中国首例甲型H1N1流感二代病例的临床特征

目的了解2009年我国首例甲型H1N1流感二代病例的流行病学、临床、病原学检查特点及预后转归。方法对患者流行病学及临床资料进行回顾性分析,并采用实时荧光聚合酶链反应测定甲型H1N1流感病毒核酸。结果患者与甲型H1N1流感输入病例接触1天后发病。以发热、咽痛、咳嗽起病,白细胞及CD4＋T淋巴细胞计数降低,无肺炎等并发症。多级机构检测咽拭子甲型H1N1流感病毒核酸阳性确诊甲型H1N1流感。RT-PCR测序证实其病毒核苷酸序列与一代输入病例的一致,同源性为100%。经奥司他韦抗病毒及对症治疗痊愈出院。结论本病例的传染源明确,为我国首例报告的甲型H1N1流感二代确诊病例,其临床表现轻,病情恢复快。未发生院内感染,早隔离早诊断等防控措施有效。     

甲型H1N1流感患者外周血白细胞和淋巴细胞亚群变化分析

目的 探讨甲型H1N1流感患者白细胞和淋巴细胞亚群的变化特点,为甲型H1N1流感的诊断、治疗和预后判断提供实验室依据.方法 采用全血细胞分析和流式细胞分析法分别检测59例甲型H1N1流感患者急性期和恢复期的外周血白细胞及淋巴细胞亚群,与43名健康人和24例普通甲型流感患者比较.结果 甲型H1N1流感轻症患者白细胞总数在急性期显著下降,重症患者白细胞总数下降不显著,而中性粒细胞显著升高;与普通甲型流感相似,所有H1N1流感患者淋巴细胞总数、CD3、CD4、CD8百分比和绝对值在急性期大幅度下降,恢复期迅速回升;而重症患者NK和NKT细胞绝对值在急性期下降幅度超过20%.结论 甲型H1N1流感患者白细胞和淋巴细胞亚群变化与普通甲流相似;急性期NK、NKT细胞绝对值的大幅降低可以提示病情重症化倾向.     

深圳市某医院138例甲型H1N1流感病例临床分析

目的 探讨甲型H1N1流感患者的临床特点。方法 对138例甲型H1N1流感患者的临床资料进行分析。结果 138例患者中男性95例,女性43例,年龄最小2岁,最大45岁,以青少年为主,80%以上患者具有发热、咳嗽、咽痛等临床症状,绝大部分患者在3～5d内退热,有17.4%的患者WBC不同程度减少,99.3%的患者在一周内治愈。结论 目前甲型H1N1流感患者以青少年发病为主,绝大部分为轻症病例,临床表现温和,多休息、多饮水、服用中成药及对症治疗能取得满意的疗效,无需过于恐慌。     

基于郑州甲型H1N1流感疫情来评估相关诊断标准

目的 基于郑州市2009年5月至2010年1月甲型H1N1流感疫情来评估甲型H1N1流感诊断标准.方法 对疫情进行流行病学分析,使用卡方检验检测数据中所记录特征间的关联,通过Logistics回归、潜在类别分析分别评估了甲型H1N1流感病毒检测试剂盒三组探针和除其以外是否需额外的特征用于临床诊断.结果 流行病学分析表明平均世代时间为(3.59±1.41)d([2.01,7.26]),感染率为0.258±0.088 3,再生数为1.94([1.12,3.18]).统计模型结果表明,三组探针、性别、年龄、体温均与甲型H1N1流感相关并且加入性别等特征,预测结果有显著性的提高.结论 甲型H1N1流感诊断中,试剂盒三组探针和其他额外特征应一起作为标准来诊断甲型H1N1流感.     

