危重病房耐碳青霉烯酶鲍曼不动杆菌同源性研究

目的探讨杭州市第一医院危重病房耐碳青霉烯酶鲍曼不动杆菌之间的同源性,进行分子流行病学调查,旨在为制定预防和控制其院内感染的措施提供依据。方法收集该院危重病房2005年1月至12月分离到的34株亚胺培南耐药鲍曼不动杆菌。采用全自动微生物分析系统VITEK-AMS60对34株耐碳青霉烯酶鲍曼不动杆菌进行鉴定及药敏;用琼脂稀释法和E-test法测定14种抗菌药物的最低抑菌浓度(MIC),脉冲场凝胶电泳(PF-GE)分析其耐药株的同源性,对碳青霉烯类基因OXA-23型、OXA-24型、IMP型、VIM型基因进行PCR扩增及序列分析。结果PFGE发现34株鲍曼不动杆菌菌株为同一耐药克隆株,在危重病房呈爆发流行。所有对亚胺培南耐药鲍曼不动杆菌明确产OXA-23型碳青霉烯酶,未检出OXA-24、IMP、VIM基因型。34株菌株质粒提取未成功。结论该院同一个耐药克隆株在危重病房不同患者身上流行,可能与行气管插管、呼吸机、氧气湿化瓶、护士手操作有关。     

鲍曼不动杆菌的基因分型及耐药性分析

目的分析上海某综合性医院不同科室来源的鲍曼不动杆菌菌株的同源性及耐药状况,了解鲍曼不动杆菌院内感染流行情况。方法采用重复序列PCR技术（REP-PCR）,对51株临床分离的鲍曼不动杆菌菌株进行基因分型,并用纸片扩散法进行药敏试验。结果51株鲍曼不动杆菌分为13个基因型,其中A型16株,为主要流行型别;C型、D型各6株;M型有5株;E型、F型和G型各3株;B型、H型和K型各2株;I型、J型、L型各1株。药敏试验结果显示分离出的菌株对常用抗菌药呈现出多重耐药的现象。其中对阿米卡星和亚胺培南的耐药性最低,均为33.3%;对头孢唑啉耐药性最高,为100%。结论鲍曼不动杆菌基因的同源性分析表明,该院存在着以A型鲍曼不动杆菌为主的感染流行,估计该型菌株可能以克隆株的形式播散。鲍曼不动杆菌的耐药性很强,应加强其耐药性监测,合理使用抗菌药物。     

鲍曼不动杆菌基因分型技术的研究进展

鲍曼不动杆菌为非发酵糖类革兰阴性杆菌,具有强大的获得耐药性和克隆传播的能力,广泛分布于医院环境,是医院内感染的重要病原菌之一。因此,建立精准、高效的鲍曼不动杆菌基因分型技术,是开展其医院内感染流行病学研究和临床防控的重要工具。本文就近年来鲍曼不动杆菌基因分型技术的研究进展进行综述,并分析比较多种基因分型技术的原理、优点、局限性及应用范围。     

鲍曼不动杆菌碳青霉烯酶基因分布与 耐药相关性研究

目的研究鲍曼不动杆菌碳青霉烯酶基因的分布与其耐药的相关性。方法收集2015年1月至2017年3月瑞安市两家市级医院的100株耐碳青霉烯类抗生素鲍曼不动杆菌,应用PCR技术检测碳青霉烯酶的相关基因,应用ERIC-PCR法对筛选结果阳性菌株进行DNA同源性分析。结果 100株耐碳青霉烯类抗生素鲍曼不动杆菌中,有50株携带OXA-51基因,26株携带OXA-23基因,同时携带OXA-51和OXA-23基因的有10株,未检出其他碳青霉烯酶基因。对筛选出的58株鲍曼不动杆菌进行同源性分析,得出的DNA指纹条带数为7条,其大小为200~2 000bp。根据片段数目和大小,分为A、B、C、D、E共5种基因型,分别有38、32、21、5、4个克隆株。结论本地区鲍曼不动杆菌对碳青霉烯类药物耐药的机制主要为携带OXA-23基因,克隆传播是主要的传播途径。     

