2013—2022年河北省单核细胞增生李斯特菌的临床分布及耐药性

目的 回顾性分析2013—2022年河北省细菌耐药监测网75所医院单核细胞增生李斯特菌的分布及耐药性,为临床治疗及合理使用抗菌药物提供依据。 方法 应用WHONET软件对2013年1月—2022年6月河北省75所医院临床分离的单核细胞增生李斯特菌的标本来源、科室分布及耐药性进行分析。 结果 2013—2022年河北省共检出187株单核细胞增生李斯特菌,分离标本主要为血(129株,69.0%)、脑脊液(20株,10.7%)、胃液(14株,7.5%)及其他(18株,9.6%);70株(37.4%)分离自男性,117株(62.6%)分离自女性;新生儿科(42株,22.5%)和妇产科(41株,21.9%)为最常见的来源科室;年龄分组上,青年人(74株,39.6%)最多,其次为新生儿(39株,20.9%)。该菌对青霉素、氨苄西林、美罗培南、复方磺胺甲唑和红霉素的敏感率分别为97.8%、98.6%、98.0%、98.4%和96.3%。 结论 2013—2022年河北省临床分离的单核细胞增生李斯特菌大多来源于血标本,感染人群以青年和新生儿为主,该菌已出现一线治疗药物的非敏感株,需持续关注。     

单核细胞增生李斯特菌感染的临床特征

目的 分析单核细胞增生李斯特菌感染患者的临床特征及治疗情况。方法 回顾性收集2016年1月-2018年12月某院单核细胞增生李斯特菌感染患者的临床资料,分析患者的临床特征、实验室检查、抗菌药物使用方案及预后等。结果 15例单核细胞增生李斯特菌感染患者,其中非妊娠成年人大多为65岁以上且有基础疾病的老年人;14例败血症患者（其中1例合并化脓性脑膜炎）,1例化脓性脑膜炎患者。败血症成年患者均有发热,新生儿仅1例有发热;2例化脓性脑膜炎患者除发热外均有头痛、呕吐等神经系统症状。15例患者中大部分患者白细胞、C反应蛋白（CRP）、降钙素原（PCT）均升高,2例化脓性脑膜炎患者脑脊液检查明显异常。治疗上予以单用青霉素或美罗培南,或者两种药物联合使用,14例患者好转,1例患者病情加重。结论 单核细胞增生李斯特菌主要引起新生儿、孕妇、老年人、免疫力低下人群感染,感染类型常见血流感染或化脓性脑膜炎,青霉素、氨苄西林、美罗培南和复方磺胺甲口恶唑可用来经验性治疗单核细胞增生李斯特菌感染。     

Outbreak of Listeria monocytogenes in an oncology unit associated with sandwiches consumed in hospital

In May 2003, two adult patients in an oncology unit were diagnosed with listeriosis, and sandwiches consumed in the hospital were identified as a common risk factor. Both patients were infected by the same strain of Listeria monocytogenes. Sandwiches collected from the hospital and external sandwich producer, as well as sites within the manufacturing environment, were contaminated by the same strain of L. monocytogenes. Sandwiches consumed in other hospitals have been associated with small clusters of listeriosis patients in the UK. This report describes the investigations following diagnosis of the two infections, and highlights a more general problem with sandwiches sold in hospitals.     

Bacteriological safety of cook-chill food at the Royal Free Hospital, with particular reference to Listeria

Cook-chill food prepared by the Catering Department of the Royal Free Hospital was examined over an 8-month period commencing October 1989. Total aerobic viable counts (TAVCs) were performed on 200 food specimens which were also examined for Listeria using selective enrichment culture. Ten of 200 food samples tested had TAVCs > 10⁵ colony forming units (cfu) g⁻¹, and nine of these were from non-vegetarian (meat) dishes. Although most of the food prepared by cook-chill had microbial loads within the limits recommended by current Department of Health guidelines (i.e. <10⁵ cfu g⁻¹), our findings for the non-vegetarian dishes suggest that extra caution is required when preparing such food. Listeria were not isolated from any food sample. In a survey of listeria faecal carriage, Listeria monocytogenes was isolated from only two of 100 faeces specimens obtained from patients.     