402例甲型H1N1流感病例流行病学特征分析

目的了解深圳市福田区甲型H1N1流感病例的流行病学特征,为甲型H1N1流感预防控制提供科学依据。方法应用描述性流行病学方法分析402例甲型H1N1流感病例的流行病学特征,包括病例的年龄、性别、职业分布、地区分布等。结果 402例甲型H1N1流感病例男性占58.71%,女性占41.29%;90.55%的病例集中在0～30岁年龄段,11～20岁年龄段病例最多,占总病例数的41.79%;从职业构成看,所有病例中,绝大多数为学生,占总病例数的64.18%。结论学生是甲型H1N1流感的危险人群,应当注重学校等场所的甲型H1N1流感防控工作。     

奥司他韦对新型甲型H1N1流感轻症病例治疗效果的回顾性分析

目的 通过回顾性分析系统评价奥司他韦(达菲)对新型甲型H1N1流感轻症病例的临床治疗效果.方法 收集2009年5-8月国内三家传染病医院的308例甲型H1N1流感住院患者的临床资料,了解甲型H1N1流感的年龄分布特征及主要临床特征,之后剔除不符合要求的研究对象,将289例甲型H1N1流感轻症患者分为对照组和达菲组,了解两组病例在发热持续时间以及病毒持续时间的差异.结果 甲型H1N1流感患者的发病年龄主要集中在10～29岁.发热是甲型H1N1流感的最主要症状,以低、中度发热(＜39℃)为主,咽喉疼痛、咳嗽、头痛、流涕也是常见症状,但呕吐及腹泻患者比例较少,分别为1.3％和3.9％.最后对照组和达菲组在发病-病毒转阴时间和治疗-病毒转阴时间上的差异均无统计学意义(P =0.32,0.93).结论 甲型H1N1流感发病以青少年为主,多数患者病情较轻,预后良好.对于甲型H1N1流感轻症患者而言,达菲并不能有效缩短发热持续时间及病毒持续时间,流感病毒可以迅速被机体自身免疫系统清除,对轻症患者使用达菲抗病毒治疗并无临床意义.     

基于郑州甲型H1N1流感疫情来评估相关诊断标准

目的基于郑州市2009年5月至2010年1月甲型H1N1流感疫情来评估甲型H1N1流感诊断标准。方法对疫情进行流行病学分析,使用卡方检验检测数据中所记录特征间的关联,通过Logistics回归、潜在类别分析分别评估了甲型H1N1流感病毒检测试剂盒三组探针和除其以外是否需额外的特征用于临床诊断。结果流行病学分析表明平均世代时间为（3．59±1．41）d（[2．01,7．26]）,感染率为0．258±0．0883,再生数为1．94（[1．12,3．18]）。统计模型结果表明,三组探针、性别、年龄、体温均与甲型H1N1流感相关并且加入性别等特征,预测结果有显著性的提高。结论甲型H1N1流感诊断中,试剂盒三组探针和其他额外特征应一起作为标准来诊断甲型H1N1流感。     

T淋巴细胞在甲型H1N1流感病毒感染中的变化及意义

目的 研究甲型H1N1流行性感冒（流感）患者外周血T淋巴细胞及其激活亚群的变化.方法 用流式细胞仪检测144例甲型HlNl流感患者和41例健康体检者淋巴细胞亚群,对其中83例患者进一步分析治疗前后T淋巴细胞及其激活亚群（HLA-DR＋CD3＋、HLA-DR＋CD4＋和HLA-DR＋CD8＋细胞）.结果 ①与对照组相比,H1N1并发肺炎组和H1N1组淋巴细胞数明显低于对照组,H1N1并发肺炎组淋巴细胞数明显低于H1N1组;H1N1并发肺炎组T淋巴细胞百分比明显低于对照组（P〈0.05）.②治疗前后CD3、CD8细胞百分比和绝对数均差异有统计学意义,治疗前显著降低,CD4细胞数治疗前显著降低.③治疗前后T淋巴细胞激活亚群（HLA-DR＋CD3＋、HLA-DR＋CD4＋和HLA-DR＋CD8＋细胞）百分比差异有统计学意义,治疗前显著降低.结论 测定甲型H1N1流感患者外周血T淋巴细胞及其激活亚群的变化有助于评价甲型H1N1流感患者感染早期的细胞免疫状况,可以作为甲型H1N1流感早期诊断的辅助指标.     

