高县某中、小学甲肝暴发疫情调查

目的查明甲肝暴发原因及传播途径,分析流行因素,制定控制措施,评价控制效果。方法对每例患者进行个案调查和三间分布;调查47名住院患者甲肝疫苗接种情况。结果本次甲肝暴发疫情集中在该镇中、小学、幼儿园共发病65人,18岁以下青少年占发病的98.46%(64/65),65名患者甲肝疫苗接种率为0。结论此次甲肝暴发的传播途径为日常生活接触,及时采取措施、加强对学校内外环境消毒、杀虫和健康教育知识宣传,密切接触者及时采取丙球应急接种,易感人群接种甲肝疫苗是控制甲肝暴发的有效措施。     

2010年务川县甲肝暴发疫情调查分析

目的分析2010年贵州省务川县甲肝暴发疫情可能的危险因素和传播途径,评价控制效果。方法采用统一的调查表对病例进行调查核实,了解病例的三间分布。结果 2010-01/08年共报告甲肝病例34例,报告病例来自大坪镇甘禾村塘池组及相邻的黄洋村陈家山和石院子组,罹患率0.11%;甘禾小学发病18例,罹患率2.96%。密切接触者隐性感染率20.51%,发病年龄以7~13岁较多,占52.94%,人群以学生（20例）及散居儿童（8例）发病较多,占82.35%,该镇2岁以上人群均无甲肝疫苗接种史。结论该起疫情系通过生活密切接触传播引起,发病地点主要为农村小学,应改善农村环境卫生开展健康教育宣传和甲肝疫苗应急接种,有效控制甲肝暴发。     

一起甲肝暴发疫情的流行病学调查

目的 查明暴发原因和传播途径,分析流行因素,评价控制效果,评价甲肝疫苗接种效果.方法 用病例对照的方法探索该校甲肝暴发流行病学因素.结果 查出该校学生甲肝23例,平均罹患率6.18%.结论 建议广泛开展中、小学生健康教育,严格管理甲肝传染源,努力做到饮用水和食品卫生;继续做好甲肝疫苗在小年龄组的接种工作.     

宁波市江北区儿童甲肝疫苗免疫效果评价

我区历年疫情报告资料显示甲型肝炎暴发是影响我区病毒性肝炎发病高峰的主要原因 ,1997年开始在 2 4月龄以上儿童中开展甲肝疫苗免疫接种。为较全面分析我区甲肝疫苗接种状况 ,客观地评价甲肝疫苗初免后血清学及流行病学效果 ,现将结果报告如下。材料与方法1　资料来源　儿童甲肝疫苗接种率报告和现场调查资料来源于江北区甲肝疫苗接种报告系统上报资料 ,数据由江北区内各卫生院上报的档案资料。现场调查资料为宁波市卫生防疫站 2 0 0 0年对江北区 2 4月龄儿童甲肝疫苗接种率抽查资料。江北区 1990～ 2 0 0 0年甲肝疫情资料 ,来源于江北区历…     

四川省1起甲型肝炎暴发的流行病学分析

目的探讨四川省阆中市西山中心校甲型肝炎(甲肝)暴发因素和控制措施.方法应用描述性流行病学方法对西山中心校甲肝暴发疫情进行分析.结果本次甲肝暴发,发病77例,罹患率120.1‰.发病年龄主要集中在11～16岁(占77.92%),患者中有55例(71.43%)为住校学生,住校生罹患率是走读生的3.64倍.结论报告迟缓,疫情蔓延历时54 d,而学生普遍未进行甲肝疫苗接种,造成易感人群的大量积累是本次暴发的直接原因.     

