卢龙县一起人杯状病毒引起急性胃肠炎暴发的流行病学调查

目的调查河北省卢龙县急性胃肠炎暴发的流行情况，分析发病原因。方法应用流行病学调查方法对卢龙县发生一起暴发性急性胃肠炎进行调查，采用ELISA和RT-PCR方法进行人杯状病毒检测，并对PCR产物克隆测序，进行遗传进化分析。结果在调查的736人中，发病134例，罹患率为18．20％，1例死亡。发病年龄范围在1-77岁，以青壮年发病较多。6月25～30日为发病高峰。6份粪便标本中，ELISA方法检出3份杯状病毒阳性，RT-PCR方法确认1例，并鉴定为诺如病毒GI/2基因型。结论证实由杯状病毒引起急性胃肠炎暴发。     

兰州地区5岁以下婴幼儿病毒性腹泻的分子流行病学研究

目的调查兰州地区5岁以下婴幼儿病毒性腹泻的流行情况,了解四种主要腹泻病毒在儿童中的分布情况。方法采集2009年7月至2010年6月兰州大学第一医院儿科5岁以下腹泻患儿粪便标本290份及儿童保健中心健康婴幼儿正常粪便标本114份,采用酶联免疫吸附试验（ELISA）检测轮状病毒抗原,采用巢式聚合酶链反应对轮状病毒阳性标本进行分型;采用反转录．聚合酶链反应（RT—PCR）检测杯状病毒和星状病毒,聚合酶链反应（PCR）检测腺病毒。结果290份腹泻标本中四种病毒的阳性率分别为：轮状病毒39．31％,杯状病毒11．38％,腺病毒10．69％,星状病毒4．83％;对114份轮状病毒阳性标本G、P分型,G3型及P[8]型为优势株;114份正常标本轮状病毒检出率为0,杯状病毒检出7例,星状病毒检出1例,腺病毒检出5例。结论病毒性病原在兰州地区婴幼儿腹泻中占有重要地位,长期系统的监测具有重要意义。     

荧光定量RT-PCR在流感病毒检测上的应用

目的　探讨实时荧光定量RT PCR检测方法在流行性感冒检测诊断上的意义。方法　收集集体暴发疑似流感、SARS患者的咽拭子标本 16起 2 0 7份和双份血清标本 10 4份 ,应用荧光定量RT PCR检测方法、MDCK细胞培养法和血凝抑制试验进行病原学和血清学检测。结果　 2 0 7份集体暴发疑似流感、SARS患者的咽拭子标本中用荧光定量RT PCR检测 ,阳性 79份。阳性率 38 16 % (79 2 0 7)。MDCK细胞培养 ,16起中有 13起共 14 5份咽拭子有 6 2份标本阳性。阳性率 2 9 95 % (6 2 2 0 7)。两者的阳性率差异有显著意义 (χ2 =8.6 4 ,P <0 0 0 5 )。有 9起 10 4份成功的采集了双份血清 ,经HI试验有 6 4份双份血清与H3N2亚型抗原产生血抑 4倍增长 ,阳性率 6 1 5 4 % (6 4 10 4 )。结论　荧光定量RT PCR方法检测流感病毒能够在 3～ 4h内得出结果、且操作方便、特异性强、灵敏度高。因此我们认为实时荧光定量RT PCR方法 ,可作为一种快速的流感病毒检测诊断方法。     

南京地区婴幼儿杯状病毒感染的分子流行病学研究

目的了解南京地区婴幼儿杯状病毒腹泻的感染状况、临床表现以及分子流行病学特征。方法采集2010年7月至2011年6月南京医科大学附属南京儿童医院5岁以下腹泻患儿粪便标本及儿童保健中心健康婴幼儿粪便标本各428份。采用反转录-聚合酶链反应（RT—PCR）检测杯状病毒,测序确定其基因型别。结果428份腹泻样本中有63份为杯状病毒阳性,检出率为14．72％。其中诺如病毒GⅡ型58例,未检出诺如病毒GI型,札如病毒5例,以诺如病毒GⅡ-42006b型为主要流行株。428份健康对照组标本杯状病毒检出19例,诺如病毒6例,札如病毒11例,2例为诺如病毒GⅡ型和札如病毒混合感染。结论南京地区婴幼儿中存在不同基因型杯状病毒感染,流行毒株以GⅡ-2006b为主。     

