A群脑膜炎奈瑟氏菌脂多糖抗原血清学分型的流行病学意义

从江西等省收集了A群脑膜炎奈瑟氏菌324株,应用我们所报道的分型方法可以将96.91%的菌株分成三个主要的脂多糖血清型。不同地区所收集的A群菌株脂多糖血清型的地区分布是不同的,病人与其密切接触者的菌株具有相同的脂多糖血清型,L₁₀型菌株的致病力较强,可以引起流脑流行。本文所述的分型方法操作简便,分型率高。因此,作者认为A群菌株脂多糖血清学分型具有一定的流行病学意义,此分型方法很适于流行病学调查。     

我国沿海副溶血性弧菌血清型分布的实验调查

对135株来自我国沿海海产鱼贝类、海水、海泥及食物中毒患者的副溶血性弧菌,进行了血清学分型实验。结果表明:属于已知OK抗原型的106株(78.5%),分布于O1~12群的29个血清型。另有10株菌(7.4%)的血清型属于8个已知K抗原与其它O群组合的新菌型(神奈川现象阴性)。从群别看,以O₄群最多(38/30.4),O₁群次之(26/20.8);从型别看,以O₁K₃₂最多(18/14.4),O₅K₁₇次之(10/8.0)。O₁~O₅群菌株为108株80%)。仅具有O群抗原而未检出K抗原的有19株(14.1%)。不同样品的菌型分布未发现有特殊差异。     

河南省A群脑膜炎双球菌脂多糖血清型及其流行病学意义的初探

本文应用血凝仰制(HAI)方法将我省从1976～1985年所收集的94株A群脑膜炎奈瑟氏菌(NM)进行了脂多糖(LPS)分型,可以分成L_9L_(10)和L_(11)三个血清型,它们各占18.09％,67.02％和8.51％,总的分型率为93.61％。在62株病人菌株和32株带菌菌株中(多半来自于病人密切接触者)均以L_(10)型占优势,所以与病人菌株型比较一致,因此该种分型有助於追溯流脑传染源。从1976—1985年,我省一直可以检出L_1型菌株,而且占优势,这说明今后应监测该型菌在我省流脑流行中的作用。     

多位点酶电泳法(ET)用于我国A群脑膜炎奈氏菌的分型及流行病学意义

应用多位点酶电泳(ET)分型法从我国183株A群脑膜炎奈氏菌中分出24个ET型,其中ET₃、ET₁₃为70年代以来在我国引起流脑流行的优势型别。在不同的流行期中优势型别不相同。每一次流行只和一个ET优势型别有关。在流行间歇期,存在许多地方性的ET型别的菌株引起的发病和健康带菌者。     

甲1型流感病毒的抗原漂移

本研究对1977~1983年期间分离的新甲₁型部分毒株之间。新甲₁型毒株和老甲₁型部分毒株之间,进行了抗原性状的分析,结果表明,1983年新甲,型出现了血凝素抗原性状明显漂移的新变种株,其神经氨酸酶抗原虽有变异,但仍与近几年来流行的优势株相近,对此类毒株扩大流行的可能性进行了推测。对新老甲₁型毒株间抗原分析的结果表明,流感病毒的抗原漂移无一定方向。在新甲₁型变种中,不断出现老甲₁型所没有的新抗原成分。这种趋向表明,甲₁型流感可能不会在短期内自行消失。     

杭州地区沙门氏菌菌型分布调查

本文报告1977~81年杭州地区523株沙门氏菌菌型鉴定结果，它分属13个群或亚群，计有31个血清型（包括6个变种）。主要为B群占41.49%，其次为E群占31.36%，C群占22.56%，其余各群占4.59%。其中A~F群占99.04%，A~F以外群有4个；G₁、I、L、Q占0.96%。G₁群浦那沙门氏菌1977年尚属国内首次发现，I群非丁伏斯沙门氏菌国内亦属少见。主要流行菌株为德尔卑沙门氏菌，占21.8%，其次为鸭沙门氏菌，占15.87%，波茨坦沙门氏菌占11.28%，火鸡沙门氏菌占8.99%，鼠伤寒沙门氏菌占7.07%，其它如斯坦利、纽波特、阿贡纳、汤卜逊等沙门氏菌所占比例较小。
猪体带沙门氏菌以德尔卑为主，占42.5%，其次是鸭沙门氏菌，占32.5%，与人体感染情况一致，说明两者有密切关系。     

舟山群岛海产品和外环境副溶血性弧菌带菌调查及血清学分型

本文报道了1986~1987年对1003份海产品和外环境标本副溶血性弧菌带菌及血清型分布的调査结果。各类海产品普遍带菌,带菌率40~100%。检出率和气温有密切关系。外环境标本均有检出。对608株菌血清学分型结果,除O9群外,余12个群均有检出,主要菌群有O2、O5、O1、O4、O3和O12等6个群,共检出103个血清型,最主要的菌型有O1K₃₂、O5K₁₇;O5K₁₅、O2K₂₈、O12K₃和O12K₅₂⁵¹等6个型。有17.9%的菌株不能分型.     

