2010年云南省部分人群甲型H1N1流感抗体监测分析

目的 了解云南省普通人群甲型H1N1流感抗体水平,分析和预测其流行趋势,为预防和控制疫情提供依据.方法 2010年1-3月,对云南省不同年龄组部分人群开展了4次调查,用血凝抑制试验进行抗体检测.结果 云南省普通人群甲型H1N1流感抗体阳性率为28.300(452/1 600),3月的抗体阳性率和GMT高于1,2月.结论...     

黑龙江省甲型H1N1流感感染血清学调查分析

目的了解黑龙江省甲型H1N1流感病毒感染状况,为评估研判疫情发展趋势提供信息支持。方法应用常规微量血凝抑制实验,对2009年12月～2010年3月共4次采集的医院门诊的就诊患者血清1 624份进行甲型H1N1流感抗体水平检测。结果黑龙江省甲型H1N1流感抗体阳性率为20.01%(325/1 624),疫苗的有效率为52.11%(37/71),自然感染率仅为12.04%(288/1 553)。黑龙江省医院、哈尔滨市儿童医院、哈尔滨市血站三家医疗机构中儿童医院的抗体阳性率最高(27.07%);甲型H1N1流感病毒HI抗体阳性率在性别上无显著差异,但在年龄组上有显著差异,6～17岁年龄组抗体阳性率最高33.57%(94/280),0～5岁年龄组次之为26.91%,56岁以上年龄组抗体阳性率最低为3.21%。结论甲型H1N1流感已经在黑龙江省流行,但人群抗体阳性率仅为20.01%,远低于70%的保护水平,有可能还会出现暴发流行疫情,应进一步加强甲型H1N1流感疫苗接种,特别是56岁以上的老年人应重点防护。     

2010年四川省甲型H1N1流感血清学调查

目的了解四川省人群甲型H1N1流感病毒抗体水平,为及时科学评估疫情发展趋势和完善防控策略与措施提供依据。方法按照国家方案采集不同年龄组人群血清标本,用血凝抑制(HI)试验方法进行抗体检测,HI抗体滴度≥1∶40判为阳性。结果四川省甲型H1N1流感阳性率17.39%(663/3 812);不同地区阳性率差异无统计学意义;6～17岁组阳性率最高(20.52%);男女性阳性率差异无统计学意义;就诊人群阳性率高于献血人群和体检人群,差异有统计学意义。结论四川省人群甲型H1N1流感阳性率较低,,甲型H1N1流感在人群中的自然感染未形成有效免疫屏障,甲型H1N1流感疫苗接种仍有必要。     

2009年北京市门头沟区甲型H1N1流感抗体水平监测

<正>2009年4月,甲型H1N1流感在墨西哥和美国暴发[1],5月16日北京市出现第1例甲型H1N1流感确诊病例,6月底才出现第1起聚集性疫情,直到9月上旬还未出现重症和死亡病例。9月初北京市门头沟区出现输入性病例,10月学校的聚集性病例增多,防控     

山东省甲型H1N1流感隐性感染者抗体调查

[目的]了解在山东省流行性感冒流行季节,甲型H1N1流感病毒的隐性感染状况,分析我省甲型H1N1流感病毒疫情趋势。[方法]2009年12月在我省部分医院门诊检验室和自愿献血站分年龄组采集就诊者和献血者血清400份,采用血凝抑制试验(HI试验)检测甲型H1N1流感抗体,观察人群对甲型H1N1流感病毒的感染状况。[结果]调查400人特定人群,甲型H1N1流感抗体阳性者19人,其中2名抗体阳性者注射了甲型H1N1流感疫苗,隐性感染率为4.25%。18～55岁年龄组隐性感染率最高(9.00%),不同年龄组间隐性感染率的差异有统计学意义(P0.05),不同性别间的差异无统计学意义(P0.05),有无流感样症状者抗体阳性率高于无流感样症状者,差异有统计学意义(P0.05)。[结论]我省甲型H1N1流感在人群中隐性感染率较低,人群主动免疫力低下。     

2010年广东省某医院职工甲型H1N1流感血清抗体调查

目的 了解在甲型H1N1流感（甲流）流行季节里,医护人员的甲流血清抗体水平以及接种甲流疫苗的效果,为制定医护人员防控流感的策略提供依据.方法 随机选取广东省某医院医护人员体检时所采集的血清标本,按有无接种甲流疫苗分为疫苗组（61人,在抽血2周前完成疫苗接种）、非疫苗组（329人）,采用常规血凝抑制试验微量半加敏法（HI...     