东营市 2005 年甲肝疫苗查漏补种效果分析

为防止甲肝的暴发和流行,提高人群免疫力,保护儿童和青少年身体健康,我们于2005年对东营市全市范围内的1～15岁儿童进行甲肝疫苗查漏补种,现将结果报告如下。1材料和方法1.1材料来源东营市2005年甲肝疫苗查漏补种资料;2004-2006年法定传染病报告系统甲肝病例数据。1.2统计学分析方法应用Excel软件进行统计分析。2结果2.1接种的组织与实施2.1.1确定甲肝疫苗接种的目标儿童:分析最近5年甲肝发病的流行病学资料,15岁以下儿童是甲肝发病的高危人群,近20%的病例集中在学龄儿童。从2004年接种率调查情况看,全市4岁以下儿童甲肝疫苗接种率仅为67.4…     

1起甲肝暴发疫情的调查

目的为了解1起甲肝疫情,查找疫情的相关危险因素,控制疫情的继续蔓延提供科学依据。方法建立病例定义,开展病例搜索、个案调查和现场流行病学调查,采集密切接触者血清标本及患者家庭水标本,进行现场接种率调查。结果共发现甲肝病例10例,罹患率为3.85%;发病主要集中在9~10月,占病例总数的70.00%;男性7例,女性3例;发病年龄为4~17岁,其中6~11岁占总病例的70.00%;职业以学生为主;病例主要集中在该村小学,有3个家庭聚集(8例病例),6人有同学关系;密切接触者隐性感染率23.08%;调查甲肝疫苗接种率62.50%。流行曲线提示为人传人增殖模式暴发。结论该疫情是由于医院监测敏感性低,未及时诊断隔离病人,发病年龄人群卫生习惯差,免疫接种率不高引起的日常生活接触传播。     

一起农村幼儿园甲型肝炎暴发的流行病学调查分析

2004年4月20日-5月29日．焦作市武陟县西陶镇发生了一起以一所幼儿园为中心的甲型肝炎(以下简称甲肝)暴发。40天的流行期内。该幼儿园儿童共发病42例．罹患率为12．81％(42／328)，同期全镇共报告甲肝病例69例．10岁以下儿童罹患率为1．32％(69／5249)。经调查证实是一起以幼儿日常生活接触为主要传播途径的甲肝暴发疫情。现将本次疫情的流行病学调查结果分析如下：     

一起农村小学甲型肝炎暴发的调查分析

目的调查分析一起农村小学甲肝暴发的原因和流行特点,探讨农村学校甲肝预防控制对策。方法开展患者个案调查和病例对照研究,并采样进行实验室检测。结果疫情持续92 d,共发病21例,罹患率为2.01%,校内及周边食品摊点共9家,其中6家为无证经营,销售的散装麻辣小食品细菌总数、大肠菌群均超过国家标准,经常食用该食品者甲肝发病危险性显著高于不食用者(OR=120,χ2=27.78,P<0.01)。校外租房生甲肝罹患率显著高于寄宿生(χ2=6.87,P<0.01)。结论此次甲肝暴发的原因以经常食用污染严重的散装麻辣小食品为主。加大农村食品、饮水卫生执法力度,强化“四早”,提高甲肝疫苗接种率和加强学校健康教育工作是防止农村中小学甲肝暴发流行的主要措施。     

中缅边境县一起甲型病毒性肝炎暴发的流行病学调查分析

目的调查分析2015年云南省中缅边境的镇康县一起甲型病毒性肝炎(甲肝)暴发疫情流行特征和原因,提出针对性预防控制措施。方法采用现场流行病调查、病例对照设计等方法收集甲肝发病和相关影响因素数据,进行流行病学分析。结果 2015年4月4日至9月15日镇康县报告本地和缅甸籍甲肝病例75例,发病率为83.65/10万。2个自然村寨和1所村小学发病呈聚集性。入境缅甸边民较多的南伞镇本地感染病例的发病率显著高于其他乡镇(x~2=36.65,P=0.000)。本地感染病例中0-9岁儿童发病构成(13.16%)显著低于缅甸感染病例中同年龄儿童的发病构成(45.16%)(x~2=8.76,P=0.003)。本地感染病例以学生为主(50.00%),缅甸感染病例以散居儿童为主(45.16%)。本次暴发可能与食物污染有关,并存在人-人传播模式。结论中缅边境县甲肝发病从缅甸传入传播的风险较大,加强甲肝疫苗接种、及时发现和处置聚集性疫情是控制甲肝暴发的有效手段。     