长春地区2010年度婴幼儿腹泻的病原学研究及流行病学特点

目的 了解长春地区四种主要腹泻病毒病原构成及流行病学特点.方法 收集长春市儿童医院5岁以下住院患儿腹泻样本共460例,轮状病毒采用ELISA试剂盒检测,杯状病毒、星状病毒采用逆转录-聚合酶链反应( RT-PCR)法,腺病毒采用聚合酶链反应(PCR)法进行鉴定.结果 460份标本中轮状病毒占35.22％( 162/460);杯状病毒占20.43％( 94/460),星状病毒占9.78％(45/460),腺病毒占3.70％(17/460),混合感染达7.17％(33/460),发病患儿以2岁以下婴幼儿为主.对162份轮状病毒阳性标本进行G/P分型,结果示G1P[8]为主要流行株,杯状病毒以GⅡ-4亚型为主要流行株,星状病毒为Ⅰ型,腺病毒为Ad41.结论 长春地区婴幼儿病毒性腹泻的病原中轮状病毒是最主要病原,其次为杯状病毒、星状病毒和腺病毒.     

太原市5岁以下腹泻住院儿童的病毒病原及其流行特征

目的 了解山西省太原市5岁以下腹泻住院儿童四种主要腹泻病毒的流行情况.方法 收集山西儿童医院2007年10月至2008年11月5岁以下全部住院腹泻患儿的粪便标本,采用ELISA试剂盒来检测轮状病毒;采用聚合酶链反应（PCR）检测腺病毒;逆转录-聚合酶链反应（RT-PCR）法检测星状病毒和杯状病毒并对轮状病毒进行分型.结果 346份标本中轮状病毒占40.8%、杯状病毒占7.5%、星状病毒占6.4%、腺病毒占3.2%.对141份轮状病毒阳性标本进行G1P分型,G1型是最优势株,P型优势株为P[8].四种病毒主要是感染2岁以下婴幼儿,RV有明显的季节的特征,9-11月份（48.92%）为发病高峰.结论 轮状病毒为最主要的病毒病原,G1P[8]型为主要流行株,秋冬季为发病高峰,2岁以下为发病高危人群,混合感染多见.     

2006-2015年成都地区5岁以下病毒性腹泻住院患儿病原学特征分析CSCD

目的 对成都地区5岁以下急性腹泻病患儿进行病毒学监测,了解引起腹泻常见病毒的流行特征,为指导病毒性腹泻的防控提供科学依据.方法 采集成都市妇女儿童中心医院儿童消化科2006年3月至2015年6月5岁以下腹泻住院患儿粪便标本,并送四川省疾病预防控制中心进行病毒RNA提取与检测,并记录患儿临床资料.采用ELISA、RT-PCR方法对轮状病毒抗原进行检测与分型;采用RT-PCR方法对杯状病毒、星状病毒、腺病毒进行检测与分型.结果 共收集1-59月龄腹泻住院患儿粪便标本份共2 331份（男1 446份,女885份）,阳性检出率58.0％,以7-12月龄为好发年龄.轮状病毒阳性检出率28.3％,11 -12月份为流行季节.杯状病毒阳性检出率23.3％,9月份为流行季节,诺如病毒GII为主要感染株,未发现暴发流行.星状病毒阳性检出率1.5％,主要于1-3月份检出.腺病毒阳性检出率5.1％,主要于5-8月份检出,2011年有过小流行.2007年以后,轮状病毒的检出率较前明显下降,而同时杯状病毒检出率逐年升高,2010-2015年杯状病毒成为引起5岁以下患儿腹泻的主要病毒之一.绝大多数病毒性腹泻患儿为急性病程（91.2％）,以轻度脱水为主,其次为中度脱水,无重度脱水.可伴消化道外表现,轮状病毒的消化道外表现较杯状病毒多见,但在随访中均恢复正常.结论 病毒性腹泻是5岁以下儿童急性腹泻病常见原因,成都地区以轮状病毒、杯状病毒为主要病原体.     

南京地区婴幼儿杯状病毒感染的分子流行病学研究

目的 了解南京地区婴幼儿杯状病毒腹泻的感染状况、临床表现以及分子流行病学特征.方法 采集2010年7月至2011年6月南京医科大学附属南京儿童医院5岁以下腹泻患儿粪便标本及儿童保健中心健康婴幼儿粪便标本各428份.采用反转录-聚合酶链反应( RT-PCR)检测杯状病毒,测序确定其基因型别.结果 428份腹泻样本中有63份为杯状病毒阳性,检出率为14.72％.其中诺如病毒GⅡ型58例,未检出诺如病毒GⅠ型,札如病毒5例,以诺如病毒GⅡ-4 2006b型为主要流行株.428份健康对照组标本杯状病毒检出19例,诺如病毒6例,札如病毒11例,2例为诺如病毒GⅡ型和札如病毒混合感染.结论 南京地区婴幼儿中存在不同基因型杯状病毒感染,流行毒株以GⅡ.2006b为主.     

