一起学校水痘暴发的现场流行病学调查

目的核实疫情,确定J学校水痘暴发的存在并描述疫情三间分布特征和流行强度,探讨发病危险因素。方法按照病例定义,开展病例搜索,描述其三间分布后,结合现场流行病学调查情况,形成假设,再采用回顾性队列研究方法验证假设。结果 2009年3月1日至4月28日搜索到符合病例定义的病例共45例。首例病例于4月2日发病,全校分别于4月8日、16日、21～27日出现3个发病高峰。二（4）班和二（5）班罹患率最高,分别为33.3%和27.1%。45例病例均为学生,男生罹患率为7.2%,女生罹患率为4.8%。7～10岁组38人,占84.44%。在全校学生中乘坐校车者发生水痘的危险是不乘坐校车者的2.3倍（RR=2.36,95%CI=1.29～4.32）。按不同年级进行的Mantel-Haenszel分层分析表明：乘车与不乘车2个队列之间罹患率差异有统计学意义（χ2=4.32,P〈0.05）。结论根据病例临床表现、三间分布特征,确定J学校存在水痘暴发;年级不是混杂因素,乘坐校车会增加水痘发病的危险性。     

青海省某学校流行性腮腺炎暴发的流行病学调查

目的 了解分析学校流行性腮腺炎暴发的流行病学特征及发生原因,为今后的防病工作提供参考.方法 对疫情资料进行描述性流行病学分析.结果 2013年9月22日发现首发病例,截止10月17日,共发病43例.罹患率为6.23(43/690).流行曲线呈双峰型,病例出现班级聚集性.100％的患者无相关疫苗免疫史.实施应急接种后,疫情得到有效控制.结论 疫情迟报、病例未严格隔离、疫苗接种率低、易感人群积累是造成流行性腮腺炎暴发的主要原因.提高人群免疫接种率是防止暴发的主要措施.     

西藏自治区尼玛县一起导致3例死亡病例的水痘暴发疫情分析

目的 查明此次水痘疫情暴发的传染来源、传播途径和感染危险因素,为有效防控疫情提供科学依据.方法 本次暴发调查的病例定义为:2010年11月7日以来,尼玛县吉瓦乡四村当贡自然村的村民中,出现发热(腋下温度≥37.3℃或自述发热者)伴有皮疹者.应用调查问卷搜集病例信息,主要内容包括基本信息(年龄、性别、住址)、发病时间、临...     

某幼儿园一起手足口病暴发的现场流行病学调查报告

目的了解某幼儿园手足口病暴发的流行病学特征及造成传染的主要原因,为进一步做好该园手足口病防控工作提供依据。方法按照病例定义,电话开展病例搜索,结合现场流行病学调查情况,形成假设,采用1：2匹配的病例对照研究,对照选取同班同年龄组同性别的儿童,使用统一的调查表询问儿童的日常卫生习惯。结果该幼儿园从2010年3月16日至3月23日共发生9例临床诊断病例,3例实验室确诊病例,罹患病率为7.95%。以小班病例为主,3～4岁组比例高（8/12）。3份粪便检测出病原体CoxA16。有吸吮手指、吸吮玩具、饭前不洗手、便后不洗手、挖鼻孔、揉眼睛等任一不良卫生习惯是手足口病发病的危险因素（OR=12,95%CI=1.3～114）。结论幼儿不良卫生习惯是该幼儿园手足口病传播的主要原因。建议该园加强儿童不良卫生习惯的纠正,培养良好卫生习惯,以达到控制传染的目的。     

一起风疹暴发的发病因素调查

目的 了解风疹暴发的发病有关因素。方法 对一起风疹暴发进行流行病学的调查分析。结果 8-12岁未接种风疹疫苗者,是风疹暴发的最危险的易感人群,实行风疹疫苗的接种,能有效的控制风疹的流行,结论 预防策略是：对14岁以下的人群进行普遍免疫,对儿童进行常规免疫,有条件的城镇对婚前检查的妇女也进行免疫。     

河北邯郸某学校隐翅虫皮炎暴发的流行病学调查

2008年9月10日,河北省邯郸市磁县岳城镇中学发生一起急性皮炎暴发事件,到调查结束时共发病100人,罹患率为13．3％。经现场调查和采集昆虫样本,结果显示此次急性暴发性皮炎为隐翅虫皮炎暴发,原因是学校地处郊外,教室无纱窗及门帘,学生晚自习采用日光灯照明,经采取灭虫等有效控制措施后,疫情得到控制。     

关于一起戊肝暴发情况的调查

2007年2月23日接到报告,有3例戊肝病人住院且属同一单位.根据流行病学调查患者临床表现及实验室检验分析,证实为一起戊肝暴发.现将此次暴发调查处理情况报告如下.     