西安市新城区2010年健康人群甲型H1N1流感抗体调查分析

目的了解西安市新城区健康人群甲型H1N1流行性感冒(简称流感)病毒感染状况,以及甲型H1N1流感病毒抗体水平,分析和预测甲型H1N1流感的流行趋势,为预防和控制疫情提供依据。方法应用血凝抑制试验对西安市新城区不同年龄组健康人群的血清进行甲型H1N1流感病毒抗体检测。结果注射甲型H1N1流感疫苗后的抗体阳性率高,可以达到62.2%,总人群的甲型H1N1流感病毒的抗体阳性率是30.5%。结论注射甲型H1N1流感疫苗有效,但是人群对该病毒免疫力不高。     

佛山市南海区甲型H1N1流感血清学调查分析

目的了解佛山市南海区人群甲型H1N1流感感染现状。方法按照广东省卫生厅方案采集不同年龄组人群血清标本,用血凝抑制(HI)试验方法进行抗体检测,HI抗体滴度≥1∶40判为阳性。结果南海区甲型H1N1流感阳性率30.42%(146/480),以第三次调查阳性率最高(43.13%),3次调查总体阳性率差异有统计学意义(χ2=20.10,p≤0.001);4～24岁组阳性率最高(46.15%);男女性阳性率差异无统计学意义;城镇人群感染率高于农村,差异有统计学意义(χ2=12.76,p=0.004)。结论南海区发生了甲型H1N1流感社区流行,人群有一定感染率,农村的学校、幼托机构是防控重点。     

四川省成都市甲型H1N1流感血清学调查结果分析

目的了解成都市人群甲型H1N1流感感染现状。方法按照国家方案采集不同年龄组人群血清标本,用血凝抑制(HI)试验方法进行抗体检测,HI抗体滴度≥1∶40判为阳性。结果成都市甲型H1N1流感阳性率8.85%(108/1221);13～17岁组阳性率最高(13.85%,P0.05);男女性阳性率差异无统计学意义;就诊人群阳性率低于一般人群,但差异无统计学意义。结论成都市发生了甲型H1N1流感社区流行,但在人群中的自然感染未形成有效免疫屏障,甲型H1N1流感疫苗接种仍有必要。     

内蒙古2009年甲型H1N1流感病原与血清学监测结果分析

目的:分析2009年内蒙古甲型H1N1流感流行特点和健康人群感染状况,为进一步应对流感大流行提供科学依据。方法:采用RT-PCR、Real-time PCR法进行核酸检测,阳性样本进行鸡胚病毒分离培养。人群血清采用血凝(HA)和血凝抑制(HI)试验进行人群抗体检测。结果:全区各网络实验室共检测标本7663份,核酸阳性1543份,阳性率为20.14%。其中季节性H1N1阳性68份,H3N2阳性158份,甲型H1N1阳性957份,B型阳性164份,甲型流感阳性但无法分亚型的192份,混合4份;对本实验室检出的阳性标本509份进一步进行病毒分离培养,结果获得阳性毒株162株,阳性分离率为31.83%。采用血凝(HA)和血凝抑制试验(HI)对分离毒株型别鉴定,结果甲型H1N1份155份,占阳性毒株的96.91%;HI方法检测人群标本472份,抗体阳性95份,阳性率20.13%。结论:内蒙古地区2009年7月以后流行的流感优势株为甲型H1N1流感病毒,高峰出现在10月、11月;人群血清抗体检测表明人群抗体阳性率普遍偏低,学生的抗体水平相对较高。     