人流感与猪流感关系的监测

作者于1982年4月和1983年5月在成都地区采集了336份人血清和607份猪血清。以Hsw₁N₁、H₁N₁、H₂N₂、H₃N₂和B流感病毒为抗原，用血抑试验检测其抗体，血抑阳性猪血清用单扩溶血试验复核结果表明，凡能感染人的流感病毒均能感染猪，猪血清和人血清中血抑抗体阳性率的增长呈平行关系。
此外，在22份猪血清中发现了B流感病毒的血抑抗体，阳性率为3.6%。经单扩溶血试验复核，其阳性率为72.7%。其中，4份猪血清与B病毒进行了中和试验，3份有中和B病毒的能力，猪血清中甲₂型血抑抗体阳性率为78.3%，几何平均滴度为42.5，经单扩溶血试验复核，其阳性率为48.7%。血清学方面的事实证明B型流感病毒能感染猪，甲₂型流感病毒近年来在猪群中曾广泛流行，並讨论了这些发现。     

国内所见侵袭性大肠杆菌血清型

本文报告1984~85年间,国内13个省市送检的侵袭性大肠杆菌(EIEC)的鉴定与血清学分型结果。受检的276株中,确定为EIEC的77株(27.9%)。其中能引起豚鼠角膜炎的有毒力菌株68株(88.3%),11.7%菌株在较短时间内丧失了毒力(EIEC,Inv^-)。77株EIEC分布于7个O抗原的8个血清型,其中O₂₈ac:H-占49.2%,O₁₆₄:H-为22.1%,O₁₂₄有二个侵袭性血清型H-和H₃₀,占11.7%。O₂₉:H-,O₁₁₂ac:H-,O₁₃₆:H-,O₁₅₂:H-也占有一定比例。
在本文中,作者提出了侵袭性大肠杆菌的诊断标准与侵袭性大肠杆菌毒力丧失株的概念以及鉴别特征,并作了详细的讨论。     

浙江省腹泻患者致泻性大肠埃希菌血清型分布及其鉴定效率的评价

目的 了解浙江省致泻性大肠埃希菌（DEC）血清型分布并探讨其血清学鉴定分类方法的鉴定效率。方法 对2009年7月至2013年6月浙江省腹泻症候群病原谱监测网络菌株库中的696株DEC菌株（通过毒力基因鉴定）开展血清学凝集试验,比较毒力基因和血清学鉴定分类的结果。结果 696株DEC中288株（41.4%）能明确O抗原型别,分属于35种O血清群。171株（24.6%）H血清凝集,分属于21种H型。肠集聚性大肠埃希菌（EAEC）、产肠毒素性大肠埃希菌（ETEC）、肠致病性大肠埃希菌（EPEC）和肠出血性大肠埃希菌（EHEC）凝集率分别为31.9%（130/408）、70.6%（127/180）、31.5%（29/92）和14.3%（2/14）,分属于30、18和15种O血清群,1株EHEC为O157∶H7。EAEC和EPEC血清群相对较多样化,而ETEC则相对集中,不同类型DEC可具有同一血清群/型。根据血清学结果可分类的75株DEC中,42株毒力基因和血清学分类结果一致,33株不一致。结论 浙江省DEC血清群/型种类多样,单纯采用血清学筛查可造成极大的漏检或误分,建议采用毒力基因鉴定分类。     