阳江市一起基孔肯雅热暴发疫情流行病学调查

目的了解基孔肯雅热的流行特征,探索有效的防控策略,为今后防控工作提供依据。方法根据病例定义进行病例搜索,对符合病例定义的病例进行流行病学调查;采用酶联免疫吸附试验方法检测登革热病毒IgM和IgG抗体;采用实时荧光定量逆转录聚合酶链反应方法检测登革热病毒核酸和基孔肯雅热病毒核酸。结果 2010年9月12日至10月21日,阳江市某建筑工地发生基孔肯雅热病27例,总罹患率为11.07%（27/244）;其中男性17例,占62.96%,女性10例,占37.04%;检测15份恢复期病例血样登革热病毒IgM和IgG抗体,其中2份病例血样IgM抗体阳性,其余13份为阴性,15份病例血样IgG抗体均为阴性;检测5份现症病例血样,登革热病毒核酸均为阴性,2份基孔肯雅热病毒核酸阳性。结论这是一起基孔肯雅热暴发疫情,加强出入境检疫、开展医疗机构症状监测和控制传播疾病的媒介密度是预防控制孔肯雅热的重要措施。     

一起诺如病毒感染性腹泻暴发疫情流行病学调查

目的了解一起诺如病毒感染性腹泻暴发的特点和流行原因，探讨暴发疫情调查处理的经验，为制定防治对策提供科学依据。方法对开平市月山镇一起诺如病毒暴发疫情用流行病学方法进行分析。结果该镇水井片11月25日至12月5日共发生感染性腹泻238例，罹患率4．18％；患者各年龄组均有发病，青壮年居多；患者大多呈腹泻、呕吐等胃肠炎症状，病情较轻；对搜索到的575户2347人进行发病聚集性分析，发现有明显的家庭聚集性；不同村委会发病差异有统计学意义。部分病人粪便标本经检测诺如病毒阳性。疫情经加强饮用水消毒、病人隔离治疗、开展爱国卫生运动和健康教育等综合措施后得到控制。结论本起暴发疫情由诺如病毒感染引起，供水系统受到一过性污染是引起水源性暴发的主要原因。加强饮用水的消毒与管理，开展健康教育是控制疫情的关键。     

广州市某社区一起登革热暴发流行的调查与控制

目的分析广州市荔湾区2006年某社区登革热暴发的流行病学特征，评价预防控制效果。方法采用现场流行病学调查方法对所有病例进行调查分析，用间接免疫荧光法进行登革热抗体检测，用布雷图指数进行蚊媒密度调查。结果首例发病8月21日，末例9月3日，流行时间14d，共发病74例，罹患率为3、47％，全部病例均在同一潜伏期内发病，未出现第二代病例。实验室检测74例患者中登革热抗体IgM或IgG阳性73例，布雷图指数在采取大规模的综合控制措施前最高达93．4，在采取控制措施后，蚊媒密度达到要求。结论根据流行病学调查和实验室检测结果，可以确定该起疫情是登革热暴发流行。采取以整治环境卫生、迅速杀灭成蚊、清除积水和隔离治疗病人等综合措施后，该社区的疫情在较短时间内得到有效控制。     

一起小学流行性腮腺炎爆发的调查分析

目的核实疫情,确定某小学流行性腮腺炎（简称流腮）暴发的存在并描述疫情三间分布特征和流行强度,探讨发病危险因素。结论按照病例定义,开展病例搜索,描述其三间分布后,结合现场流行病学调查情况,形成假设,再采用病例对照研究方法验证假设。结果某小学2009年5月1日至6月18日搜索到符合病例定义的病例共33例。首例病例5月21日发病,6月14-17日出现发病高峰。二（3）班罹患率最高,为28%。男生罹患率为12%,女生罹患率为9%。病例对照研究表明,在校就餐是危险因素;吃午饭前洗手、平时洗手时使用肥皂是保护因素。结论根据病例临床表现、三间分布特征,确定某小学存在流行性腮腺炎暴发;建议校方减少学生在教室就餐的机会,加强宣传教育,提高学生自我保护意识,养成良好的洗手习惯。     

Epidemiological investigation of a nosocomial outbreak of multidrug-resistant Corynebacterium striatum at one Belgian university hospital