长春地区2010年度婴幼儿腹泻的病原学研究及流行病学特点

目的了解长春地区四种主要腹泻病毒病原构成及流行病学特点。方法收集长春市儿童医院5岁以下住院患儿腹泻样本共460例,轮状病毒采用ELISA试剂盒检测,杯状病毒、星状病毒采用逆转录一聚合酶链反应（RT-PCR）法,腺病毒采用聚合酶链反应（PCR）法进行鉴定。结果460份标本中轮状病毒占35．22％（162／460）;杯状病毒占20．43％（94／460）,星状病毒占9．78％（45／460）,腺病毒占3．70％（17／460）,混合感染达7．17％（33／460）,发病患儿以2岁以下婴幼儿为主。对162份轮状病毒阳性标本进行G／P分型,结果示G1P[8]为主要流行株,杯状病毒以GII-4亚型为主要流行株,星状病毒为I型,腺病毒为Ad41。结论长春地区婴幼儿病毒性腹泻的病原中轮状病毒是最主要病原,其次为杯状病毒、星状病毒和腺病毒。     

一起由水污染引起的儿童及成人A组轮状病毒腹泻暴发

目的 确定2006年11月广西大新县大范围腹泻暴发性流行的病原及其分子生物学特点.方法进行流行病学个案调查和粪便标本的实验室检测,用ELISA试剂盒进行A组轮状病毒的检测,对检测阳性标本进行轮状病毒分型并对其中4份检测阳性轮状病毒的vfy7全基因扩增.结果 采集的64份腹泻患者粪便标本中共有30份检测为轮状病毒阳性,总阳性率为46.9%,此次暴发的流行病学和临床特征也符合轮状病毒腹泻特征,RT-PCR进行G/P分型显示为G1P[8]型轮状病毒,VP7氨基酸显示第68位氨基酸改变.结论 G1P[8]型A组轮状病毒是此次腹泻暴发的病原.值得注意的是,此次A组轮状病毒暴发累及儿童和成人.     

Laboratory investigation of enteroaggregative Escherichia coli O untypeable:H10 associated with a massive outbreak of gastrointestinal illness.

A massive outbreak of gastrointestinal illness occurred in Tajimi city, Gifu prefecture, in June of 1993 in which 2,697 children in elementary and junior high schools developed severe diarrhea. Stool specimens from 30 children with severe protracted diarrhea were studied. Twenty-seven strains of enteroaggregative Escherichia coli (EAggEC) isolated from 12 of 30 patients all belonged to the same serotype, O untypeable (OUT):H10, and showed the same biochemical characteristics and antibiotic susceptibility pattern. These strains were negative for the virulence factors of the four standard categories of diarrheagenic E. coli (enterotoxigenic, enteropathogenic, enteroinvasive, and enterohemorrhagic). However, the isolates showed an aggregative pattern of adherence to HEp-2 cells and had a 60-MDa plasmid and an astA gene, which encodes heat-stable enterotoxin-1 production. These data suggested that the EAggEC serotype OUT:H10 was associated with this massive outbreak of gastrointestinal illness.     

一起水源性诺如病毒感染性腹泻爆发的调查

目的了解一起社区感染性腹泻爆发的特点和流行原因,探讨爆发疫情调查处理的经验并为制定防治对策提供科学依据。方法采用现场流行病学调查分析和实验室检测方法。结果2月11日至18日,该社区发生感染性腹泻病例173例,罹患率为2.40%,病例最小1岁,最大89岁,男女性别比为1.25∶1,发病最多的为40～49岁组,所有病例均为居住或工作在该社区的人员,工厂、居家均有病例出现,居家病例呈一定的家庭聚集性,病例的临床表现基本相同,以腹泻、腹痛、恶心、呕吐和发热等症状为主,大部分症状较轻,病程1～3 d。从病人粪便标本中检测到诺如病毒抗原,采取改善饮用水、隔离治疗病人和健康教育等综合措施后,疫情迅速得到控制。结论本次疫情为一起诺如病毒感染性腹泻爆发,爆发原因可能是该社区水厂供水系统被污染。社区小水厂卫生安全存在诸多薄弱环节,建议完善水厂卫生管理制度,落实水质消毒措施,尽快改用市政自来水供水。     

