Preparing IR for COVID-19: The Singapore Experience

This paper describes country-wide special measures undertaken for interventional radiology staff during the current coronavirus disease 2019 (COVID-19) pandemic. Although each interventional radiology service around the world faces unique challenges, the principles outlined in this article will be useful when designing or strengthening individual practices and integrating them within wider hospital and national measures. Moving beyond the current outbreak, these measures will be useful for any future infectious diseases which are likely to arise.     

Utility of whole-cell repetitive extragenic palindromic sequence-based PCR (REP-PCR) for the rapid detection of nosocomial outbreaks of multidrug resistant organisms: Experience at a tertiary care center in North India

Background: There is a huge need to develop molecular typing methods which are simple to perform, rapid and cost effective to confirm clonality of nosocomial isolates in outbreak situations. Objectives: The aim of the study was to investigate a hospital outbreak of multi-drug resistant (MDR) Klebsiellapneumoniae septicemia in a paediatric surgery intensive care unit (PSICU) using a repetitive extragenic palindromic polymerase chain reaction (REP-PCR). Materials and Methods: MDR Klebsiella pneumoniae isolates from an outbreak of nosocomial sepsis were typed byREP-PCR using consensus primers. Isolates from different intensive care units (ICUs) but with similar antibiogram were also genotyped for comparison. Results and Conclusion: A cluster of twelve MDR K Pneumoniae septicemia cases was identified at the PSICU by genotyping using REP-PCR. Surveillance cultures failed to pick up any source of infection. REP-PCR was found to be a rapid and simple tool for investigation outbreaks in hospitals. Due to early detection we could initiate infection control practices with focus on hand washing and prevent the further transmission of the organism.     

Hospital outbreak caused by a carbapenem-resistant strain of Acinetobacter baumannii: patient prognosis and risk-factors for colonisation and infection

Between October 2001 and August 2002, 30 hospital patients became infected or colonised by a multiresistant (including to carbapenems) epidemic strain of Acinetobacter baumannii (AbMR) in a hospital outbreak. This study analysed the risk-factors associated with acquisition of this epidemic strain and investigated the prognosis of patients infected by AbMR, with the aim of elucidating factors which lead to mortality. A case-control study of the acquisition of AbMR in patients infected or colonised in the hospital outbreak was performed. Independent risk-factors leading to death were studied by logistic regression analysis. Multivariate analysis of the risk-factors for colonisation/infection with AbMR revealed an independent association with the presence of an arterial catheter (OR, 1.13; 95% CI, 1.03-1.25) and administration of imipenem as monotherapy (OR, 11.12; 95% CI, 2.33-53.09). Multivariate analysis of the prognostic features leading to mortality revealed a significant association with hypotension or shock (OR, 24.63; 95% CI, 1.56-387.56) at the time of bacterial isolation.     

An outbreak of Pneumocystis carinii pneumonia in children with malignancy

An outbreak of Pneumocystis carinii pneumonia (PCP) in three patients within a 6 week period was reported. Two patients had acute lymphoblastic leukaemia and one had brain-stem glioma. They shared common features of immuno-suppression and absence of cotrimoxazole prophylaxis and had been nursed in the same room. The severity of PCP and its response to treatment may be related to the degree of immunosuppression. Because of the morbidity and mortality of PCP, chemoprophylaxis should be given to all at-risk cases. Furthermore, isolation of patients with PCP should be considered in view of increasing evidence of nosocomial transmission.     

山东省中小学生麻疹爆发原因的病例对照研究

为探讨山东省中小学生麻疹爆发的原因 ,采用 1∶2配比的病例对照方法对中小学生麻疹疫苗 (MV)效力进行了研究 ,同时对近年来中小学生MV接种率进行了估算。结果显示 :中小学生MV效力为 74 % ,95 %可信区间为4 7%～ 88% ;小学生MV效力明显高于中学生 ,分别为 82 %和 6 8% ;1999～ 2 0 0 1年学龄儿童的估算接种率分别为75 4 %、75 6 %和 5 5 7%。较低的MV效力和接种率是计划免疫工作薄弱地区中小学生麻疹爆发的主要原因。     

四川省绵阳市2019—2021年流行性感冒流行病学特征分析

目的 了解绵阳市2019—2021年流行性感冒流行病学特征,为绵阳市流感防控工作提供重要依据。方法 收集绵阳市2019—2021年流感监测相关数据,采用描述性流行病学方法进行统计学分析。结果 绵阳市2019—2021年流感共报告发病55 970例,年均报告发病率388.08/10万。报告流感样病例（influenza-like illness cases, ILI） 103 723例,年平均ILI%为3.58%。2019年流感报告发病率、ILI%、阳性检出率均远超过历年同期水平。人群分类构成以15岁以下学生为主。报告发病数居前三位的地区分别为涪城区20 118例（占35.94%）、游仙区6 394例（占11.42%）、江油市5 800例（占10.36%）。2019—2021年共收到并检测ILI标本10 126份,阳性率19.53%;标本阳性检出率以15岁以下学生为主。历年流感病毒优势毒株呈现出交替流行的趋势,2019年以A（H3）型为主,2020年受新冠疫情影响,全年阳性检出率均较低,2021年除检出2份A（H9）型外,其余均为BV型。2019—2021年共报告ILI暴发疫情43起,发生时间主要集中在冬季,场所以小学居多。结论 2019—2021年绵阳市流感病例、ILI、病原学监测、暴发疫情的特征基本一致,15岁以下的学生及学校仍为重点关注人群及场所。而新型冠状病毒肺炎疫情大流行下,流感的低发水平进一步印证非药物干预措施对流感防控工作的重要性。     