Human impact on genetic diversity of Toxoplasma gondii: Example of the anthropized environment from French Guiana

In French Guiana, severe cases of toxoplasmosis in immunocompetent patients are associated with atypical strains of Toxoplasma gondii linked to a wild neotropical rainforest cycle and a higher genetic diversity than usually observed for T. gondii isolates from anthropized environment. This raises the question of the impact of anthropization of the natural environment, on genetic diversity and on the population structure of T. gondii. However, few data are available on strains circulating in the anthropized areas from French Guiana. Seropositive animals originating mainly from anthropized sub-urban areas and punctually from wild environment in French Guiana were analyzed for T. gondii isolation and genotyping. Thirty-three strains were obtained by bioassay in mice and compared with 18 previously reported isolates chiefly originating from the Amazon rainforest. The genotyping analysis performed with 15 microsatellite markers located on 12 different chromosomes revealed a lower genetic diversity in the anthropized environment. Results were analyzed in terms of population structure by clustering methods, Neighbor-joining trees reconstruction based on genetic distances, F_ST, Mantel's tests and linkage disequilibrium. They clearly showed a genetic differentiation between strains associated to the anthropized environment and those associated to the wild, but with some inbreeding between them. The majority of strains from the anthropized environment were clustered into additional lineages of T. gondii that are common in the Caribbean. In conclusion the two environmental populations “wild” and “anthropized” were genetically well differentiated. The anthropization of the environment seems to be accompanied with a decreased diversity of T. gondii associated with a greater structure of the populations. We detected potential interpenetration and genetic exchanges between these two environmental populations. As a higher pathogenicity in human of “wild” genotypes has been described, the interpenetration of both environments leads to hybridization between strains that may be at risk for human health.     

Recombinant attenuated Listeria monocytogenes vaccine expressing Francisella tularensis IglC induces protection in mice against aerosolized Type A F. tularensis

Fransicella tularensis, the causative agent of tularemia, is in the top category (Category A) of potential agents of bioterrorism. To develop a safer vaccine against aerosolized F. tularensis, we have employed an attenuated Listeria monocytogenes, which shares with F. tularensis an intracellular and extraphagosomal lifestyle, as a delivery vehicle for F. tularensis antigens. We constructed recombinant L. monocytogenes (rLm) vaccines stably expressing seven F. tularensis proteins including IglC (rLm/iglC), and tested their immunogenicity and protective efficacy against lethal F. tularensis challenge in mice. Mice immunized intradermally with rLm/iglC developed significant cellular immune responses to F. tularensis IglC as evidenced by lymphocyte proliferation and CD4+ and CD8+ T-cell intracellular expression of interferon gamma. Moreover, mice immunized with rLm/iglC were protected against lethal challenge with F. tularensis LVS administered by the intranasal route, a route chosen to mimic airborne infection, and, most importantly, against aerosol challenge with the highly virulent Type A F. tularensis SchuS4 strain.     

乳腺炎奶牛双重感染抗热分枝杆菌和象分枝杆菌的鉴定及药敏试验研究

目的 对疑似分枝杆菌感染乳腺炎奶牛进行病原及药敏谱调查。方法 采集1头患乳腺炎奶牛的牛奶,采用4% NaOH预处理,接种于L-J培养基分离培养。阳性培养物利用抗酸染色和多位点PCR方法进行初步鉴定,采用16S rRNA、hsp65、ITS,和SodA基因的多位点序列分析进行种的鉴定,利用Alamar blue显色法对分离菌株进行27种药物的药敏试验。结果 从1头患乳腺炎奶牛的牛奶中同时分离获得2株抗酸染色阳性培养物,经PCR鉴定为非结核分枝杆菌,多位点序列分析鉴定为抗热分枝杆菌和象分枝杆菌。药敏试验表明这2株菌对利福平和异烟肼等大多数抗结核药物耐药,但对阿米卡星、莫西沙星、左氧氟沙星、乙胺丁醇、链霉素、妥布霉素、环丙沙星和利奈唑胺等敏感。结论 乳腺炎奶牛中分离了抗热分枝杆菌和象分枝杆菌,有其独特的药敏谱特征,为其感染防治提供了科学依据。     

Dynamics of Aeromonas species isolated from wastewater treatment system

Aeromonas are widely distributed in the aquatic environment, and are considered to be emerging organisms that can produce a series of virulence factors. The present study was carried out in a sanitary sewage stabilization pond treatment system, located in Lins, State of São Paulo, Brazil. Most probable number was applied for estimation of the genus Aeromonas. Colony isolation was carried out on blood agar ampicillin and confirmed by biochemical characterization. Aeromonas species were isolated in 72.4% of influent samples, and in 55.2 and 48.3% of effluent from anaerobic and facultative lagoons, respectively. Thirteen Aeromonas species were isolated, representing most of the recognized species of these organisms. Even though it was possible to observe a tendency of decrease, total elimination of these organisms from the studied system was not achieved. Understanding of the pathogenic organism's dynamics in wastewater treatment systems with a reuse potential is especially important because of the risk it represents.     