Clinical characteristics and laboratory assay of adult Japanese encephalitis patients in an outbreak in Yuncheng, Shanxi Province, 2006]

OBJECTIVE: To study the clinical and laboratory characteristics of adult Japanese encephalitis (JE) patients in a JE outbreak in Yuncheng, Shanxi Province in 2006. METHOD: All the clinical data from the Second People's Hospital in Yuncheng city were analyzed, part of patients' sera and cerebrospinal fluid were tested by serology and RT-PCR. RESULTS: The majority of patients were middle-aged and elderly, 77.8% (35/45) of the total cases were more than 40 years old. Severe and fulminating type cases accounted for 60.0% (27/45). Most patients had underlying diseases. IgM antibody to JE virus (JEV) in serum was positive in each of the 45 patients analyzed and 4-fold or greater rise in sera neutralization antibody titer were found in convalescent serum. JEV nucleic acid was positive in part of cerebrospinal fluid specimens. CONCLUSION: Viral encephalitis emerged in Yuncheng city, Shanxi Province was Japanese encephalitis B, and most of the cases belonged to elderly group.     

Prevalence and genetic diversity of human caliciviruses (HuCVs) in Mexican children

Human caliciviruses (HuCVs) contain two genera: "Norwalk-like viruses" (NLVs) and "Sapporo-like viruses" (SLVs). The importance of the two genera as a cause of acute gastroenteritis of infants and children remains unknown. Beginning in 1989, a birth cohort of children in Mexico was enrolled and monitored for acute gastroenteritis. A subset of 115 diarrhea stool specimens from 76 children and 66 non-diarrhea stool specimens from 64 children was examined for HuCVs by RT-PCR by using a primer pair (p289/290) that detects both NLVs and SLVs. Twenty-two (19%) of the 115 diarrhea stool specimens and 5 (7%) of 66 non-diarrhea stool specimens produced RT-PCR products of expected size (319 bp for NLVs and 331 bp for SLVs). Twenty of the twenty-seven strains were cloned and sequenced. Pairwise sequence analysis showed that 9 (60%) and 6 (40%) of the 15 strains from the diarrhea stools were NLVs and SLVs, respectively. The same proportions of NLVs (60%) and SLVs (40%) were observed in the non-diarrhea stools. Strains in the NLV genus could be further divided into four clusters: Lordsdale, MxV, and HV and one potentially new cluster. Strains in the SLV genus could be divided into three clusters: Sapporo/82, Lon/92, and a potentially new cluster. Strains from the Lordsdale cluster were the most common among these children. The findings of both genera and multiple clusters of HuCVs co-circulating and the identification of new strains of HuCVs in the population justify the need for future studies of HuCVs in infants and children.     

Probabilities in norovirus outbreak diagnosis.

BACKGROUND: Noroviruses are recognized as the most common cause of outbreaks of acute gastroenteritis. Yet, diagnostic testing for norovirus is based mostly on RNA detection by RT-PCR, which is not widely available. While antigen detection tests (ELISAs) are easier to perform, they are in general less sensitive. OBJECTIVES: Our aim was to provide a scientific basis for declaring norovirus as the causative agent of an outbreak of acute gastroenteritis. STUDY DESIGN: Statistical analysis used binomial distribution to determine the minimal number of positive samples, and the probability of detecting the required number of positive samples, for different tests, required to assign norovirus as the causative agent of an outbreak of acute gastroenteritis. RESULTS: For either a standard RT-PCR or a commercially available ELISA, finding only 1 sample positive out of 2, 3 or 4 samples is sufficient to assign norovirus as the causative agent of an outbreak of acute gastroenteritis. However, when ELISA is used, the probability of detecting this required minimum number of positive samples is low when small numbers of samples are tested (57% when 2 samples are tested; 72% when 3 samples are tested). In order to reach a 90% probability of detecting a norovirus outbreak (false negativity at outbreak level <10%), at least 3 samples should be tested using RT-PCR, and 6 samples when using an ELISA. CONCLUSIONS: The sensitivity for NoV outbreak diagnosis will increase from 57% to 92%, or from 84% to 96%, for ELISA or RT-PCR respectively, when sample size increases from 2 to 6. Thus, using ELISA instead of RT-PCR for the detection of norovirus in stool samples will result in considerable numbers of false negative outbreaks unless a minimum of 6 samples are tested per outbreak.