【作者】 杨学梅；

【导师】 金玉； 方肇寅； 段招军；

【作者基本信息】 兰州大学 ， 儿内科学， 2007， 硕士

【摘要】 研究背景：腹泻病是世界范围内尤其是发展中国家儿童发病和死亡的主要原因。每年全球约有150-200万儿童死于与腹泻相关的疾病或是并发症。轮状病毒、杯状病毒、腺病毒和星状病毒被认为是引起腹泻的主要病原，轮状病毒是世界范围内引起儿童重症腹泻的最常见病原，全球每年约44-60万儿童因轮状病毒腹泻而死亡，疫苗是唯一可行的预防和控制轮状病毒较高发病率和死亡率的方法，不同地区不同年份优势流行株有较大变异，有必要进行长期而系统的监测，为有效的疫苗研制和应用提供依据。目的：了解兰州地区主要的四种腹泻病毒的流行病学特点，为病毒性腹泻的防治提供依据。方法：收集兰州大学第一医院儿科2005年7月至2006年6月5岁以下住院腹泻患儿257例的粪便标本，采用Dako公司酶免疫试剂盒检测轮状病毒，对轮状病毒酶免疫法(ELISA)阳性标本，采用逆转录-聚合酶联反应(RT-PCR)进行毒株分型鉴定；杯状病毒、腺病毒和星状病毒采用多重RT-PCR或PCR进行检测，对PCR阳性标本克隆和测序进行型别鉴定。结果：257份标本中共检出189(72％)例至少有一种病毒感染。四种病毒检测阳性率依次为：轮状病毒60.7％(156／257)，腺病毒5.4％(14／257)、杯状病毒5.1％(13／257)、星状病毒5.1％(13／257)。其中混合感染的病例数占3.5％(9／257)。轮状病毒毒株G血清型分型结果为G1型(61.5％)、G3型(25.0％)、G2型(3.2％)、G9型(2.7％)，不同G型混合感染(3.2％)，未能分型(4.5％)；P基因型分型结果为：P[8](75.6％)、P[4](3.8％)、P[4]+P[8]混合感染一份(0.64％)，未能分型31份(19.9％)。G血清型和P基因型组合P[8]G1(65.0％)，P[8]G3(26.0％)，P[4]G2(2.4％)，P4G1(1.6％)。杯状病毒分型结果显示93％属于诺如病毒GⅡ组，扎如病毒1例。14例腺病毒(Ad)感染分属于腺病毒A、C、F三个亚属，血清型分别是Ad12、Ad18、Ad2、Ad6、Ad40、Ad41。13例星状病毒感染血清型均为1型。病毒性腹泻的高发季节轮状病毒最为明显为9-12月份。发病年龄主要为2岁以下婴幼儿，轮状病毒的高发年龄是6-23月。杯状病毒、腺病毒和星状病毒感染未表现出明显的季节性。结论：病毒因子是兰州地区婴幼儿腹泻的主要病原。轮状病毒是兰州地区婴幼儿病毒性腹泻的最主要病原，杯状病毒、腺病毒和星状病毒也是本地区婴幼儿病毒性腹泻的重要病原。本年度轮状病毒的主要流行株为G1P[8]，与往年明显不同。更多还原

【Abstract】 Backgroud: Gastroenteritis disease is a major cause of childhood morbidity and mortality; especially in developing countries.Globally almost 1.5 to 2 million infants and young children are believed to die of gastroenteritis-related disease or complications every year. Enteric virus have been recognized as the most important etiologic agents of disease, and four categories of viruses are now considered as clinically important including rotavirus,calicivirus,adenovirus and astrovirus. Rotavirus is recognized to be the single most important etiological agent associated with severe dehydrating gastroenteritis. Each year, rotavirus causes approximately 440,000-6000, 000 deaths in children <5 years of age. Rotavirus Vaccine is the single effective method to prevent and control rotavirus diarrhea morbidity and mortality. The fluctuations of predominant strains depending on the area and the year studied have confirmed the importance of long-term and systematical surveillance in a variety of geographical settings and provided important considerations for the development and implementation of an effective vaccine.Objective: To study molecular epidemiology of four major etiological viruses among children with diarrhea in Lanzhou, Gansu province, and to provide the theory evidence for prevention and treatment to virus diarrhea.Methods: A total of 257 stool specimens were collected from children less than 5 years old with acute gastroenteritis admitted in the First Hospital of lanzhou University from July 2005 to June 2006. Dako IDEIA^TM kits were used for detection of rotavirus, further strain characterization of rotavirus was carried out with reverse transcription-polymerase chain reactions （RT-PCR）.The detection of calicivirus, adenovirus and astrovirus were done by multiple （RT-） PCR. The PCR products （DNA） positive for samples of norovirus, adenovirus and astrovirus were analyzed by nucleotide sequencing, respectively.Results: At least one viral agent was found in 72% （186/257） of the specimens. Rotavirus was detected in 60.7 （156/257） of cases, adenovirus 5.4%（14/257）, calicivirus 5.1%（13/257）,astrovirus5.1%（13/257） respectively. Dual infections were found in 3.5 %（9/257） of all samples. Among 156 rotavirus positive samples, serotype G1 （61.5%）was the most predominant strain followed by G3（25.0%）、G2 （3.2%）、G9 （2.7%）, and mixed-G infection （3.2%）, 4.5% of strains remained to be non-typeable.P genotyping showed P[8] （75.6%） was most common followed by P[4] （3.8%） ,mixed-P infection（0.64%）, nontypeable 19.9%.Strain P[8]G1（65.0%） was the most common combination followed by P[8]G3（26.0%）,P[4]G2（2.4%） and P4G1（1.6%）。The overall prevalence of calicivirus infection was 5.1 % with 93% of the strains belong to the norovirus G II genera. Sequence analysis showed that adenovirus detected in this study belonged to three distinct subgenera（A,C,F）with six serotypes（Ad12,Ad18, Ad2,Ad6, Ad40,Ad41）.A total of 13 astrovirus strains were all belongs to astrovirus type 1.A peak admission of rotavirus diarrhea was observed from September through December .More than 94.87% of rotavirus diarrhea patients under hospitalization occurred among children younger than 2 years. The incidence rates of rotavirus were highest in infants aged 6-23 months.Conclusion: Enteric viruses were confirmed as the most common cause of acute gastroenteritis among infants and children in lanzhou.Rotavirus was the most important pathogen for viral gastroenteritis followed by adenovirus, norovirus and astrovirus.The predominant rotavirus strain circulated was P[8]G1,which was different from the finding in the previous years.更多还原