During an 8-month period, 24 Corynebacterium striatum isolates recovered from lower respiratory tract specimens of 10 hospitalized patients were characterized. The organisms were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and by 16S rRNA gene sequencing. The cluster of C. striatum exclusively affected patients who had been admitted to an intensive care unit and/or subsequently transferred to one medium-size respiratory care unit. Prolonged duration of hospitalization, advanced stage of chronic obstructive pulmonary disease, recent administration of antibiotics and exposure to an invasive diagnostic procedure were the most commonly found risk factors in these patients. Seven patients were colonized and three infected. All strains displayed a similar broad spectrum resistance to antimicrobial agents, remaining susceptible to vancomycin only. Typing analysis by MALDI-TOF MS and by semi-automated repetitive sequence-based PCR (DiversiLab typing) showed that all outbreak-associated C. striatum isolates clustered together in one single type while they differed markedly from epidemiologically unrelated C. striatum isolates. Pulsed-field gel electrophoresis (PFGE) profiles revealed three distinct PFGE types among the C. striatum isolates associated with the outbreak while all external strains except one belonged to a distinct type. We conclude that C. striatum is an opportunistic nosocomial pathogen in long-term hospitalized patients and can be at the origin of major outbreaks. The routine use of MALDI-TOF MS greatly facilitated the recognition/identification of this organism in clinical samples and this technique could also offer the potential to be used as an easy and rapid epidemiological typing tool for outbreak investigation.     

A probable outbreak of toxoplasmosis among boarding school students in Turkey

In total, 171 students from a boarding school in Izmir, Turkey, with mild and non-specific symptoms of toxoplasmosis, were screened during September-October 2002. All 171 students were seropositive for Toxoplasma gondii IgG and IgM. Of 43 students tested, 40 (93%) had low IgG avidity. None showed evidence of ophthalmic involvement. The data suggest that T. gondii may spread rapidly in close living conditions, possibly following exposure to cat litter. This is the largest recent outbreak of toxoplamosis described in the medical literature.     

O148 Shiga toxin-producing Escherichia coli outbreak: microbiological investigation as a useful complement to epidemiological investigation

An outbreak of Shiga toxin-producing Escherichia coli (STEC) O148 infection occurred among wedding attendees in France in June 2002. A retrospective cohort study was performed and ten cases were identified, including two adults with haemolytic uraemic syndrome (HUS). The analytical study revealed that > 80% of affected individuals had eaten lightly roasted mutton and poultry paté, but only the consumption of paté tended to be associated with illness (relative risk 3.4; 95% CI 0.8-14.4). Left-overs (cooked mutton and raw offal) and processed foods (paté) from the same batches as served at the party were sampled. Human, food and environmental samples were examined for the Shiga toxin (stx) gene and virulence traits by PCR. Stx-positive samples were cultured for STEC. HUS cases were tested for serum antibodies against 26 major STEC serogroups. An STEC O26 strain (stx1, eae, ehxA) was isolated from one case with diarrhoea, and an STEC O148 strain (stx2c) from one case of HUS. Serum antibodies against O26 were not detected in either of these patients; antibodies against O148 were not tested. Three STEC strains were isolated from the mutton and the offal (stx2c, O148), and two from the paté (stx2c, O-X and O-Y). The isolates from the mutton were indistinguishable from the human stx2c isolate, whereas the paté isolates differed. Although four different STEC strains were identified in patients and foods, the results of molecular subtyping, in conjunction with analysis of food consumption patterns, strongly suggested that this outbreak was caused by mutton contaminated with STEC O148.     

重庆市一起学校麻疹爆发疫情的调查分析

目的调查重庆市潼南县一所小学的麻疹爆发疫情,进行爆发流行病学和疾病传播模式描述,研究爆发危险因素和控制措施。方法对所有疑似病例开展流行病学调查和采集血、咽拭子标本进行实验室检测,同时隔离治疗病例和采取应急接种措施控制疫情蔓延。对收集的数据进行爆发流行病学描述。结果此次爆发中该小学共28名学生罹患麻疹,罹患率为1．7％,病例分布于新校区10个班级,首发病例所在班级幼儿园大三班发病数最多,罹患率10．26％。所有病例均住院隔离治疗,无重症和死亡病例。16名病例无麻疹类疫苗免疫史,首个病例发病后未及时诊断和隔离,导致疫情在学校内蔓延。该小学完成校区全部应急接种,实种2734人,接种率97．79％。塘坝镇与相邻乡镇目标儿童摸底共计12005人,实种11867人,接种率98．85％,无接种异常反应报告。结论降低麻疹发病率和防止学校等集体单位麻疹爆发疫情需保证儿童高质量2剂次含麻疹类疫苗接种率和严格执行入托、入学查验接种证制度,同时应加强疫情预警和提高对爆发疫情的应对能力。     