某三甲医院2014—2018年医院感染现患率调查

目的了解医院感染的实际情况及变化趋势,分析医院感染的危险因素。方法选取某三级甲等医院,采用横断面调查方法,2014—2018年每年调查一次,调查期为1日,调查对象为当日全部在院和出院患者,统计分析5年医院感染资料。结果共调查患者9 718例,医院感染现患率为4.55%,例次现患率为5.01%,五年医院感染现患率及例次现患率均呈逐年下降趋势,差异均有统计学意义(均P0.001)。医院感染部位以下呼吸道为主,193例次,占39.63%,其次分别为手术部位(75例次,15.40%)、泌尿道(65例次,13.35%)和上呼吸道(29例次,5.95%)。医院感染现患率最高的科室为血液科(15.73%),例次现患率最高的为重症监护病房(16.72%)。共检出医院感染病原体414株,其中革兰阴性菌258株,革兰阳性菌112株,真菌38株,其他病原体6株。最常见的病原体为铜绿假单胞菌(51株),其次为大肠埃希菌(49株)、鲍曼不动杆菌(43株)、金黄色葡萄球菌(43株)和肺炎克雷伯菌(42株)。结论医院感染现患率调查有助于了解医院感染发生情况,器械相关感染和手术部位感染是医院感染防控的重点。     

163例ECMO治疗患者医院感染情况及其危险因素

目的 了解接受体外膜肺氧合(ECMO)支持治疗患者术后相关医院感染情况及其危险因素.方法 回顾性收集某院2013年1月—2019年12月应用ECMO支持治疗患者的病历资料,统计、分析ECMO术后医院感染情况及其危险因素.结果 163例ECMO支持治疗患者中,39例发生ECMO术后医院感染,感染发病率为23.93％.以下...     

Paradoxical response to a novel influenza virus vaccine strain: the effect of prior immunization.

BACKGROUND: repeated influenza immunization does not appear to adversely affect the serum antibody response to new influenza strains. OBJECTIVE: to determine whether the immune response to a new influenza strain was inferior in persons previously vaccinated compared with persons not previously vaccinated. DESIGN: randomized, double-blind clinical trial. SETTING: university affiliated community teaching hospital. PATIENTS: 139 healthy adult men and women, mean age 38 years. INTERVENTION: subjects were vaccinated as part of another study. They received influenza vaccines containing influenza strains A/Texas/36/91 (H1N1), A/Nanchang/933/95 (H3N2) and B/Beijing/184/93. One group received a licensed influenza vaccine while the other group received a similar vaccine except the A/Nanchang strain had a diminished potency. MEASUREMENTS: serum hemagglutination inhibition (HAI) antibody titers were determined prior to vaccination and two weeks afterward. If patients had a low postvaccination titer, they were revaccinated and HAI titers were determined two weeks later. RESULTS: 68 adults received the licensed vaccine and 70 received the subpotent vaccine. The groups were similar with regards to baseline characteristics. Those previously vaccinated had significantly lower postvaccination HAI geometric mean titers (GMTs) for all three vaccine strains (A/Texas--127 vs. 359, p < 0.001, A/Nanchang--31 vs. 93, p < 0.001 and B/Beijing--140 vs. 205, p < 0.05). The percentage of subjects with a presumed protective HAI titer of > or =40 was significantly lower among the previously vaccinated groups only for the new influenza strain, A/Nanchang (55% vs. 80%, p < 0.05). For the other two vaccine strains, the percentage with an HAI titer > or =40 was greater than 90% for both groups. CONCLUSIONS: the decrease in serologic response to influenza vaccine among healthy, young adults who were previously vaccinated appears to be unique for this year's influenza vaccine. Further studies are required to determine the frequency and clinical significance of this phenomenon observed in younger healthy adults, and whether it is a general one. Based on its proven efficacy, influenza vaccine should continue to be given on an annual basis to high risk children and adults and to all those 65 years or older.     

A novel serological assay for influenza based on DiD fluorescence dequenching that is free from observer bias and potentially automatable – A proof of concept study

BackgroundSerum hemagglutination inhibition (HAI) and microneutralization (MN) antibodies are often used as a correlate of protection for influenza. However, these manual assays are labor-intensive and difficult to standardize due to variability in biologic reagents used and subjective interpretation of the results.MethodsSera with known HAI and MN titers were used to assess a novel test based on the inhibition of fluorescence ‘dequenching’. Whole influenza virions (A/California/07/2009 (H1N1), A/Hong Kong/4801/2014 (H3N2) and B/Brisbane/60/2008) labelled with 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindodicarbocyanine perchlorate (DiD) were exposed to serial dilutions of serum and mixed with turkey red blood cells followed by acidification of the media (pH 5.0–5.5). The H1N1 and B/Brisbane strains were high hemagglutinating while the H3N2 strain had low hemagglutinating activity. In some experiments, labelled virions were subjected to repetitive freeze-thaw cycles prior to use in the assay.ResultsIn the absence of detectable HAI/MN antibodies, there were consistent and substantial increases from baseline DiD fluorescence upon acidification. Sera with known high titer HAI/MN antibodies reduced or completely prevented DiD dequenching at low dilutions with progressive increases in fluorescence at higher dilutions, which permitted a reproducible assignment of an antibody ‘titer’ based on baseline and acidified DiD fluorescence values. The ‘titers’ measured by the DiD dequenching assay were highly correlated with HAI/MN results for the H1N1 and B strains (Spearman’s correlation coefficients (r_s) 0.874 to 0.946, p < 10⁻⁷ to 10⁻³⁵). Correlations with HAI/MN titres for the low-hemagglutinating H3N2 strain tested were lower but remained statistically significant (r_s 0.547–0.551, p < 0.004). Freeze-thawing of the DiD pre-stained virus stocks had no significant impact on the results of the assay.ConclusionsThe DiD dequenching assay may be a labour-saving and more objective alternative to the classic serologies. This novel assay could theoretically be standardized across laboratories using pre-stained virions and has the potential to be fully automated.     