2009甲型H1N1流感大流行期间北京儿童的流感监测

目的 了解2009年甲型H1N1流感大流行期间北京地区儿童中流感流行的情况.方法 采用WHO推荐的实时荧光定量RT-PCR和国家流感中心推荐的分型方法,对2009年甲型H1N1流感大流行期间因流感样症状来首都儿科研究所附属儿童医院就诊患儿的咽拭子标本进行流感病毒核酸检测.结果 2009年6月1日至2010年2月28日期间共检测了4363份咽拭子标本,其中623例为甲型H1N1阳性,阳性率为14.3%,657例为其他甲型流感病毒阳性(15.1%),所有甲型流感病毒的总阳性率为29.3%.623例中有23例为危重症病例(占阳性患者的3.7%),其中5例死亡.618例信息完整的甲型H1N1病例中,患儿年龄为14天～16岁,性别比例为男比女为1.3:1.1～3岁儿童占25.2%,3～6岁学龄前儿童和6～12岁学龄儿童所占比例相近,各约占30%.在监测期间,仅呈现了一个甲型H1N1的流行波.2009年11月达到最高峰,随后减弱,2010年2月快速下降至2.7%.对监测期间每周20～30份临床标本同时进行季节性流感的监测显示,季节性H3N2、甲型H1N1和乙型流感交替流行.呼吸道合胞病毒(RSV)在甲型H1N1流行趋势减缓后逐渐流行成为流行优势株.结论 2009年6月至2010年2月北京地区儿童中出现甲型H1N1的流行,主要累及学龄前和学龄儿童.季节性流感和RSV与甲型H1N1交替流行.     

T淋巴细胞在甲型H1N1流感病毒感染中的变化及意义

目的 研究甲型H1N1流行性感冒(流感)患者外周血T淋巴细胞及其激活亚群的变化.方法 用流式细胞仪检测144例甲型HlNl流感患者和41例健康体检者淋巴细胞亚群,对其中83例患者进一步分析治疗前后T淋巴细胞及其激活亚群(HLA-DR+CD3+、HLA-DR+CD4+和HLA-DR+CD8+细胞).结果 ①与对照组相比,H1N1并发肺炎组和H1N1组淋巴细胞数明显低于对照组,H1N1并发肺炎组淋巴细胞数明显低于H1N1组;H1N1并发肺炎组T淋巴细胞百分比明显低于对照组(P<0.05).②治疗前后CD3、CD8细胞百分比和绝对数均差异有统计学意义,治疗前显著降低,CD4细胞数治疗前显著降低.③治疗前后T淋巴细胞激活亚群(HLA-DR+CD3+、HLA-DR+CD4+和HLA-DR+CD8+细胞)百分比差异有统计学意义,治疗前显著降低.结论 测定甲型H1N1流感患者外周血T淋巴细胞及其激活亚群的变化有助于评价甲型H1N1流感患者感染早期的细胞免疫状况,可以作为甲型H1N1流感早期诊断的辅助指标.     

一起新型甲型H1N1流感疫情的临床和实验室特点

目的分析一起新型甲型H1N1流感疫情患者的临床和实验室特点。方法某部集体发病患者35例,均由核酸检测方法确诊;回顾调查患者的密切接触史、实验室检测结果、治疗和预后等。结果本次疫情收治的35人,密切接触平均1．7d出现临床症状,首发症状为发热占97．1％（34／35）,咽痛65．7％（23／35）,咳嗽51．4％（16／35）,肌肉酸痛31．4％（11／35）,头痛28．6％（10／35）。病毒核酸检测阴性的平均天数为4．5d,奥司他韦治疗,5d标准疗程,所有患者7d后痊愈出院。结论本次疫情为比较典型的新型甲型H1N1流感。     

Interim report on the A/H1N1 influenza virus pandemic in Marseille,France, April-November 2009

We report here the results of a 7-month survey of the influenza A/H1N1 pandemic in the Virology laboratory of the public hospitals of Marseille (April–November 2009). In total, 8 587 samples were analysed during this period, of which 1 974 (23%) were positive for the novel influenza variant. The analysis of results obtained using rapid influenza diagnostic tests (RIDTs) revealed a global sensitivity of 49.4% (vs. molecular qRT-PCR detection), strongly correlated with age groups (varying from 30% to 58% for patients >40 age and <10, respectively), indicating that RIDTs can be helpful in accelerating the management of suspected cases. Epidemiological analysis showed that the winter influenza wave began in October in Marseille (i.e. 2 to 3 months earlier than usual seasonal influenza outbreaks) and that the majority of autochthonous cases were observed in patients younger than 20 years old, with a low number of cases in patients over 60 years old. In November 2009, 22.2% (167/754) of patients with a laboratory diagnosis of influenza A/H1N1 infection were hospitalized, of which 9% (15/167) were admitted to an intensive care unit (ICU). Patients in the extreme age groups (>40 years old and <1) were significantly more often hospitalized than others, and 2.4% of hospitalized patients died. During the last 3 weeks of the period, the average number of bed-days attributable to H1N1sw-positive patients was 31.4, of which 5.9 were in ICUs.     