呼吸机相关性肺炎的痰培养细菌分布和细菌耐药性分析

目的:探讨呼吸机相关性肺炎痰培养的泛耐药鲍曼不动杆菌的分布情况,分析泛耐药鲍曼不动杆菌的耐药性与危险因素。方法:选择2016年1月到2016年12月在我院进行机械通气的患者3826例作为研究对象,其中发生泛耐药鲍曼不动杆菌呼吸机相关性肺炎98例为观察组,同期按照2:1的比例选择非泛耐药鲍曼不动杆菌呼吸机相关性肺炎患者49例作为对照组,两组都进行细菌耐药性分析,同时调查患者的临床资料,分析呼吸机相关性肺炎患者中泛耐药鲍曼不动杆菌感染发生的危险因素。结果:观察组对于头孢噻肟、哌拉西林、亚胺培南、庆大霉素、左氧氟沙星、四环素、头孢他啶都高度耐药;除哌拉西林、多粘菌素外,对照组对抗菌药物的耐药率均明显低于观察组(P0.05)。单因素分析结果显示合并糖尿病、机械通气时间、APACHEⅡ评分、GCS评分、深静脉置管等因素与呼吸机相关性肺炎患者中泛耐药鲍曼不动杆菌感染显著相关(P0.05);非条件Logistic回归分析结果显示糖尿病、机械通气时间、APACHEⅡ评分、GCS评分导致呼吸机相关性肺炎患者中泛耐药鲍曼不动杆菌感染的独立危险因素(P0.05)。结论:呼吸机相关性肺炎患者中泛耐药鲍曼不动杆菌感染比较常见,对绝大多数抗菌药物有耐药性,糖尿病、机械通气时间、APACHEⅡ评分、GCS评分为主要的危险因素。     

鲍曼不动杆菌对碳青霉烯类抗生素的耐药性分析

目的了解鲍曼不动杆菌的耐药情况,并检测耐碳青霉烯类鲍曼不动杆菌的耐药基因,为指导临床合理用药、控制院内感染提供依据。方法利用K-B法检测45株鲍曼不动杆菌临床分离株的耐药情况,通过改良Hodge试验、Carba NP试验和EDTA协同试验对多重耐药鲍曼不动杆菌的碳青霉烯酶进行表型检测,并采用PCR技术检测鲍曼不动杆菌携带OXA-23和NDM-1型耐药基因的情况。结果 45株鲍曼不动杆菌临床分离株中共筛出42株多重耐药菌株;利用改良Hodge试验和Carba NP试验检出36株碳青霉烯酶阳性菌株;采用PCR扩增出OXA-23,未扩增出NDM-1。结论鲍曼不动杆菌耐药情况严重,且耐药基因OXA-23携带率高,治疗时应根据药敏试验结果合理用药。     

醋酸钙-鲍曼不动杆菌复合体临床分离株多重PCR分型和感染特征分析

目的在临床微生物实验室建立醋酸钙-鲍曼不动杆菌复合体分型的方法,对相应菌株的药敏情况和临床特征进行分析,为临床准确诊断和有效治疗提供参考依据。方法收集苏州大学附属第一医院2015年10月至2016年1月临床分离的45株醋酸钙-鲍曼不动杆菌复合体菌株,用多重PCR法进行基因分型,用K-B法进行药敏试验,并采用SPSS 17.0软件进行统计分析。结果 45株醋酸钙-鲍曼不动杆菌复合体用多重PCR法鉴定为鲍曼不动杆菌38株,基因3型5株,基因13TU 2株,未鉴定出醋酸钙不动杆菌。标本来源以痰最多(35例),其次为血液标本(6例),脑脊液(2例)。科室分布在神经外科(11例)和ICU(10例)最多,其次是重症医学科(7例)和心胸大外科(6例)。年龄分布以41~60岁(17例)以及61~80岁(15例)两个年龄段最多;性别分布以男性较多(31例),女性较少(14例),而且各个年龄段男性均多于女性。在8种临床常用药物中,对头孢吡肟、哌拉西林、哌拉西林/他唑巴坦、环丙沙星和亚胺培南的耐药率均超过了70.0%,其中哌拉西林的耐药率最高(84.4%),阿米卡星的敏感率最高(51.1%)。结论多重PCR技术能对醋酸钙-鲍曼不动杆菌复合体进行快速基因分型,它成本低、操作简便,适合在临床微生物实验室推广。目前鲍曼不动杆菌引起的感染形势严峻,患者以中老年患者、男性、呼吸道感染、神经外科和ICU科室居多。鲍曼不动杆菌感染大多呈多重耐药甚至泛耐药。推荐临床通过积极治疗原发病,医护人员做好手卫生,加强消毒隔离,根据药敏结果合理选择抗生素等方法尽量减少和延缓耐药菌株的出现。     

