用ELISA法对天津市195名健康人嗜肺军团菌Ⅰ型抗体水平调查

本文报道应用酶联免疫吸附试验(ELISA)检测天津市195名健康人嗜肺军团菌Ⅰ型抗体水平。调查结果表明几何平均滴度为1:81.7,男女平均滴度无显著差别,30~39岁年龄组最高,60岁以上次之,50~59岁抗体水平最低,分别为1:131.6、1:106.4、1:59.1。10/105(5.1%)滴度 ≥ 1:2560,提示健康人群中有军团菌隐性感染存在。     

内蒙古自治区2009年健康人群麻疹抗体水平监测分析

目的了解全区健康人群麻疹抗体水平。方法在11个盟市中随机抽查1893名0～25岁健康人,应用酶联免疫吸附试验检测麻疹IgG抗体。结果检测的1893份血样,麻疹IgG抗体阳性1285份,阳性率为67.88%,阳性率最高为88.00%,最低为53.30%,经x~2检验,地区之间有非常统计学差异。麻疹抗体达到保护水平的有850人,保护率为44.90%,几何平均滴度896,男性阳性率为69.58%,几何平均滴度870;女性阳性率66.33%,几何平均滴度922,经x~2检验,性别间无统计学差异。年龄组间有统计学差异,15～25岁组抗体水平较低,0～2岁组抗体水平最高。结论麻疹抗体水平低的地区,存在麻疹流行和暴发的隐患,要切实做好免疫和强化免疫工作,做好麻疹预防工作。     

宜昌市健康人群5种（14型）军团菌感染情况的调查

本文报告了作者于1988年4～10月用MAT法对宜昌市不同职业的健康人群802人检测Lp1—10、Lb、Lm、Lj、Lf军团菌感染的情况。首次证实该市存在5种(14型)军团菌的隐性感染,其主要菌型为Lf(占51.50％).Lj(50.50％),其次为Lb(占25.69％)和Lp6(22.19％),其它各型较低。不同职业人群中,以街道清洁工和下水道修建工各型抗体阳性率最高,饮食服务业最低。不同年龄、性别的MA抗体阳性分布有明显差异,同时对军团菌抗体正常滴度上限作了比较和讨论,提出了14个型军团菌MA抗体的阳性的参考基线值。     

铜川市流行性乙型脑炎发病特征分析

目的了解铜川市乙脑发病特征及人群抗体水平,为有效防控乙脑提供科学依据。方法采用描述流行病学方法,对铜川市乙脑病例进行统计分析,并在铜川市宜君县随机抽取健康人群采集静脉血检测乙脑中和抗体。结果铜川市1960-2012年共报告乙脑病例649例,死亡59例,年均发病率为2.07/10万,死亡率为0.19/10万,病死率为9.09%。发病呈明显的季节特点,近年来职业分布上以农民、民工为多,15岁以上人群病例占总病例数的93.10%,年龄别发病率以60岁以上人群最高;共采集健康人群血样216对,乙脑流行季节前,健康人群中和抗体阳性率24.07%,抗体几何平均滴度(GMT)1∶3.04;流行季节后,健康人群乙脑中和抗体阳性率为26.39%,抗体几何平均滴度(GMT)1∶3.29,流行季节前后中和抗体阳性率和抗体几何平均滴度差异均无统计学意义。结论乙脑疫苗接种是铜川市预防乙脑最有效的途径,铜川市健康人群乙脑抗体水平主要受疫苗接种影响。在做好适龄儿童免疫接种的同时,对成人也应开展乙脑疫苗强化免疫,建立整个人群的免疫屏障。     

2010年扬州市健康人群麻疹免疫水平调查

[目的]了解健康人群麻疹免疫水平,评价麻疹疫苗免疫效果。[方法]2010年9月,在扬州市广陵和维扬2个区,每区分别抽取7个年龄组的健康人群175名进行血清麻疹IgG抗体检测。[结果]检测350人,麻疹IgG抗体阳性率为93.43%,达保护率为76.86%,几何平均滴度为1∶1 777.07。抗体阳性率、达保护率、几何平均滴度均为<1岁组最低,不同年龄的差异有统计学意义(P<0.01);有麻疹疫苗免疫史者抗体阳性率和达保护率高于无免疫史者(P<0.01);不同性别和不同地区健康人群麻疹IgG抗体阳性率、达保护率、几何平均滴度的差异均无统计学意义(P>0.05)。[结论]扬州市健康人群麻疹免疫状况良好。     