Use of traditional serological methods and oral fluids to assess immunogenicity in children aged 2–16 years after successive annual vaccinations with LAIV

BackgroundThe UK introduced quadrivalent live attenuated influenza vaccine (qLAIV) for children in 2013/2014. The impact of annual vaccination on effectiveness and immunogenicity is being assessed.MethodA phase III/IV open-label study of the immunogenicity of annual vaccination with qLAIV (Fluenz™) was conducted over three consecutive years (2014/15–2016/17) in 254, 249 and 162 children respectively. Serum responses to vaccine components were measured by Haemagglutination Inhibition (HAI) and anti-A(H1N1)pdm09 Neuraminidase (NAI) assays, stratified according to previous receipt of AS03_B-adjuvanted A(H1N1)pdm09 pandemic vaccine in 2009/10. Antibody levels to the A(H1N1)pdm09 and H3N2 vaccine components in oral fluids (OF) were explored using an ELISA.FindingsMore paired pre- and post-vaccination oral fluids (96%) than paired sera (87%) were obtained. Geometric mean titre rises using HAI assays were limited, with maximum rises seen in year one for both influenza B strains when 39% and 43% of subjects seroconverted (95% confidence interval 33–46% and 36–50%, respectively) and year two for influenza H3N2, when 40% (33–46%) individuals seroconverted. Prior pandemic vaccine receipt resulted in higher pre- and post-vaccination A(H1N1)pdm09 HAI titres and lower pre-and post-vaccination NAI (N1 neuraminidase) titres in all three years. OF results were congruent with HAI results; assay specificity compared to HAI was 88.1 and 71.6 percent, and sensitivity was 86.4 and 74.8 percent respectively for A(H1N1)pdm09 and H3N2.ConclusionIn all three study years, vaccination with qLAIV resulted in poor antibody responses. However, OFs are an alternative specimen type that allows self sampling, can easily be obtained from children, and their analysis leads to similar conclusions as classic serology by HAI. Their suitability for seroprevalence studies should be investigated. We demonstrated a sustained effect from prior receipt of the AS03_B-adjuvanted A(H1N1)pdm09 vaccine, even after repeat vaccination with qLAIV indicating that early exposure to influenza antigens has a significant long lasting effect.     

某三级甲等医院神经外科不同类型手术医院感染情况

目的 了解某三甲医院神经外科不同类型手术医院感染发生情况,为神经外科手术相关医院感染监测与防控提供思路和依据。方法 回顾性调查2016年1月1日—2018年12月31日该三甲医院神经外科手术患者的手术相关感染信息。结果 共调查6 688例神经外科手术患者,医院感染发生率为8.22%,其中手术部位感染（SSI）发生率最高（5.40%）,其次是手术后肺炎（POP,1.91%）。不同类型手术后的医院感染、SSI、POP、其他部位感染、器官腔隙感染发生率的差异均有统计学意义（均P<0.05）,其中颅内肿瘤切除手术和颅内血管介入手术的医院感染（11.35%和8.46%）、器官腔隙感染（7.39%和4.01%）的发生率较高。不同颅内肿瘤切除术后医院感染、SSI、POP、器官腔隙感染发生率的差异均有统计学意义（均P<0.05）,其中神经上皮来源肿瘤和颅咽管瘤的医院感染（23.19%和20.79%）、器官腔隙感染（17.27%和12.87%）的发生率较高。脑脊液共分离病原菌74株,其中革兰阳性菌54株,革兰阴性菌19株,真菌1株。结论 神经外科不同类型手术医院感染发生率差异较大,在资源有限的情况下,医院感染监测工作可将重点放在医院感染发生率高的手术类型中。     