重症监护病房鲍曼不动杆菌医院感染的调查分析

通过对重症监护病房内鲍曼不动杆菌医院感染的临床特征和耐药性调查分析,为临床更好地预防和治疗该细菌所引起的感染提供参考。对我院2009年1月至2011年12月重症监护病房鲍曼不动杆菌医院感染的107例患者进行回顾性调查。94例患者有严重的基础疾病,与感染相关的因素还包括侵入性操作、深静脉置管、环境污染及长期广谱抗菌药物的使用;药敏结果显示鲍曼不动杆菌几乎均为多重耐药,对碳青霉烯类抗菌药物的耐药率逐年升高,2011年为89.5%。缩短住院时间、加强病区环境和空气监控、尽量减少侵入性操作和合理使用抗生素、规范医疗护理操作、避免交叉感染是减少鲍曼不动杆菌感染发生的重要措施。     

鲍曼不动杆菌耐消毒剂基因检测

目的 了解深圳市人医院鲍曼不动杆菌抗季铵盐类消毒剂基因的检出率及基因型特点.方法 收集深圳市人民医院临床标本中分离鲍曼不动杆菌67株,PCR检测分离株的qacA/B、qacE△1、qacC、qacG和qacJ 5种抗季铵盐类消毒剂基因.结果 67株鲍曼不动杆菌中qacE△l基因阳性42株(62.6％),qacA/B与qacG基因各有一菌株阳性,未检测出qacC或qacJ基因阳性菌株.结论 深圳市人医院鲍曼不动杆菌中抗季铵盐类消毒剂基因检出率较高,主要为qacE△1型.     

鲍曼不动杆菌感染的呼吸机相关肺炎20例

目的 了解我院NICU内鲍曼氏不动杆菌感染呼吸机相关肺炎的情况,探讨有效预防和控制的该类感染的措施。方法 收集我院NICU内2006.1-2007.2之间发生呼吸相关肺炎病通过细菌培养确定为鲍曼氏不动杆菌感染的患儿的临床资料以及该菌的药敏试验结果进行分析。结果 鲍曼氏不动杆菌是呼吸机相关肺炎的主要致病菌之一,其流行情况复杂,并且出现了耐碳青酶烯类的菌株感染,可造成严重的不良后果。结论 预防该菌在NICU内导致感染需要引起临床工作者更多的重视,加强对其定植情况的监测是预防其感染和流行的重要措施,对该菌开展及分子流行病学的深入研究将有助于指导NICU内NI防治。     

Factors associated to duration of hepatitis a outbreaks: implications for control

Even though hepatitis A mass vaccination effectiveness is high, outbreaks continue to occur. The aim of this study was to investigate the association between duration and characteristics of hepatitis A outbreaks. Hepatitis A (HA) outbreaks reported between 1991 and 2007 were studied. An outbreak was defined as ≥2 epidemiologically-linked cases with ≥1 case laboratory-confirmed by detection of HA immunoglobulin M (IgM) antibodies. Relationships between explanatory variables and outbreak duration were assessed by logistic regression. During the study period, 268 outbreaks (rate 2.45 per million persons-year) and 1396 cases (rate 1.28 per 10⁵ persons-year) were reported. Factors associated with shorter duration were time to intervention (OR = 0.96; 95% CI: 0.94–0.98) and school setting (OR = 0.39; 95% CI: 0.16–0.92). In person-to-person transmission outbreaks only time to intervention was associated with shorter outbreak duration (OR = 0.96; 95% CI: 0.95–0.98). The only variables associated with shorter outbreak duration were early administration of IG or vaccine and a school setting. Timely reporting HA outbreaks was associated with outbreak duration. Making confirmed HA infections statutory reportable for clinical laboratories could diminish outbreak duration.     

Molecular investigation of enteroaggregative, shiga toxin-producing E. coli O104:H4 isolated in Poland during the recent international outbreak--characteristic of epidemic clone

Since early May 2011 a large food-borne outbreak caused by E. coli O104:H4 affected Germany then spread over 13 European countries, U.S.A. and Canada. The outbreak strain was found to possess an unusual combination of enteroaggregative E. coli pathotype with StxII. In this report we described the molecular investigation of epidemic clone in Poland during the international outbreak. We confirmed three cases of E. coli O104:H4 infections. The molecular characteristics of the Polish E. coli O104:H4 isolates including virulence profile, antimicrobial resistance, PFGE and plasmids profiles were corresponded with Germany outbreak strains.     