江苏省2009年3岁以上自然人群新甲型H1N1流感血清流行病学调查

目的 了解江苏省2009年3岁以上自然人群新甲型H1N1流感抗体水平及流行趋势.方法 利用微量半加敏血凝抑制(HI)方法检测江苏省不同时间(2008年11月和2009年7、8、11月)人群新甲型H1N1流感抗体,比较不同时间、人群及地区的新甲型H1N1流感保护性抗体阳性率和抗体几何平均滴度(GMTs).结果 在新甲型H1N1流感输入江苏地区后第一个流行季节内,2009年7、8、11月人群HI保护性抗体阳性率依次为3.46%、7.59%和16.94%,表现出随时间推移而呈总体增长趋势(P=0.000),不同时间点的性别间保护性抗体阳性率的差异无统计学意义(P＞0.05);除2009年11月外,不同性别间的抗体GMT差异均无统计学意义.同一时间点不同年龄组间、同一年龄组的不同时间点间,HI保护性抗体阳性率、抗体GMT水平比较的差异均有统计学意义(P＜0.05).HI保护性抗体阳性率和抗体GMT存在地区差异(P＜0.05).结论 在2009年8月后江苏地区12～17岁人群成为新甲型H1N1流感暴发的主要人群,至2009年11月该人群总体新甲型H1N1流感保护性抗体阳性率仍较低,该病在全省的流行仍将持续一段时间.     

职业暴露人群A(H5N1)和甲型H1N1流感血清抗体分析

目的:了解人禽流感A(H5N1)和甲型H1N1流感职业暴露人群中的感染状况。方法:对职业暴露人群进行个案调查,采用血凝抑制法(HI)检测职业暴露人群血清中人禽流感A(H5N1)和甲型H1N1流感抗体。结果:2009年-2010年采集的624份职业暴露人群血清中未检测出人禽流感A(H5N1)抗体,而在2009年采集的血清中有5份检测出甲型H1N1流感抗体,抗体阳性率为1.55%,2010年采集的血清中抗体阳性率为11.96%,其中<29岁阳性率为17.19%,30岁～59岁阳性率为10.87%。结论:职业暴露人群中未检测出A(H5N1)流感抗体,但仍需加强职业暴露人群监测。同时甲型H1N1流感抗体水平较低,缺乏相应的抗体水平保护。     

Serologic survey of pandemic influenza A (H1N1 2009) in Beijing, China

Objective

To examine the frequency and distribution of antibodies against pandemic influenza A (H1N1 2009) [H1N1] in populations in Beijing and elucidate influencing factors.

Methods

In January 2010, a randomized serologic survey of pandemic influenza A (H1N1 2009) was carried out. Six districts that were randomly selected with a total of 4601 participants involved in the survey have their antibody level tested by hemagglutination inhibition assay.

Results

Among the 4601 participants, the overall seropositive rate for pandemic influenza A (H1N1 2009) antibodies was 31.7%. The seropositivity prevalence in participants who received the pandemic H1N1 vaccination was 60.9%. Only 53.1% of the pandemic influenza A (H1N1 2009) seropositive individuals who had not received the vaccination experienced respiratory tract infection symptoms. Multivariate logistic regression revealed that factors such as age, occupation, dwelling type, whether the participant's family included students in school, and the vaccination history with pandemic influenza A (H1N1 2009) were associated with antibody titers (p < 0.05).

Conclusions

Our data indicated that almost 30.0% of the residents had appropriate antibody titers against pandemic influenza A (H1N1 2009) in Beijing, and these titers may provide an immune barrier.     