2009-2010年山西省流感／甲型H1N1流感的病原学监测分析

目的分析掌握山西省2009--2010年流感／甲型H1N1流感的流行特征,为预测和防控流感／甲型H1N1流感流行提供科学依据。方法对哨点医院和集体发热疫情进行监测采样,采用病毒核酸检测法和细胞培养法分离鉴定流感／甲型H1N1流感病毒,并对2009年5月至2010年4月山西省录入“中国流感监测信息系统”的流感样病例监测报告数据及其样本病原学监测数据进行统计分析。结果山西省全年均有流感病毒活动,2009年流行优势毒株为甲型H1N1流感病毒,流行最高峰在11月（阳性率为58．1％,甲型H1N1占88．1％）,主要导致59岁以下人群发病,其中5-24岁年龄组阳性率较高,进入2010年后乙型（Victoria系）流感病毒的活动有所增加,成为流行株。结论流感样病例监测和病原学监测,可以及时反映流感活动状况,对于掌握该省流感／甲型H1N1流感流行规律有着重要意义。     

Clinical Accuracy of a PLEX-ID Flu Device for Simultaneous Detection and Identification of Influenza Viruses A and B

Respiratory tract infections caused by influenza A and B viruses often present nonspecifically, and a rapid, high-throughput laboratory technique that can identify influenza viruses is clinically and epidemiologically desirable. The PLEX-ID Flu assay (Abbott Molecular Inc., Des Plaines, IL) incorporates multilocus PCR and electrospray ionization-mass spectrometry to detect and differentiate influenza A 2009 H1N1 (H1N1-p), seasonal H1N1 (H1N1-s), influenza A H3N2, and influenza B viruses in nasopharyngeal swab (NPS) specimens. The clinical performance characteristics of the PLEX-ID Flu assay in symptomatic patients were determined in this multicenter trial. A total of 2,617 prospectively and retrospectively collected NPS specimens from patients with influenza-like illness between February 2008 and 28 May 2010 were eligible for inclusion in the study. Each specimen was tested in parallel by the PLEX-ID Flu assay and by the Prodesse ProFLU+ assay (Prodesse Inc., Madison, WI), to detect influenza A and B viruses. Specimens testing positive for influenza A virus by ProFLU+ were subtyped as H1N1-p, H1N1-s, or H3N2 by using the ProFAST+ assay (Gen-Probe Prodesse Inc.). The reproducibility of the PLEX-ID Flu assay ranged from 98.3 to 100.0%, as determined by testing a nine-specimen panel at three clinical sites on each of 5 days. Positive percent agreements (PPAs) and negative percent agreements (NPAs) of the PLEX-ID Flu assay were 94.5% and 99.0% for influenza A virus and 96.0% and 99.9% for influenza B virus, respectively. For the influenza A virus subtyping characterization, the PLEX-ID Flu assay had PPAs and NPAs of 98.3% and 97.5% for H1N1-p, 88.6% and 100.0% for H1N1-s, and 98.0% and 99.9% for H3N2, respectively. The overall agreements between the PLEX-ID and Prodesse ProFLU+/ProFAST+ assays were 97.1 to 100.0%. Bidirectional Sanger sequencing analysis revealed that 87.5% of 96 discrepant results between the PLEX-ID Flu and ProFLU+/ProFAST+ assays were found upon influenza A virus detection and H1N1-p subtyping. The PLEX-ID Flu assay demonstrated a high level of accuracy for the simultaneous detection and identification of influenza A and B viruses in patient specimens, providing a new laboratory tool for the rapid diagnosis and management of influenza A and B virus infections.     