公交车爆燃事件群体烧/创伤患者医院感染发病率及危险因素

目的了解群体烧/创伤患者医院感染发生情况,并探讨其危险因素。方法对2014年5月12日某院收治的"公交车爆燃事件"共25例住院群体烧/创伤患者的医院感染情况进行监测分析。结果 25例烧/创伤患者,其中发生医院感染7例,10例次,医院感染发病率为28.00%,例次发病率为40.00%;感染部位以创面和下呼吸道为主,分别占60.00%和30.00%。7例医院感染患者共检出病原菌30株,其中革兰阴性(G-)菌16株(53.34%)、革兰阳性(G+)菌13株(43.33%)、真菌1株(3.33%)。烧伤总面积大、吸入性损伤程度高、动静脉插管、泌尿道插管、气管切开、使用呼吸机、外科手术均是烧/创伤患者医院感染的危险因素。结论群体烧/创伤患者医院感染发病率较高,应根据其危险因素制定相应的干预措施,减少医院感染的发生。     

Novel hemagglutinin nanoparticle influenza vaccine with Matrix-M™ adjuvant induces hemagglutination inhibition,neutralizing, and protective responses in ferrets against homologous and drifted A(H3N2) subtypes

Influenza viruses frequently acquire mutations undergoing antigenic drift necessitating annual evaluation of vaccine strains. Highly conserved epitopes have been identified in the hemagglutinin (HA) head and stem regions, however, current influenza vaccines induce only limited responses to these conserved sites. Here, we describe a novel seasonal recombinant HA nanoparticle influenza vaccine (NIV) formulated with a saponin-based adjuvant, Matrix-M™. NIV induced hemagglutination inhibition (HAI) and microneutralizing (MN) antibodies against a broad range of influenza A(H3N2) subtypes. In a comparison of NIV against standard-dose and high-dose inactivated influenza vaccines (IIV and IIV-HD, respectively) in ferrets NIV elicited HAI and MN responses exceeding those induced by IIV-HD against homologous A(H3N2) by 7 fold, A(H1N1) by 26 fold, and B strain viruses by 2 fold. NIV also induced MN responses against all historic A/H3N2 strains tested, spanning more than a decade of viral evolution from the 2000–2017 influenza seasons whereas IIV and IIV-HD induced HAI and MN responses were largely directed against the homologous A(H3N2), A(H1N1), and B virus strains. NIV induced superior protection compared to IIV and IIV-HD in ferrets challenged with a homologous or 10-year drifted influenza A(H3N2) strain. HAI positive and HAI negative neutralizing monoclonal antibodies derived from mice immunized with NIV were active against homologous and drifted influenza A(H3N2) strains. Taken together these observations suggest that NIV can induce responses to one or more highly conserved HA head and stem epitopes and result in highly neutralizing antibodies against both homologous and drift strains.     

浙江省1 998年H3N2流感流行的溯源研究

目的 对1998年浙江省的H3N2流感流行进行溯源研究.方法 采用RT-PCR扩增浙江省1998年3株H3N2流感流行代表株的全基因组序列,并与GenBank上1995-1998年世界其他地区H3N2流感流行株进行比较;同时,采用交叉血凝抑制实验,计算各毒株间的抗原比.结果 HA基因进化树表明,1998年浙江省H3N2优势流行株A/Zhejiang/11/98、A/Zhejiang/18/98与1995-1996年世界各地以及1997年我国大陆的H3N2流行株间存在显著差异,在进化树上虽与A/Sydney/5/97同属一簇,但和美国纽约以及中国香港1997年后期流行株更为接近.在HA1、NA和MP基因上,A/Zhejiang/18/98与香港1997年后期流行株同源性最高,而在PA、HA和NS基因上,与纽约流行株的遗传距离也小于A/Sydney/5/97.A/Zhejiang/18/98与香港或纽约株在HA1区仅存在1～3个位点的氨基酸残基不同,而与A/Sydney/5/97存在7个位点的氨基酸残基差异,其中3个位点于抗原决定簇区.各毒株间的交叉血凝抑制实验表明A/Zhejiang/18/98与A/Sydney/5/97的抗原比已达2.0,提示二者在抗原性上存在一定差异.此外,1997-1998年H3N2各地流感流行的起始时间序列,也显示了该次流感传播的可能途径.结论 浙江省1998年H3N2流感的流行很可能是由1997年底H3N2新型流感变异株经纽约和香港输入中国大陆所导致.