光定量PCR法检测禽流感病毒FluA、H5、H7和H9核酸。结果2011-2012年共采集职业暴露人员血清样本400份,检测H5N1抗体均为阴性;共采集外环境有效样本202份,检出FluA阳性25份,阳性率为12．38％,其中AH9亚型阳性14份（56．00％）。AH7亚型阳性1份（4．00％）,A未分型10份（40．00％）,未检出AH5亚型。结论肇庆市职业暴露人群尚未发现感染高致病性禽流感H5N1病毒．夕h环境存在禽流感病毒的污染,H9亚型是主要的病原体。     

一例儿童轻型人感染H7N9禽流感确诊病例调查

目的 分析2013年北京市海淀区一例人感染H7N9禽流感病例的发病、诊治和感染来源情况,提出疫情控制措施调整意见.方法 采集患儿标本进行实验室检测,应用《人感染H7 N9禽流感个案调查表》与患儿及其家属面对面问卷调查,获得现场资料.结果 患儿以上呼吸道症状为首发症状,经门诊治疗痊愈,传染源不明.患儿无肺部感染,经过抗炎、抗病毒治疗,未服用达菲.结论 人感染H7 N9禽流感是一种新出现的传染病,传染和流行特征未明,要加强流感样病例监测、流感病原学监测、不明原因肺炎监测等传染病监测工作,及时发现病例,及早采取防治措施.     

基于iTRAQ技术的人感染H7N9禽流感病例血浆蛋白质组学特征分析

目的 分析人感染H7N9禽流感病例与正常人之间血浆蛋白质组学差异.方法 收集华北地区首例人感染H7N9禽流感病例发病期和恢复期血浆标本,以及同时期病例父亲(未感染病毒)血浆标本,分离提取血浆蛋白,通过同位素标记相对与绝对定量(isotopically labeled relative and absolute quantification,iTRAQ)技术联合液相色谱串联质谱(liquid chromatography tandem mass spectrometry,LC-MS/MS)技术对样本进行蛋白质质谱检测.利用PANTHER平台对差异蛋白质组进行Gene Ontology(GO)注释以及基因路径(pathway)分析.结果 本研究鉴定得到与人感染H7N9禽流感病毒感染相关的差异表达蛋白共250个,其中表达上调蛋白合计159个,表达下调蛋白合计91个.这些差异蛋白共参与了11个生物学过程、共参与了7个分子通路.结论 入感染H7N9禽流感病毒可能导致7个分子通路发生改变.     

人感染H7N9禽流感病毒的流行特征分析

目的分析人感染H7N9禽流感病毒的流行特征,并对人感染H7N9禽流感与外界环境导致发病之间的关联进一步了 解遥方法分析自然因素尧社会因素对人感染H7N9病毒流行特征的特点尧影响因素遥结果收集我科室68 例人感染H7N9禽流感 病毒病例,根据地区分布有3 例死亡曰根据年龄比较,逸60 岁的有45 例,臆60 岁的有23 例曰根据性别院男性38 例,女性30 例曰 根据职业院离退休人员有22 例,农民有26 例,其他职业有20 例曰根据接触禽类史情况院确定与禽类接触史的有14 例,剩余为不 确定是否有接触史的有54 例曰根据按月份院3 月21 例,4 月47 例曰比较发病至入院隔离时间院有33 例入院时间明确,当天入院 患者有11 例,最长在12 d后入院曰比较发病时间和检测时间院在进行H7N9检测中,有21 例是在4 d内,47 例在9 d内遥结论 人感染H7N9禽流感病毒的流行特征经过分析后,未能明确传染和流行特征遥因此,需要对疫情加强监测,对自然尧社会因素的 作用进行深入研究     

利用反向遗传学技术构建H5N9重组流感病毒株

目的 利用反向遗传学技术构建来源人感染禽流感病毒H5N1和H7N9 HA和NA基因的H5N9亚型禽流感病毒.方法 全基因合成A/Beijing/01/2003(H5N1)禽流感病毒HA基因片段和A/Zhejiang/DTID-ZJU10/2013(H7N9)禽流感病毒NA基因片段,插入到pHW2000载体,与携带有A/Puerto Rico/8/34(H1N1)的6个内部基因的pHW2000重组质粒一起转染293T和MDCK混合细胞,拯救H5N9重组病毒.结果 核酸测序、HA和NA基因转录和表达检测、细胞病变分析确定利用该反向遗传学系统可以成功拯救H5N9病毒.重组H5N9病毒在MDCK细胞上复制增殖能力低于相同方法拯救H1N1病毒.结论 利用反向遗传学技术成功构建一株H5N9重组病毒.     

2017~2018年成都市三区县外环境禽流感监测分析

目的 监测四川省成都市三区县外环境中禽类流行性感冒（禽流感）病毒的分布状况,为人禽流感防控提供参考依据。方法 我中心在2017年5月~2018年5月采用实时荧光定量PCR检测成都市三区县外环境中甲型流感通用病毒,再将阳性标本进行H5、H7、N9和H9分型,采用χ2检验比较定性资料。结果 在497份样本中,甲型流感病毒阳性标本87份,检出率为17.91%;分型实验中,H5、H7、N9和H9分别检出7份、6份、12份和41份,其阳性检出率依次为1.41%、1.21%、2.41%、8.25%,未分型成功23份,占总样本的4.63%。结论 成都市三区县外环境存在禽流感病毒污染,有人感染禽流感风险;需加强对外环境及高危人群禽流感监测,并规范对市场的管理机制,落实消毒和检疫准入等预防措施。     

A study of family clustering in two young girls with novel avian influenza A (H7N9) in Dongyang,Zhejiang Province,in 2014