Cyst morphology and sequence analysis of the small subunit rDNA and ef1α identifies a novel Giardia genotype in a quenda (Isoodon obesulus) from Western Australia

Sequence analysis of the small subunit ribosomal DNA (SSU-rDNA) and elongation factor 1 alpha (ef1 alpha) was performed on Giardia cysts isolated from faeces collected from a quenda (Isoodon obesulus) in the southwest of Western Australia. The SSU-rDNA and ef1 alpha were sequenced in their entirety and correspondingly aligned with the published sequence information of other known species and genotypes of Giardia. Phylogenetic analysis of the SSU-rDNA and ef1 alpha sequences identified the quenda isolate as a novel genotype of Giardia not previously reported. We believe that this quenda Giardia isolate constitutes a distinct species, which may be endemic within the Australian native fauna.     

Fine-tuning the safety and immunogenicity of Listeria monocytogenes-based neonatal vaccine platforms

We have developed virulence-attenuated strains of Listeria monocytogenes (Lm) that can be used as safe yet effective vaccine carriers for neonatal vaccination. Here we compare the vaccine efficacy of Lm based vaccine carrier candidates after only a single immunization in murine neonates and adults: Lm Δ(trpS actA) based strains that express and secrete multiple copies of the model antigen ovalbumin (OVA) either under the control of a phagosomal (P_hly) or cytosolic (P_actA)-driven listerial promoter. While both strains induced high levels of antigen-specific primary and secondary CD8 and CD4 T cell responses, both neonatal and adult mice immunized with the phagosomal driven strain were significantly better protected against wildtype Lm challenge as compared to the naïve control group than mice immunized with the cytosolic driven strains. Interestingly, only neonatal mice immunized with the phagosomal driven strains generated high IgG antibody responses against OVA. Our phagosomal driven Lm-based vaccine platform presents the broadest (cellular & humoral response) and most efficient (highly protective) vaccine platform for neonatal vaccination yet described.     

肺炎克雷伯菌、类肺炎克雷伯菌和变栖克雷伯菌的研究进展

肺炎克雷伯菌临床分离株是一种有荚膜的革兰阴性粗短杆菌,是临床上重要的机会致病菌。肺炎克雷伯菌临床分离株基因间存在差异,依据系统发育树可分为肺炎克雷伯菌(Klebsiella pneumoniae, KpⅠ)、类肺炎克雷伯菌(Klebsiella quasipneumoniae, KpⅡ)和变栖克雷伯菌(Klebsiella variicola, KpⅢ),三者生态分布、基因型、耐药性、毒力特征以及致病性存在显著差异,为感染性疾病精准治疗带来新的挑战。本文对KpⅠ、KpⅡ、KpⅢ的鉴定、流行特点及致病特点的最新研究进展进行综述。     

Identification and biotyping of Acinetobacter spp. isolated in Chilean hospitals

Two hundred and eighty-one isolates of Acinetobacter spp. obtained from clinical specimens in hospitals from five Chilean cities were identified to species level and biotyped. Respiratory tract and wound secretions were the main sources of the isolates. Acinetobacter baumannii was the most frequent species (96·8%), followed by Acinetobacter genospecies 3 (2·8%). Twelve different biotypes of A. baumannii strains were found of which biotypes 9, 8 and 6 were the most frequent. Isolates of other biotypes were rare. These results differ from most other Latin American and European countries.     