Hepatitis A control in a refugee camp by active immunization

An outbreak of hepatitis A occurred among children of a refugee camp in Croatia. In order to disrupt the outbreak, we decided to vaccinate children from 1 to 15 years of age in the camp, in addition to intensified general preventive measures. Assuming high prevalence of hepatitis A virus antibodies within this population, we conducted anti-HAV testing of the children eligible for vaccination. Of 108 children tested, 74 (68.5%) were anti-HAV positive. We vaccinated 34 children. One month after vaccination 31 previously negative children were tested for anti-HAV and 30 of them were found positive, suggesting a seroconversion rate of 96.8%. One child fell ill 5 days after vaccination, after whom no new cases of hepatitis A occurred. Thus we conclude that active immunization is a successful means of stopping an outbreak of hepatitis A.     

Vaccination against hepatitis A during outbreaks starting in schools: what can we learn from experiences in central Italy?

Two outbreaks of hepatitis A started almost simultaneously in a maternal school and in a day care centre located at opposite sides of Florence, Italy, at the end of 2002. Both of them originated from immigrant children, and in both cases, hepatitis A was initially not recognised due to aspecific symptoms. While vaccination of contacts started with delay in the first outbreak, the same intervention was organised and performed in 3 days in the other. The outbreak starting in the maternal school caused 30 notified cases, plus 7 cases diagnosed retrospectively. Nine of them were in a secondary school, where vaccination (in accordance with the Italian national guidelines on hepatitis A (HA) vaccination) had been started only after a secondary case occurred. Only three cases occurred overall in the other outbreak starting in the day care centre, where >80% of infants, children and personnel were immunised. Although few asymptomatic infections probably occurred, no source of contagion existed any longer 2 months after immunisation. A rapid vaccination of school and family contacts of hepatitis A cases after the first case (irrespective of school grade) seems to play an important role to shorten outbreak duration.     

Experience of hepatitis A vaccination during an outbreak in a nursery school of Tuscany,Italy.

An outbreak of hepatitis A started in late October 1996 in a nursery school in Tuscany, Italy. A programme of hepatitis A vaccination without the use of immunoglobulin started at the beginning of December 1996 and included 33 children, 21 household contacts and 6 adults working in the school. Overall, 11 cases occurred in children attending the school (attack rate 27%) and 10 among their household contacts (attack rate 9 %). The latter also included parents, and, in two cases, grandmothers. The data indicate that susceptibility to HAV has increased over recent decades in central Italy. Past and recent experience shows that the usual duration of hepatitis A epidemics in the absence of immune prophylaxis is longer than that described here. The use of hepatitis A vaccine probably contributed to the early extinction of the outbreak, because no further cases were notified in the area after 7 February 1997.     

Vaccination strategies for control of community outbreaks of hepatitis A: A comparison of two outbreaks in England

In August 2015 two community outbreaks of hepatitis A virus (HAV) occurred in sub-urban communities in Northern England. Each was managed by an independent outbreak control team. In outbreak one, mass vaccination was deployed targeting a residential area and two schools, while in outbreak two, vaccination was reserved for household-type contacts of cases. The highest vaccination uptake was achieved in the school settings (82% and 95%). These case studies illustrate the range of approaches that can be used and the factors that influence decision-making in response to a hepatitis A community outbreak. Both outbreaks likely started from importation(s) of HAV by returning travellers and spread through extended social networks and the local community. Vaccination strategies were selected based on hypotheses about transmission pathways, which were informed by evidence from oral fluid (OF) testing of asymptomatic contacts. More evidence about the effectiveness of mass vaccination in community outbreaks of hepatitis A in low endemicity settings is needed. Hepatitis A guidelines should include recommendations for the use of mass vaccination and OF testing in outbreaks.     

Salivary antibody testing in a school outbreak of hepatitis A.