呼吸科住院患者耐碳青霉烯鲍曼不动杆菌抗菌药物敏感性及其分子特征

目的调查深圳市人民医院呼吸科住院患者耐碳青霉烯鲍曼不动杆菌（CRAB）的抗菌药物敏感性和耐药分子机制,以及克隆流行情况。方法收集2010年深圳市人民医院呼吸科住院患者临床分离CRAB29株,琼脂稀释法测定亚胺培南等15种抗菌药对CRAB的最低抑菌浓度（MIC）,PCR和DNA测序分析CRAB碳青霉烯酶基因型,脉冲场凝胶电泳（PFGE）分析菌株同源性。结果多粘菌素B对29株CRAB抗菌活性最强,敏感性100％,MIC50／MIC90为1／1μg/mL,其次米诺环素,敏感性96．6％,MIC50／MIC90为4／4μg/mL,替加环素中介率高达96．6％,MIC50／MIC90为4／4μg/mL。96．6％（28／29）CRAB携带ISAba1—blaOXA-23-like,对亚胺培南和美罗培南高度耐药,亚胺培南和美罗培南的MIC集中分布在32—64μg／mL;1株携带ISAba1—blaOXA-51-like CRAB,对亚胺培南和美罗培南中度耐药,亚胺培南和美罗培南的MIC分别为4μg/mL和8μg/mL。29株CRAB未发现blaOXA-24-like、blaOXA-143-like、金属酶基因及KPC酶基因。29株CRAB经PFGE分型共分2型,以A型28株（96．6％）为主要流行克隆,均携带ISAba1-blaOXA-23-like。结论2010年我院呼吸科临床分离CRAB主要携带ISAba1—blaOXA-23-like基因,并以克隆播散流行。     

福州地区碳青霉烯类耐药鲍曼不动杆菌碳青霉烯酶基因型研究

目的探讨福州地区碳青霉烯类耐药鲍曼不动杆菌(CRAB)碳青霉烯酶基因型的流行情况。方法收集多家医院临床标本中分离得到的107株CRAB。应用K-B纸片扩散法进行药物敏感试验。采用PCR法检测7种碳青霉烯酶基因,包括OXA-23、OXA-24、OXA-51、OXA-58、IMP-1、IMP-4和VIM-2。结果 107株CRAB对除多粘菌素B、米诺环素外的其他所有常见的抗生素均为耐药。碳青霉烯酶基因OXA-51、OXA-23的检出率分别为100.0%(107/107)和87.9%(94/107)。其他OXA-24、OXA-58、IMP-1、IMP-4和VIM-2基因均未检出。结论福州地区临床分离的CRAB耐药现象严重;表达OXA-23基因是CRAB对碳青霉烯类药物耐药的重要机制之一。     

Economic impact of a nationwide outbreak of salmonellosis: cost-benefit of early intervention.

The recognition and investigation of an outbreak of food poisoning in 1982 due to chocolate contaminated with Salmonella napoli enabled the food that carried the salmonella to be identified and four fifths of the implicated consignment of chocolate to be withdrawn. The economic benefits of prompt intervention in the outbreak have been assessed. The cost of the outbreak was over 0.5 pounds m. It is estimated that five deaths were prevented by the intervention and that 185 admissions to hospital and 29,000 cases of S napoli enteritis were avoided. This successful investigation yielded a 3.5-fold rate of return to the public sector and a 23.3-fold return to society on an investment in public health surveillance. A methodology is described that can be used to estimate the benefits of early intervention in outbreaks of foodborne illness and topics for further research are suggested. It is concluded that public health authorities and industry have much to gain by collaborating in the research into the design of cost effective programmes to prevent foodborne infections.     

Outbreak of acute respiratory disease caused by human adenovirus type 7 in a military training camp in Shaanxi,China

Outbreaks of ARD associated with HAdV have been reported in military populations in many countries. Here, we report an ARD outbreak caused by HAdV‐7 in a military training camp in Shaanxi Province, China, from February to March of 2012. Epidemic data and samples from the patients were collected, and viral nucleotides from samples and viral isolations were detected and sequenced. IgG and IgA antibodies against HAdV, and the neutralization antibodies against the viral strain isolated in this outbreak, were detected. Epidemiological study showed that all personnel affected were males with an average age of 19.1 years. Two peaks appeared on the epicurve and there was an 8‐day interval between peaks. Laboratory results of viral nucleotide detection carried out with clinical specimens were positive for HAdV (83.33%, 15/18). Further study through serum antibody assay, virus isolation and phylogenetic analysis showed that HAdV‐7 was the etiological agent responsible for the outbreak. IgA antibody began to appear on the 4th day after the onset and showed 100% positivity on the 8th day. The virus strain in the present outbreak was highly similar to the virus isolated in Hanzhong Shaanxi in 2009. We conclude that HAdV‐7 was the pathogen corresponding to the outbreak, and this is the first report of an ARD outbreak caused by HAdV‐7 in military persons in China. Vaccine development, as well as enhanced epidemiological and virological surveillance of HAdV infections in China should be emphasized.     