血液分离耐碳青霉烯类肺炎克雷伯菌耐药性及相关危险因素

目的 探讨血液分离耐碳青霉烯类肺炎克雷伯菌(CRKP)的耐药性及患者感染的相关危险因素。 方法 回顾性分析2018年1月—2021年12月在某院住院并从血液中分离出肺炎克雷伯菌(KP)的383例KP感染患者的临床资料, 依据耐药情况分为CRKP组(114例)和non-CRKP组(269例), 根据预后情况将114例CRKP组患者分为两个亚组: 死亡组(30例)和存活组(84例), 分别比较两组患者的一般资料、基础疾病、抗菌药物使用情况和感染结局等, 并分析患者感染及感染后死亡的危险因素。 结果 KP对替加环素和复方磺胺甲口恶唑的耐药率呈上升趋势, 差异均有统计学意义(均P=0.008)。CRKP组对阿米卡星、氨曲南、复方磺胺甲口恶唑、环丙沙星、头孢吡肟、头孢哌酮/舒巴坦、哌拉西林/他唑巴坦、替加环素、头孢他啶、妥布霉素和左氧氟沙星的耐药率及患者住院病死率均高于non-CRKP组, 差异均有统计学意义(均P＜0.05)。感染前患有急性胰腺炎(OR=16.564, P＜0.001)、低蛋白血症(OR=8.588, P＜0.001)、感染前入住重症监护病房(OR=2.733, P=0.017)、输血(OR=3.968, P=0.001)、支气管镜检查(OR=5.194, P=0.014)、感染前30 d内手术(OR=2.603, P=0.010)和接受碳青霉烯类药物治疗(OR=2.663, P=0.011)是发生CRKP血流感染(BSI)的独立危险因素。感染前患有心功能不全(OR=11.094, P=0.001)、合并肺部感染(OR=20.801, P=0.010)、感染性休克(OR=9.783, P=0.002)、意识障碍(OR=11.648, P=0.001)和接受糖皮质激素治疗(OR=5.333, P=0.018)是BSI CRKP患者死亡的独立危险因素。 结论 BSI分离的KP对替加环素和复方磺胺甲口恶唑的耐药率呈上升趋势, 基础疾病、侵入性操作和碳青霉烯类药物治疗与CRKP BSI密切相关, 心功能不全、肺部感染、感染性休克、意识障碍和糖皮质激素治疗可导致BSI CRKP患者死亡。     

中国幽门螺杆菌基因组多样性与种群结构分析

目的 了解中国幽门螺杆菌（Helicobacter pylori,HP）基因组特征及种群结构。方法 利用中国不同地域不同疾病分离的10株HP的基因组序列,并整合公共数据库中其他地域的HP基因组数据,通过比较基因组和生物信息学方法分析中国HP的基因组与种群结构特征。结果 中国HP核心基因为1 203个。菌株特异基因为19～32个,这些基因可能与中国HP在不同地域、不同疾病宿主中的适应性进化有关。基因组变异较大区域主要集中在编码限制修饰系统的基因和编码四型分泌系统的基因。基于核心基因组单核苷酸多态性（SNP）的种群分析确定中国菌株均属于hpEastAsia群,hspEAsia亚群,且不同地域菌株具有地域聚集性特点。在3株中国HP基因组序列中发现了前噬菌体序列,携带噬菌体组装所需的必要元件。结论 基于核心基因组SNP分析中国菌株均属于hpEastAsia群,hspEAsia亚群,且具有地域聚集性。为深入挖掘中国不同地域不同疾病相关HP的遗传特征及研究噬菌体在HP进化与致病中的作用奠定了基础。     

上海嘉定区某医院2018—2022年环境中金黄色葡萄球菌的分布及其耐药性

目的 了解上海市嘉定区某医院环境中金黄色葡萄球菌(SA)的污染状况及耐药性,探讨环境菌株中耐甲氧西林金黄色葡萄球菌(MRSA)检出情况及耐药性特点。 方法 采集该医院环境标本并分离鉴定SA,采用肉汤稀释法对分离的SA进行15种常见抗菌药物耐药性检测,并检测菌株mecA基因。 结果 936份医院环境标本中,60份标本检出SA,检出率为6.41%,SA中MRSA的检出率为25.00%。综合重症监护病房(ICU)、呼吸内科SA的检出率分别为7.35%、5.94%,MRSA的检出率分别为3.51%、0.64%。医院环境中鼠标键盘SA的检出率最高(17.14%),其次是患者的病号服、枕头被褥和床头柜(均为16.67%)。环境标本中肥皂(盒)、洗手(消毒)瓶的MRSA检出率最高,分别为7.69%、6.25%。医院环境标本中的SA对达托霉素、利奈唑胺、呋喃妥因、利福平、复方磺胺甲唑、替考拉宁、万古霉素7种抗菌药物均敏感,MRSA对其余8种抗菌药物的耐药率均高于甲氧西林敏感金黄色葡萄球菌(MSSA)。 结论 该医院综合ICU环境检出的SA中MRSA的占比高于呼吸内科,环境标本中高MRSA检出率和高SA检出率的标本不一致,MRSA的耐药率高于MSSA,需加强医院,特别是ICU中SA及MRSA的消毒与控制,避免SA耐药性升高。     