Lessons from pandemic influenza A(H1N1): the research-based vaccine industry's perspective

As A(H1N1) influenza enters the post-pandemic phase, health authorities around the world are reviewing the response to the pandemic. To ensure this process enhances future preparations, it is essential that perspectives are included from all relevant stakeholders, including vaccine manufacturers. This paper outlines the contribution of R&D-based influenza vaccine producers to the pandemic response, and explores lessons that can be learned to improve future preparedness.The emergence of 2009 A(H1N1) influenza led to unprecedented collaboration between global health authorities, scientists and manufacturers, resulting in the most comprehensive pandemic response ever undertaken, with a number of vaccines approved for use three months after the pandemic declaration. This response was only possible because of the extensive preparations undertaken during the last decade.During this period, manufacturers greatly increased influenza vaccine production capacity, and estimates suggest a further doubling of capacity by 2014. Producers also introduced cell-culture technology, while adjuvant and whole virion technologies significantly reduced pandemic vaccine antigen content. This substantially increased pandemic vaccine production capacity, which in July 2009 WHO estimated reached 4.9 billion doses per annum. Manufacturers also worked with health authorities to establish risk management plans for robust vaccine surveillance during the pandemic. Individual producers pledged significant donations of vaccine doses and tiered-pricing approaches for developing country supply.Based on the pandemic experience, a number of improvements would strengthen future preparedness. Technical improvements to rapidly select optimal vaccine viruses, and processes to speed up vaccine standardization, could accelerate and extend vaccine availability. Establishing vaccine supply agreements beforehand would avoid the need for complex discussions during a period of intense time pressure.Enhancing international regulatory co-operation and mutual recognition of approvals could accelerate vaccine supply, while maintaining safety standards. Strengthening communications with the public and healthcare workers using new approaches and new channels could help improve vaccine uptake. Finally, increasing seasonal vaccine coverage will be particularly important to extend and sustain pandemic vaccine production capacity.     

海南省甲型H1N1流感血清流行病学调查

目的了解海南省2009年甲型H1N1流感大流行高峰后期人群感染水平及流行趋势。方法于2009年12月和2010年1-3月共5次在海口市抽取医院门诊患者、血液中心志愿者,利用血凝抑制(HI)方法进行血清标本甲型H1N1流感抗体检测。结果 5次调查的人群抗体阳性率依次为10.50%(40/381)、16.06%(62/386)、31.35%(121/386)、23.16%(91/393)和38.02%(146/384),随时间推移总体呈增长趋势(χ2=81.17,P<0.05);除0～5岁组外,6～17岁、18～55岁及≥56岁组抗体阳性率均随时间推移而上升(χ2=4.22,P>0.05;χ2=21.25,P<0.05;χ2=39.05,P<0.05;χ2=26.85,P<0.05);6～17岁组抗体阳性率5次调查均最高。结论海南省甲型H1N1流感人群免疫水平逐步提高,该疾病在海南省的流行将维持在较低水平;6～17岁人群为主要感染人群。     

甲型H1N1流感大流行前后沈阳地区流感病原学流行特征

目的分析甲型H1N1流行性感冒(流感)大流行前后沈阳流感病原学流行特征。方法采集2005年10月—2011年3月连续5.5 a哨点医院的流感样病例咽拭子,进行流感病毒的分离和分型鉴定,并按甲型H1N1流感流行前后划分为3个时期。结果 3个时期共采集流感样病例咽拭子样本6 808份,分离到流感病毒861株,总分离率为12.6%;流行前、流行中和流行后3个时期流感病毒检出率分别为13.8%、18.2%和5.2%。男性和女性流感病毒感染率差异无统计学意义,不同时期流感样病例的年龄构成差异有统计学意义。新的甲型H1N1流感侵袭的人群主要是低年龄组人群,新的甲型H1N1流行期间和流行后,流感季节高峰发生前移。不同年度流感流行毒株型别不同,前1年监测周期的优势株在下1个周期中可被其他型别抑制甚至取代。结论甲型H1N1流感流行后沈阳的流感流行特征已发生了部分改变,这种改变是否持续存在还有待持续监测来得以验证,在2011—2012年监测周期中应密切关注A3(H3N2)亚型和新的甲型H1N1亚型流感毒株的活动情况。     

Immune response of single dose vaccination against 2009 pandemic influenza A (H1N1) in the Taiwanese elderly

