上海地区人群甲型H1N1流感抗体水平监测分析

Objective To understand levels of antibody to swine-origin influenza A(H1 N1) virus (A/ H1N1) among different age groups in Shanghai, and to compare the levels between antibodies to A/H1N1 and to 2008-2009 seasonal influenza vaccine virus A/Brisbane/59/2007(H1N1). Methods The anti-A/HlN1 antibody levels were determined among 5 age groups (0-5 months, 6 months-4 years, 5-24 years, 25-59 years, and ≥60 years) with routine micro-hemagglutination inhibition test. The positive rates of the antibodies among different age groups were compared by Pearson's X2 test and Fisher' s exact probability test. Results The positive rate of antibody to A/H1N1 in the whole population in Shanghai was 9.2% (37/404). The highest rate was 25.0% (21/84) in the age group of ≥60 years, the next was 10. 0% (8/80) in the age group of 25-59 years, the positive rates in other groups were lower. The result of Pearson's X2 test showed that there were statistically significant differences in the positive rates of the antibodies among different age groups. Of 329 sera positive for antibody to 2008 -2009 seasonal influenza vaccine virus A/Brisbane/59/ 2007 (H1N1), 31 had anti-A/HlNl antibodies, and of 75 sera negative for antibody to A/Brisbane/59/ 2007(H1N1), 6 had anti-A/HlNl antibodies. The result of Pearson's X2 test showed that there were no significant differences in positive rates of antibody to A/H1N1 between the two types of population. Conclusions The anti-A/HlNl levels in Shanghai population are low, and people are generally susceptible to A/H1N1. The sera positive for antibody to A/Brisbane/59/2007(H1N1) can not provide cross-protection against A/H1N1.     

2009年上海地区甲型流行性感冒流行及甲型H1N1病毒分离株变异分析

目的 了解2009年上海地区人群流行性感冒(流感)的流行特征和流行期间甲型H1N1分离株基因和抗原的变异.方法 采集2009年上海地区哨点医院和学校聚集性流感样患者咽拭子标本,接种犬肾细胞(MDCK细胞)分离流感病毒,直接荧光免疫法鉴定流感病毒型,RT-PCR法鉴定亚型,对部分甲型H1N1流感病毒进行血凝素(HA)、神经氨酸酶(NA)等片段全基因测序,分析甲型H1N1流感病毒HA、NA等基因变异.结果 2009年上海地区冬春季人群流感中,季节性H1N1和H3N2流感同时存在,进入第32周时,甲型H1N1和季节性H3N2流感同时流行,第40周后主要是甲型H1N1流行.甲型H1N1流行株HA进化分析显示,不同区域、不同月份分离株互有穿插,上海地区分离株聚集成簇形成一个分枝,与西班牙、俄罗斯、丹麦等国的流行株接近.HA演绎推导氨基酸位点虽有变异,但都不位于抗原决定区域;NA基因演绎推导氨基酸位点未观察到274位点及与耐奥司他韦药物相关其他位点的变异;PB2蛋白氨基酸序列分析显示,第627位和第701位氨基酸分别是谷氨酸和天冬氨酸,为禽源流感病毒PB2蛋白氨基酸位点.结论 2009年上海地区冬春季人群流感,季节性H1N1和H3N2同时流行,夏秋季开始甲型H1N1、季节性H3N2在人群中同时流行,之后以甲型H1N1为主.甲型H1N1与早期分离株比较有一定变异,但尚未出现流行病学意义的抗原漂移株,仍表现为对人的高亲和力和低致病性特征.     

犬肾传代细胞分离流行性感冒病毒致细胞病变的敏感性

目的 了解犬肾传代细胞系(MDCK)细胞对甲型流行性感冒(流感)患者鼻咽拭标本培养1代、2代、3代致细胞病变的敏感性.方法 甲型流感患者鼻咽拭标本在MDCK细胞盲传3代培养,倒置显微镜观察每代细胞致细胞病变效应产生情况.结果 经胶体金快速检测为甲型流感的279份流感样患者鼻咽拭标本,MDCK培养第1代产生致细胞病变为184份,占65.9%,第2代产生致细胞病变为255份,占91.4%,第3代产生致细胞病变为269份,占96.4%.279份标本的细胞培养液经多重RT-PCR检测鉴定为甲型流感病毒的有271份.结论 MDCK分离培养甲型流感患者鼻咽拭标本经盲传3代后,基本可达到95%以上的阳性分离率.     

实时细胞动态监测的流感病毒株耐药性研究

目的:了解实时细胞动态监测(RTCA)系统,由细胞病变导致金电极板电阻抗变化的研究;评价磷酸奥司他韦对上海地区不同亚型流感流行株体外抗病毒效果。方法:随机选取2009年-2010年上海地区流感不同亚型流行株,采用实时细胞动态监测(RTCA)系统和传统倒置显微镜观察细胞CPE方法,检测磷酸奥司他韦的抗病毒效果。结果:实时细胞动态监测(RTCA)系统通过病变细胞引起电极板的电阻抗变化的观察,结果连续、实时、客观、可信;磷酸奥司他韦对研究中选取的14株上海地区不同亚型流感流行株有抑制病毒感染细胞的效果。结论:实时细胞动态监测系统比较于传统观察CPE方法,获取的实验信息实时、客观、敏感,但是实验费用昂贵。磷酸奥司他韦(达菲)对上海地区不同亚型流感病毒具有较好的体外抗病毒效果。     