一起疑似食源性诺如病毒暴发的流行病学调查

目的调查广州市某小学出现多名急性胃肠炎病例的感染来源、传播途径和危险因素。方法按照病例定义开展病例搜索,采用描述性流行病学和病例对照研究方法进行分析;样本采用RT．PCR方法检测诺如病毒核酸。结果2013年3月28～31日,共发生诺如病毒感染性腹泻27例,罹患率为3．31％（27／816）。3月28日14：00—22：00时为发病高峰,病例有班级聚集性,病例对照结果显示饭前洗手（OR=0．13,95％CI：0．03—0．63）和每天洗手次数≥5次（OR=0．26,95％CI：0．10～0．72）为保护因素。采集患者、厨工肛拭子、剩余食物及环境涂抹样等85份标本,其中5份检出诺如病毒GII-4型。结论这是一起由诺如病毒GII-4型引起的急性胃肠炎暴发,暴发原因是带毒厨工污染部分食物所致,以食源性传播为主。     

广州市白云区一起登革热局部爆发流行的新特点

目的分析白云区2010年一起登革热爆发的流行病学新特点,为制定登革热预防控制措施提供科学依据。方法对各医院报告的病例进行流行病学调查,采集病例血清以ELISA法进行登革热IgM/IgG抗体检测,使用布雷图指数（BI）进行蚊媒密度调查,在疫点周围开展病例搜索。结果本次疫情流行历时69d,从8月22日至10月29日。共发病19例,其中男8例,女11例;发病年龄最小16岁,最大82岁,以青壮年为主,20～39岁占42.11%。职业分布以家务待业、离退休人员、干部职工发病较高。19例病例主要分布在方圆500m范围内,实验室确诊12例,检测结果显示,单份IgM阳性的6例,单份IgG抗体阳性的1例,IgM/IgG抗体双阳的有12例。9-10月以来BI持续超5,最高达到41,BI平均数为13.8。结论本次登革热爆发疫情呈现流行时间长、范围大、连续散发的新特点,应引起重视。     

An outbreak of hepatitis A on a hospital ward

An outbreak of hepatitis A has been recognised on a medical ward of a district general hospital. Eleven nurses and one patient were reported to have hepatitis over a period of 18 days in October, 1984. Specific tests for hepatitis A IgM were positive in all cases. Following extensive investigations, the outbreak was traced to a female patient who had recently returned from India and who was incontinent. Her serum, when tested subsequently, showed evidence of recent hepatitis A infection. The implications of this outbreak are discussed.     

Measles outbreak investigation in Dwarahat block of District Almora,Uttarakhand

Background: We report an assessment of measles outbreak during the months of February 2014 to April 2014 in Dwarahat block of district Almora and the response mounted to it. Materials and Methods: An intensive door-to-door search to six measles affected villages in Dwarahat block of district Almora, covering a population of 2,408 was carried out to identify the cases of measles by a rapid response team (RRT). A total of ten blood samples were randomly collected for detecting IgM antibody against measles. For all cases, information on personal details, place of residence, time of onset and status of immunization were obtained. Results: Overall attack rate (AR) was 2.8%. AR among the population of age-group 0–16 was 7.2%. Statistically significant higher AR (16.26%) was seen for the age-group of 0–5 years as compare to 6–10 and 11–16 years of age (AR-8.71, relative risk-0.53, 95% confidence interval-0.32–0.88, P value-0.012 and AR-0.57%, relative risk-0.035, 95% confidence interval-0.00–0.14, P value-0.000, respectively). Males were affected more often than females 35 [59.2%] vs. 24 [40.8%]. Measles-related complications were seen in three children. No death was reported. Of the 10 samples, nine were positive for measles IgM antibodies by enzyme-linked immunosorbent assay (ELISA). Conclusion: The recognition of early warning signals, timely investigation and application of specific control measures can contain the outbreak. The unvaccinated or partially protected human beings serve as the reservoir of measles virus. Hence, there is a need for sero surveillance for measles in Uttarakhand and one catch up measles immunisation campaign to prevent future outbreak.