Singleplex real-time RT-PCR for detection of influenza A virus and simultaneous differentiation of A/H1N1v and evaluation of the RealStar influenza kit

BackgroundA novel influenza A virus, subtype A/H1N1v emerged in April 2009 and caused the first influenza pandemic of the 21st century. Reliable detection and differentiation from seasonal influenza viruses is mandatory for appropriate case management as well as public health.ObjectivesTo develop and technically validate a novel one-step real-time RT-PCR assay which can be used for influenza A virus screening and subtyping of A/H1N1v in a singleplex fashion. To assess the clinical performance of a novel commercial influenza RT-PCR kit based on the in-house version.Study designA real-time RT-PCR assay targeting the matrix gene of influenza A viruses was developed and validated using in vitro transcribed RNA derived from influenza A/H1N1v, A/H1N1 and A/H3N2 virus as well as plaque-quantified influenza A/H1N1v, A/H1N1 and A/H3N2 virus samples. After validation of the in-house version the commercial RealStar kit was used to assess the clinical performance and specificity on a panel of influenza viruses including A/H1N1v, A/H1N1, swine A/H1N1, A/H3N2, avian A/H5N1 as well as patient specimens.ResultsThe lower limit of detection of the in-house version was 2149, 1376 and 2994 RNA copies/ml for A/H1N1v, A/H1N1 and A/H3N2, respectively. The RealStar kit displayed 100% sensitivity and specificity and could reliably discriminate influenza A viruses from A/H1N1v. No cross reaction with swine A/H1N1 and A/H1N2 was observed with the RealStar A/H1N1v specific probe.ConclusionBoth assays demonstrated high sensitivity and specificity and might assist in the diagnosis of suspected influenza cases.     

Clinical evaluation of rapid point-of-care testing for detection of novel influenza A (H1N1) virus in a population-based study in Spain

Limited information exists on the performance of antigen-based rapid influenza diagnostic tests (RIDT) in diagnosing the novel influenza A pandemic (H1N1) 2009 virus. Large studies evaluating these tests in consecutive patients with a broad clinical spectrum of influenza-like illnesses are needed. We assessed the ClearView® Exact Influenza A & B test (Inverness Medical, Cologne, Germany) in comparison with real-time (r)RT-PCR for detection of the novel influenza A (H1N1) in a population-based prospective study of 1016 adults and children with suspected influenza in Spain. Three hundred and one (29.6%) patients had a positive sample with the rRT-PCR assay for influenza A and B viruses, with 297 (29.2%) confirmed cases of the novel influenza A pandemic (H1N1) 2009 virus. Fifty (16.8%) patients with confirmed A (H1N1) 2009 virus were admitted to hospital, with six of them to the intensive care unit. In comparison with rRT-PCR, the ClearView® Exact Influenza A & B test had a sensitivity of 19% (95% CI 14–23), a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 75% (95% CI 72–78). The sensitivity of the test remained low across all demographic and clinical strata. Although a positive RIDT performed well in predicting PCR-confirmed infection with pandemic H1N1 virus, the sensitivity was very low and a negative test result was a poor predictor of the absence of infection.     

Viral aetiology of influenza-like illness in Belgium during the influenza A(H1N1)2009 pandemic

The purpose of this investigation was to determine the proportion of influenza-like illness (ILI) attributable to specific viruses during the influenza A(H1N1)2009 pandemic and to describe the demographic and clinical characteristics of ILI due to respiratory viruses in Belgium. Nasopharyngeal swabs were collected from ILI patients by general practitioners (GPs) and paediatricians (PediSurv) and analysed for viruses. Of 139 samples collected from children <5 years of age by PediSurv, 86 were positive, including 28 influenza (20%), 27 respiratory syncytial virus (RSV) (19%), 21 rhinovirus (17%), 12 human metapneumovirus (hMPV) (9%) and ten parainfluenza virus (PIV) (7%). Of 810 samples received from GPs, 426 were influenza (53%). Of 312 influenza-negative samples, 41 were rhinovirus (13%), 13 RSV (4%), 11 PIV (4%) and three hMPV (1%). Influenza mostly affected the 6-15 years old age group. Other respiratory viruses were commonly detected in the youngest patients. Similar clinical symptoms were associated with different respiratory viruses. Influenza A(H1N1)2009 was the most detected virus in ILI patients during the 2009-2010 winter, suggesting a good correlation between ILI case definition and influenza diagnosis. However, in children under 5 years of age, other respiratory viruses such as RSV were frequently diagnosed. Furthermore, our findings do not suggest that the early occurrence of the influenza A(H1N1)2009 epidemic impacted the RSV epidemic in Belgium.