BackgroundThe avian influenza A H7N9 virus, previously unknown in humans, has infected humans in many areas of China since February 2013. Here we report on a clustering case of H7N9 in two little girls in one family in Dongyang city, Jinhua area, Zhejiang Province.ObjectivesTo determine (1) whether the infections were due to person-to-person transmission or to co-exposure to poultry and (2) the prevalence of this novel H7N9 virus in Dongyang inferred by this family clustering case.Study designSamples were collected from patients and environment. We undertook detailed epidemiological investigations and laboratory work. Phylogenetic analyses were done based on the sequenced genomes. The concentration of cytokines and chemokines in the serum was detected by cytometric bead array analyses.ResultsA mixture of H7 and H9 was detected from the environmental sample. The three H7N9 viruses shared one infection source. The index patient who had significantly higher levels of IL-4, IL-8 and IL-10 suffered severe infection.ConclusionsBased on a comparison with previous isolations of the virus in 2013, H7N9 has evolved different lineages through recombination with local H9N2 viruses. Determining whether it was human-to-human transmission or exposure to the same live poultry, since both patients had identical exposure histories, was ambiguous. The results from the cytokine analyses agreed with the conclusion that H7N9 severity is associated with a higher level of cytokines/chemokines. Long term influenza surveillance remains essential to allow for early warning of potential transmission events.     

Effects of closing and reopening live poultry markets on the epidemic of human infection with avian influenza A virus

Live poultry markets (LPMs) are crucial places for human infection of influenza A (H7N9 virus). In Yangtze River Delta, LPMs were closed after the outbreak of human infection with avian influenza A (H7N9) virus, and then reopened when no case was found. Our purpose was to quantify the effect of LPMs’ operations in this region on the transmission of influenza A (H7N9) virus. We obtained information about dates of symptom onset and locations for all human influenza A (H7N9) cases reported from Shanghai, Jiangsu and Zhejiang provinces by May 31, 2014, and acquired dates of closures and reopening of LPMs from official media. A two-phase Bayesian model was fitted by Markov Chain Monte Carlo methods to process the spatial and temporal influence of human cases. A total of 235 cases of influenza A (H7N9) were confirmed in Shanghai, Jiangsu and Zhejiang by May 31, 2014. Using these data, our analysis showed that, after LPM closures, the influenza A (H7N9) outbreak disappeared within two weeks in Shanghai, one week in Jiangsu, and one week in Zhejiang, respectively. Local authorities reopened LPMs when there was no outbreak of influenza A (H7N9), which did not lead to reemergence of human influenza A (H7N9). LPM closures were effective in controlling the H7N9 outbreak. Reopening of LPM in summer did not increase the risk of human infection with H7N9. Our findings showed that LPMs should be closed immediately in areas where the H7N9 virus is confirmed in LPM. When there is no outbreak of H7N9 virus, LPMs can be reopened to satisfy the Chinese traditional culture of buying live poultry. In the long term, local authorities should take a cautious attitude in permanent LPM closure.     

Clinical and epidemiological survey and analysis of the first case of human infection with avian influenza A(H7N9) virus in Hangzhou, China

To investigate and report on the clinical and epidemiological characteristics of the first case of human infection with avian influenza A(H7N9) virus in Hangzhou, China. A field epidemiological survey was used to study the first case in Hangzhou. The patient was a 39-year-old male chef with a history of exposure to a farm product market and to poultry prior to the onset of disease on 15 March 2013. He had diarrhea, chills, pyrexia, and intermittent cough with freshly red foamy bloody sputum early in his disease. His fever > 39 °C continued for a week with rapid progression. Computed tomography findings showed extensive bilateral consolidation, followed by multiorgan failure. The patient died on the morning of 27 March. His infection was eventually confirmed 1 week later on 3 April. Flu-like symptoms including fever and cough were found in 46 of his 138 close contacts. This was the first case of human infection with avian influenza A(H7N9) virus in Hangzhou. None of the close contacts had onset of the disease. The case patient’s condition progressed rapidly. The source of infection might be his exposure to the farm product market, but the mode of exposure remains unclear.     

Coinfection of avian influenza virus (H9N2 subtype) with infectious bronchitis live vaccine

Avian influenza virus of H9N2 subtype is pathotyped as a non-highly pathogenic virus. However, frequent incidences of avian influenza of high mortality that are caused by H9N2 viruses have been observed in broiler chicken farms in Iran and some other Asian countries. Coinfections or environmental factors may be involved in such cases. Infectious microorganisms have been implicating in taking part in the cases of coinfection. We studied the effect of experimental coinfection of H9N2 avian influenza virus with infectious bronchitis live vaccine, which is used extensively in chicken farms in Iran. Clinical signs, gross lesions, viral shedding and mortality rate of the experimentally infected birds were examined. Coinfection of infectious bronchitis live vaccine and H9N2 avian influenza virus led to an extension of the shedding period of H9N2 virus, increasing the severity of clinical signs and mortality rates, causing macroscopic lesions in the embryos.     

中国职业暴露人群感染H6N6禽流感病毒血清学调查

目的 系统评估我国职业暴露人群感染H6N6禽流感病毒的状况.方法 本研究利用我国2009-2011年开展的高致病性H5N1禽流感病毒职业暴露人群血清学监测所采集的近15 000份血清标本,开展H6N6禽流感病毒血清学调查.结果 本研究中检测到H6N6禽流感病毒阳性血清共10份,分别来自不同的职业暴露人群,包括活禽市场、家禽规模养殖场、家禽散养户、屠宰加工场和野生候鸟栖息地.从地域上看该10份阳性血清来自8个不同的省份,分布在我国的南北方.结论 这是我国大陆地区首次报道人感染H6亚型禽流感病毒.