青海省结核分枝杆菌临床分离株可变数目串联重复序列基因多态性研究

目的 初步了解青海省结核分枝杆菌临床分离株基因多态性和基因分型特征。方法 2009-2012年收集青海省疾病预防控制中心分离的结核分枝杆菌临床分离株,提取DNA,对15个可变数目串联重复序列(VNTR)位点进行PCR扩增和产物电泳分析,使用BioNumerics软件对菌株进行聚类分析。结果 共检测251株结核分枝杆菌临床分离株的15个VNTR位点,显示这些菌株有明显的基因多态性,15个VNTR位点中Hunter-Gaston指数>0.6的VNTR位点有6个,位点分辨能力最高的是MIRU26,经聚类分析,可分为4个基因群,238个基因型。4个基因群分别占4.9%、91.9%、1.6%和1.6%。结论 青海省流行的结核分枝杆菌菌株存在明显的VNTR基因多态性。     

空肠弯曲菌、结肠弯曲菌检验方法团体标准解读

空肠弯曲菌和结肠弯曲菌是重要的食源性病原菌，是导致人类弯曲菌病的重要菌种。病原菌的培养、鉴定是食品污染以及人和动物感染诊断的“金标准”。中国CDC传染病预防控制所和国家食品安全风险评估中心等单位撰写了《空肠弯曲菌、结肠弯曲菌检验方法（T/CPMA 006－2019）》团体标准。标准以“科学性、规范性、适用性和可行性”为基本原则，提出从不同种类的标本、样品中空肠弯曲菌和结肠弯曲菌的分离培养以及鉴定的方法，用于指导和规范我国不同种类的标本以及样本中两种弯曲菌的检测过程、检测步骤和鉴定方法，提高空肠弯曲菌、结肠弯曲菌的检测水平。     

The occurrence and sources of Campylobacter spp., Salmonella enterica and Escherichia coli O157:H7 in the Salmon River, British Columbia, Canada

In this study, we wished to assess the prevalence and determine the sources of three zoonotic bacterial pathogens (Salmonella, Campylobacter, and Escherichia coli O157:H7) in the Salmon River watershed in southwestern British Columbia. Surface water, sewage, and animal faecal samples were collected from the watershed. Selective bacterial culture and PCR techniques were used to isolate these three pathogens and indicator bacteria from these samples and characterize them. Campylobacter was the most prevalent pathogen in all samples, followed by Salmonella, and E. coli O157:H7. E. coli O157:H7 and Salmonella isolation rates from water, as well as faecal coliform densities correlated positively with precipitation, while Campylobacter isolation rates correlated negatively with precipitation. Analysis of DNA extracted from water samples for the presence of Bacteroides host-species markers, and comparisons of C. jejuni flaA-RFLP types and Salmonella serovars from faecal and water samples provided evidence that human sewage and specific domestic and wild animal species were sources of these pathogens; however, in most cases the source could not be determined or more than one source was possible. The frequent isolation of these zoonotic pathogens in the Salmon River highlights the risks to human health associated with intentional and unintentional consumption of untreated surface waters.     

Changes in aromatic characteristics of Loureiro and Alvarinho wines during maturation

Changes in volatiles during maturation in bottles of monovarietal Vinhos Verdes wines from Loureiro and Alvarinho grape varieties, were followed by chemical and sensory analyses. Young wines and wines matured for 8 and 20 months were studied. The volatiles were determined by gas chromatography–mass spectrometry (GC-MS) after extraction on XAD-2 resin. Straight chain fatty acid ethyl esters and acetates of fusel alcohols decreased quicker for Loureiro wine, while the increase in ethyl esters of branched fatty acids was similar for both varieties. Linalool, Ho-trienol, α-terpineol and β-damascenone could be used to differentiate between each variety. However, linalool decreased to negligible values after 20 months of maturation. β-Damascenone decreased but remained high enough to be useful for differentiating each variety. Sensory analysis indicated a decrease of tropical fruit and tree fruit characters with conservation time for Alvarinho wine, and the opposite for Loureiro; moreover, citrus fruit character decreased in both varieties.