We conducted a multi-center, randomized and laboratory-blinded clinical trial with subgroup analyses, involving adults aged greater than 60 years old (range 61–86 years old), to investigate the immunogenicity and the potential factors affecting the immune response of a monovalent, unadjuvanted, inactivated, split-virus vaccine. A total of 107 subjects were randomized to receive 15 and 30 μg of hemagglutinin antigen in a 1:1 ratio. The immunogenicity was detected through hemagglutination inhibition (HAI) test of serum obtained before and 3 weeks after vaccination. By 3 weeks after vaccination, HAI titer ≧1:40 was observed in 75.5% and 81.1% of participants receiving 15 and 30 μg of hemagglutinin antigen, respectively. Positive seroconversion was observed in 71.7% and 81.1% of recipients of the 15 and the 30 μg, respectively. The GMTs increased by a factor of 10.7 and 17.4 in the groups of 15 and 30 μg, respectively. This study indicated that one dose of 15 μg hemagglutinin antigen without adjuvant induced protective immune response in the majority of elderly. Multivariate logistic regression analyses showed that gender, age and diabetes were statistically significant factors affecting the seroprotection rate (p = 0.04, 0.01 and 0.01, respectively) and seroconversion rate (p = 0.01, 0.01 and 0.01, respectively).     

Serologic status for pandemic (H1N1) 2009 virus, Taiwan

We studied preexisting immunity to pandemic (H1N1) 2009 virus in persons in Taiwan. A total of 18 (36%) of 50 elderly adults in Taiwan born before 1935 had protective antibodies against currently circulating pandemic (H1N1) 2009 virus. Seasonal influenza vaccines induced antibodies that did not protect against pandemic (H1N1) 2009 virus.     

甲型H1N1流感病毒神经氨酸酶基因进化分析

目的 探讨2009年山东省甲型H1N1流感病毒神经氨酸酶(neuram inidase,NA)基因的进化及NA基因编码蛋白抗原性、酶活性位点、糖基化位点变异情况.方法 对山东省分离的20株甲型H1N1流感病毒的NA基因序列,用MEGA 4.0软件进行基因进化分析和氨基酸序列分析.结果 山东省2009年9月-2010年1月分离的20株甲型H1N1流感病毒NA基因的同源性均>99.2%,其中有4株的同源性为100%;与疫苗株[A-California-07-2009(H1N1)]、国内推荐株[A-Sichuan-SWL1-2009(H1N1)]的同源性分别为99.1%~99.5%和99.1%~99.6%;有13个神经氨酸酶基因的氨基酸发生了替换,为21、23、25、42、43、60、76、94、106、122、248、307和351位;未发生神经氨酸酶蛋白275位H-Y的替换.结论 山东省分离的甲型H1N1流感病毒NA基因高度保守,潜在抗原位点氨基酸分布相同;所有毒株的酶活性中心位点以及糖基化位点均高度保守;所有测定样本均未发生对达菲类药物的耐药性突变.     

Improved neutralizing antibody response in the second season after a single dose of pandemic (H1N1) 2009 influenza vaccine in HIV-1-positive adults

Neutralizing antibody titers were determined before and after a single dose of pandemic (H1N1) 2009 influenza vaccine in HIV-1-positive Japanese adults in the first season of the pandemic and in those in the second season who had already received the vaccine in the first season. The antibody response rate at 2-month post-vaccination increased significantly from 49.0% (50/102, 95%CI: 39.0-59.1%) in the 2009/2010 season to 66.7% (42/63, 95%CI: 53.7-78.1%) in the 2010/2011 season. Geometric mean antibody titers (fold dilution) at baseline, at 2 months, and at 4 months also increased significantly from 4.4 (95%CI: 3.3-5.7), 19.0 (95%CI: 13.4-26.8) and 13.7 (95%CI: 9.3-20.2), respectively, in the 2009/2010 season to 8.3 (95%CI: 5.8-11.7), 47.0 (95%CI: 32.2-68.6) and 38.2 (95%CI: 23.8-61.4), respectively, in the 2010/2011 season. Although the vaccine response was low in the first season, it was improved in the second season.