During a community-wide outbreak of hepatitis A in Gloucester, UK there was a high attack rate in children attending two city primary schools and a pre-school centre sharing the same site. In September 1990, saliva specimens were collected from 478 (85%) of the 562 children. The prevalence of antibody to hepatitis A virus (anti-HAV), as determined by saliva testing, was 29.6%; highest prevalences were seen in 5-6-year-olds and in children from that area of the city at the centre of the community-wide outbreak. The proportion of immune children with a history of clinical hepatitis varied with age from 1 in 42.7 of under-5-year-olds to 1 in 4.7 of 8-10-year-olds. Six children who received prophylaxis with human normal immune globulin (HNIG) because they were household contacts of cases subsequently became infected. Since there was evidence of transmission outside the school environment it is unlikely that a policy of universal prophylaxis within the schools would have stopped the outbreak. Mass prophylaxis in school outbreaks is only likely to be effective if most transmission is occurring at school and if the target population can be clearly defined. Salivary antibody testing is a simple, practical and acceptable procedure in young children. Salivary antibody surveys in conjunction with vaccination against hepatitis A should provide a cost-effective method for control of future outbreaks.     

甲型肝炎减毒活疫苗在甲型肝炎爆发中的保护效果

目的 探讨国产Ｈ２株甲型肝炎减毒活疫苗在甲型肝炎爆发中的保护作用。方法 疫苗接种采用非随机对照设计分组,以小学１～３年级及部分学前班儿童５５５１人为对象。效果考核采用流行病学和血清学分析,抗－ＨＡＶ ＩｇＭ检测采用ＥＬＩＳＡ法。结果 疫苗接种１年后发生甲型肝炎爆发,观察对象中发生２６例甲型肝炎,相关村疫苗组发病率０．２８％（１／３５６）,对照组发病率５．９２％（２５／４２２）,疫苗保护率９５．２７     

Hepatitis B vaccination for injection drug users--Pierce County, Washington, 2000

Hepatitis B vaccination has been recommended for injection drug users (IDUs) since 1982, but vaccination coverage of IDUs remains low (1), and outbreaks of hepatitis B among IDUs continue to occur. An outbreak of hepatitis B primarily among IDUs in Pierce County, Washington, detected in April 2000, included 60 cases and resulted in three deaths among IDUs co-infected with hepatitis delta virus. A program to administer hepatitis B vaccine to IDUs was implemented to control the outbreak, and the number of cases identified decreased from 13 per month in May to two cases since November. This report describes a vaccination program during which IDUs accepted hepatitis B vaccination provided free of charge in community-based settings and illustrates how effective hepatitis B vaccination programs targeted at IDUs can be implemented through collaborations between departments of health and corrections and community organizations.     

江苏省甲肝防治对策及其效益评估

流行病学调查显示,始于１９８８年江苏省病毒性肝炎高发是由甲型肝炎春季流行高峰所致。其危险因素包括：人群甲肝抗体水平降低、生食海产品和有接触史等。为使发病强度得到控制,自１９９４年起采用以接种甲肝疫苗为主导措施的防治对策,每年全省开展“压春峰”活动。该对策取得显防病效果,６年间共减少发病６５２８７９例,发病强度从全国第一位降至全国平均水平以下,急性肝炎病例中甲肝病例比例下降,甲肝爆发点显减少,６     

Active immunisation during an outbreak of hepatitis A in a German day-care centre

During an outbreak in a German day-care centre (DCC) caring for 100 children HAV vaccination was recommended for children, employees and household members of cases. A retrospective cohort study was done to evaluate vaccine uptake and identify possible risk factors for disease. Between 19 December 2004 and 30 January 2005 eight DCC children and seven household members fulfilled the case definition, i.e. had clinical hepatitis (14) or were diagnosed with asymptomatic HAV infection (1). Following the recommendation to vaccinate, given on 23 December 2004, 66.7% (46/69) of DCC children, 15.8% (29/184) of household members and 5/5 of employees were vaccinated, and three vaccinated children and two not vaccinated children fell ill. One of 11 children who received human normal immunoglobulin (HNIG) and four of 58 children who did not receive HNIG fell ill. In households in which the DCC child received HAV vaccine and/or HNIG, seven (5.6%) of 125 household members fulfilled the case definition. In households of non-immunised children none of the 59 household members fell ill. We conclude that, although most vaccinations were administered promptly, they may not have been timely enough to impact the course of the outbreak.