上海地区人群甲型H1N1流感抗体水平监测分析

Objective To understand levels of antibody to swine-origin influenza A(H1 N1) virus (A/ H1N1) among different age groups in Shanghai, and to compare the levels between antibodies to A/H1N1 and to 2008-2009 seasonal influenza vaccine virus A/Brisbane/59/2007(H1N1). Methods The anti-A/HlN1 antibody levels were determined among 5 age groups (0-5 months, 6 months-4 years, 5-24 years, 25-59 years, and ≥60 years) with routine micro-hemagglutination inhibition test. The positive rates of the antibodies among different age groups were compared by Pearson's X2 test and Fisher' s exact probability test. Results The positive rate of antibody to A/H1N1 in the whole population in Shanghai was 9.2% (37/404). The highest rate was 25.0% (21/84) in the age group of ≥60 years, the next was 10. 0% (8/80) in the age group of 25-59 years, the positive rates in other groups were lower. The result of Pearson's X2 test showed that there were statistically significant differences in the positive rates of the antibodies among different age groups. Of 329 sera positive for antibody to 2008 -2009 seasonal influenza vaccine virus A/Brisbane/59/ 2007 (H1N1), 31 had anti-A/HlNl antibodies, and of 75 sera negative for antibody to A/Brisbane/59/ 2007(H1N1), 6 had anti-A/HlNl antibodies. The result of Pearson's X2 test showed that there were no significant differences in positive rates of antibody to A/H1N1 between the two types of population. Conclusions The anti-A/HlNl levels in Shanghai population are low, and people are generally susceptible to A/H1N1. The sera positive for antibody to A/Brisbane/59/2007(H1N1) can not provide cross-protection against A/H1N1.     

上海地区在校中学生接种甲型H1N1流感疫苗前后抗体水平监测分析

 目的  了解上海地区在校中学生接种甲型H1N1流感疫苗前后的抗体水平;观察甲型H1N1流感疫苗对该人群的免疫保护作用。 方法    应用常规微量血凝抑制试验（micro-hemagglutination inhibition test, HIT）对上海地区在校中学生分3个时间段进行甲型H1N1流感病毒抗体的血清学监测,3个时间段的抗体阳性率比较采用Pearson χ2 检验进行分析。 结果  2009年甲型H1N1流感流行前上海地区在校中学生的血清抗体阳性率仅为1.3%。经过一段时间流行后,血清抗体阳性率升至8.5%。接种甲型H1N1流感疫苗后,血清抗体阳性率升至87.3%。经Pearson χ² 检验分析,3个时间段在校中学生的血清甲型H1N1流感抗体阳性率差异有统计学意义（χ²=243.7,P<0.05）。 结论  在甲型H1N1流感流行前,上海地区在校中学生对其几乎没有免疫力,接种甲型H1N1流感疫苗能为该人群提供较好的免疫保护作用。     

2009年上海地区甲型流行性感冒流行及甲型H1N1病毒分离株变异分析

目的 了解2009年上海地区人群流行性感冒(流感)的流行特征和流行期间甲型H1N1分离株基因和抗原的变异.方法 采集2009年上海地区哨点医院和学校聚集性流感样患者咽拭子标本,接种犬肾细胞(MDCK细胞)分离流感病毒,直接荧光免疫法鉴定流感病毒型,RT-PCR法鉴定亚型,对部分甲型H1N1流感病毒进行血凝素(HA)、神经氨酸酶(NA)等片段全基因测序,分析甲型H1N1流感病毒HA、NA等基因变异.结果 2009年上海地区冬春季人群流感中,季节性H1N1和H3N2流感同时存在,进入第32周时,甲型H1N1和季节性H3N2流感同时流行,第40周后主要是甲型H1N1流行.甲型H1N1流行株HA进化分析显示,不同区域、不同月份分离株互有穿插,上海地区分离株聚集成簇形成一个分枝,与西班牙、俄罗斯、丹麦等国的流行株接近.HA演绎推导氨基酸位点虽有变异,但都不位于抗原决定区域;NA基因演绎推导氨基酸位点未观察到274位点及与耐奥司他韦药物相关其他位点的变异;PB2蛋白氨基酸序列分析显示,第627位和第701位氨基酸分别是谷氨酸和天冬氨酸,为禽源流感病毒PB2蛋白氨基酸位点.结论 2009年上海地区冬春季人群流感,季节性H1N1和H3N2同时流行,夏秋季开始甲型H1N1、季节性H3N2在人群中同时流行,之后以甲型H1N1为主.甲型H1N1与早期分离株比较有一定变异,但尚未出现流行病学意义的抗原漂移株,仍表现为对人的高亲和力和低致病性特征.     

人感染猪流行性感冒病毒的病原特征和分子进化

2009年4月,在美国加利福尼亚州的2例流行性感冒(流感)样疾病患者的鼻拭子标本中检测出一种新型甲型H1N1病毒[1],该毒株被确认为是引起之前墨西哥持续几周的呼吸道疾病暴发疫情的首要病原体,随后该新型流感病毒通过快速的人际传播,陆续席卷全球.     

人感染猪流行性感冒病毒的病原特征和分子进化

2009年4月,在美国加利福尼亚州的2例流行性感冒(流感)样疾病患者的鼻拭子标本中检测出一种新型甲型H1N1病毒[1],该毒株被确认为是引起之前墨西哥持续几周的呼吸道疾病暴发疫情的首要病原体,随后该新型流感病毒通过快速的人际传播,陆续席卷全球.