一起工厂伤寒爆发疫情的流行病学调查与分析

目的探讨伤寒疫情的规模及原因,以便及时采取科学、合理的疫情控制措施。方法采用病例对照研究方法开展此次疫情调查,比较病例与对照之间不同危险因素的暴露比例,并采集工厂内外环境、饮食及水源的相关样本进行检测。结果共报告28例伤寒确诊病例,无死亡。对病例中分离的12株伤寒菌株进行的PFGE检测结果一致。病例分布在该片区217间工厂中的10间,平均罹患率为3.1‰,工厂间的罹患率无统计学意义（χ^2=5.2,P=0.74）。在危险因素的单因素及多因素分析中,病前外出进餐史（OR=8.0,95%CI：2.6～25）、病前凉面或凉皮进食史（OR=6.8,95%CI：1.4～32）及直接引用生水史（χ^2=4.9,P〈0.01）等危险因素结果一致,均有统计学意义。在所有40份环境样本中,水箱水、井水及水箱底泥水均发现有粪大肠菌群超标现象,但未分离到伤寒沙门氏菌。结论此宗伤寒可能是由于饮用污染的井水和在凉面、凉皮制作过程中使用污染井水导致的。采取加强饮食卫生管理、隔离治疗病人及带菌者、停止使用井水而改用市政供水等措施之后疫情终止。     

广州增城市一起输入性登革热暴发的流行病学调查分析

目的分析广州增城市2006年一起输入性登革热暴发的流行病学特征，为制定预防控制措施以及在暴发疫情中进行索源调查提供科学依据。方法采用流行病学调查和回顾性病例搜索，对该起登革热疫情调查分析；采用间接免疫荧光法对病例血清进行登革热抗体检测；用布雷图指数（BI）进行蚊媒密度调查。结果病例刘某为实验室确诊病例，无外出史；索源调查发现的病例黄某及其侄子血清登革热IgM、IgG均阳性，有疫区活动史，发病时间与刘某发病在一个潜伏期内。结论该病例为增城市2006年首例报告登革热确诊的本地感染病例，感染来源为区外输入性；早期被误诊，传染源未被及时发现是导致本次疫情的重要原因；迅速灭蚊和消除伊蚊孳生地是控制疫情的有效措施；多部门参与、组织专业队及时扑救疫情是迅速控制登革热流行的幸兽原因．     

广州市一起登革热家族聚集性暴发事件的调查与分析

目的探讨登革热家庭聚集性发病的流行病学特点及传播效率，为今后进行有效的预防和控制登革热暴发提供参考。方法采用现场流行病学调查方法对广州市一起登革热家庭聚集性暴发事件进行调查和分析；采用ELISA、RT-PCR和病毒分离的方法对标本进行检测。结果2006年8月广州市荔湾区发生一起登革热家庭聚集性暴发事件，该家族15名家庭成员先后共有6人发病，罹患率40．0％，其中6例患者登革热抗体IgM或IgG阳性3例，病毒分离阳性3例，荧光PCR检测阳性者1例，基因序列测序和病毒分离结果最终确定为登革I型病毒。结论根据临床表现、实验室检测结果以及流行病学调查．虽然该家族部分患者登革热抗体为阴性，但病例发病均在一个最长潜伏期内，因此可以确定该家族发生了登革热聚集性暴发，荔湾区龙津中路龙兴里最有可能是共同感染地．感染来源不明，感染时间为家庭聚会日可能性大。     

Cloning and characterization of the cDNA encoding the HA protein of a hemagglutination-defective measles virus strain

cDNA clones corresponding to the mRNA for the hemagglutinin of the hemagglutination-defective strain AK-1 of measles virus were isolated and characterized. Compared with the prototype Edmonstron strain, 60 nucleotide substitutions that resulted in 18 amino acid changes were detected. An additional potential N-linked glycosylation site was added by point mutation, which was supported by the observation that the hemagglutinin of the AK-1 strain was stained more heavily after NaDodSO₄PAGE and periodic acid-Schiff (PAS) staining than the Edmonston strain. Computer-assisted analysis revealed that three reverse turns in the secondary structure had disappeared in the hemagglutinin of the AK-1 strain. Moreover, one of these structural changes occurred in the closely glycosylated region at amino acid residues 168–240, which appeared to be a biologically important functional domain. The isoelectric point calculated from the predicted amino acid sequence became about 1 pH unit more basic in the AK-1 strain than the Edmonston strain. This present study is the first sequence analysis of the hemagglutinin gene in a hemagglutination-defective strain of the measles virus.