Community Involvement in Dengue Outbreak Control: An Integrated Rigorous Intervention Strategy

BackgroundAn explosive outbreak of dengue fever occurred in Guangdong Province, China in 2014. A community-based integrated intervention was applied to control this outbreak in the capital city Guangzhou, where dengue epidemic was mainly caused by imported cases.ConclusionsThis study suggests that an integrated dengue intervention program has significant effects to control a dengue outbreak in areas where dengue epidemic was mainly caused by imported dengue cases.     

Evaluation of Inapparent Dengue Infections During an Outbreak in Southern China

Few studies evaluating inapparent dengue virus (DENV) infections have been conducted in China. In 2013, a large outbreak of DENV occurred in the city of Zhongshan, located in Southern China, which provided an opportunity to assess the clinical spectrum of disease. During the outbreak, an investigation of 887 index case contacts was conducted to evaluate inapparent and symptomatic DENV infections. Post-outbreak, an additional 815 subjects from 4 towns with, and 350 subjects from 2 towns without reported autochthonous DENV transmission, as determined by clinical diagnosis, were evaluated for serological evidence of dengue IgG antibodies. Between July and November 2013, there were 19 imported and 809 autochthonous dengue cases reported in Zhongshan. Of 887 case contacts enrolled during the outbreak, 13 (1.5%) exhibited symptomatic DENV infection, while 28 (3.2%) were inapparent. The overall I:S ratio was 2.2:1 (95% CI: 1.1-4.2:1). Post-outbreak serological data showed that the proportion of DENV IgG antibody detection from the 4 towns with and the 2 towns without reported DENV transmission was 2.7% (95% CI: 1.6%-3.8%) and 0.6% (95% CI: 0-1.4%), respectively. The I:S ratio in the 3 towns where clinical dengue cases were predominately typed as DENV-1 was 11.0:1 (95% CI: 3.7-∞:1). The ratio in the town where DENV-3 was predominately typed was 1.0:1 (95% CI: 0.5-∞:1). In this cross-sectional study, data suggests a high I:S ratio during a documented outbreak in Zhongshan, Southern China. These results have important implications for dengue control, implying that inapparent cases might influence DENV transmission more than previously thought.     

Follow-up study of type C influenza outbreak in a children's home

A follow-up study of type C influenza in a children's home was made where the first outbreak of type C influenza occurred in March, 1981. During the survey period of 2 years, 2 additional outbreaks occurred in April and October, 1982 and 4 cases of the secondary and 2 cases of the tertiary infections were serologically confirmed. All of the children exposed to the outbreaks, except 2 particular cases who were suffering from German measles, showed similar mild respiratory symptoms characterized by fever and long-lasting nasal discharge, irrespective of primary, secondary, and tertiary infections. No case of inapparent infection was observed. Incubation period was estimated to be not longer than 5 days and the period of virus shedding, to be longer than 22 days. Antibody response in the sera of patients to type C influenza virus was equally good after every infection, although it was not efficient to prevent the succeeding infection. Factors involved in the repeated infections of type C influenza were discussed.     

Persistence of carbapenem-resistant Acinetobacter baumannii strains in an Italian intensive care unit during a forty-six month study period

The aims of this study were to analyze carbapenem-resistance Acinetobacter baumannii isolates (CRAB) and their molecular epidemiology in an ICU of Southern Italy. Clinical outcomes and therapeutic management of patients are also described. The study was performed from January 2007 to October 2010. The presence of carbapenemases was determined by PCR. Strains were typed by PFGE. All A. baumannii isolates were carbapenem-resistant with imipenem MIC≥16 μg/mL. Molecular characterization showed the occurrence of a predominant clone. The most frequent infection by CRAB was ventilator-associated pneumonia; colistin was the drug of choice for this infection. The therapy was safe in all cases except in one where therapy was suspended due to the onset of acute renal failure. We documented the presence of CRAB in this ICU, besides the occurrence of a predominant clone, over all the study period. Despite the infection control procedures used, intra-facility A. baumannii transmission is evident as well as the significant capacity for long-term survival in the hospital environment.