公共场所人群军团菌血清流行病学研究

目的:了解公共场所健康人群军团菌抗体水平,探讨军团菌感染与环境的相关性。方法:采用微量凝集试验(MAT)测定血清中嗜肺军团菌1至6型(Lp1、Lp2、Lp3、Lp4、Lp5和Lp6)抗体滴度。结果:公共场所健康人群军团菌血清抗体阳性率达6.01%,抗体滴度在0-1:64之间,以Lp6、Lp3、和Lp2为主要血清型,中央空调冷却水军团菌阳性单位的健康人群的军团菌血清抗体水平明显高于对照组,其抗体阳性率分别为8.94%和3.07%(2χ=6.91,P<0.01)。结论:象山地区公共场所人群军团菌隐性感染抗体水平较高,与中央空调冷却水军团菌污染水平相关。     

公共场所人群嗜肺军团菌血清抗体水平的调查研究

目的:了解温州市部分人群血清嗜肺军团菌的抗体阳性率以及嗜肺军团菌抗体(LP1～10)的分布特点。方法:采用微量凝集试验(MAT)测定就业人员血清中嗜肺军团菌1至10型抗体滴度。结果:1000例人群血清抗嗜肺军团菌抗体阳性89例,总阳性率为8.9%,其中暴露人群血清中嗜肺军团菌感染的阳性率11.6%(58/500),对照人群血清中嗜肺军团菌感染的阳性率6.2%(31/500),阳性率有显著性差异,暴露人群高于对照人群(χ2=8.991,P<0.05)。在阳性结果中,2种及以上血清型同时阳性为17份,占19.10%(17/89)。结论:我市健康人群普遍存在不同程度和不同血清型的嗜肺军团菌隐性感染,使用中央空调的场所是嗜肺军团菌感染的高危场所,应加强监测。     

大连地区不同人群军团菌感染的比较研究

笔者采用微量凝集试验对３００名健康献血员、１２０名非肺炎免疫功能低下的住院病人及１５８名（７４名双份血清）肺炎病人血清三种（１０型）军团菌抗体进行了检测。结果表明，大连地区存在所测三种（１０型）军团菌感染。三组人群各型之间抗体阳性率及ＧＭＴ均有显著性差异，均以Ｌｐ６最高，Ｌｐ１、Ｌｐ８次之。Ｌｐ１、Ｌｐ２、Ｌｐ６、Ｌｐ８抗体阳性率及ＧＭＴ在三组人群之间有显著性差异，肺炎组最高，非肺炎免疫功能低下组次之。提示大连地区军团菌感染以Ｌｐ６、Ｌｐ１、Ｌｐ８为优势种型，人群中隐性感染、亚临床感染和军团菌肺炎同时存在。     

山西省部分健康人群血清军团菌抗体检查

目的：了解山西地区军团菌感染的菌型分布特点和优势种型，为扩大军团菌监测范围和加强军团菌病防治提供新依据。方法：采用微量凝集试验对336名健康献血员和门诊体检者进行了9种血清型军团菌抗体测定。结果：所测军团菌各型均有阳性出现，呈出现感染多型性特征，Lp1阳率最高（9．68％），非嗜肺军团菌抗体以Lc(7.43%),Lmic(6.79％）和Lmic-T(5.21%)为我省感染流行的的优势种型。结论：山西健康人群普遍存在不同程度和不同种型的军团菌感染，临床诊断时应以超过当地正常滴度上限为标准。     

放射工作人员抗EB病毒抗体水平初探

２７８名放射治疗医技师与放射探放人员ＩｇＡ／ＶＣＡ抗体滴度≥１：１０有７４例（占２６．６％），其几何平均滴度为１：１１．８，显著高于本地区一般人群的相应水平。推测职业性长期小剂量电离辐射可能使潜于人体内的ＥＢ病毒受到激活。     

Legionellosis in meat-packing combines of the Lithuanian SSR

The article presents the results of a study of Legionella pneumophila morbidity in Lithuanian meat-processing factory workers, as well as the specific position of legionellosis in the fever diseases structure among the workers of the industry. The technique showed that Legionella pneumophila 1st serogroup seropositive reaction was traced among the healthy workers in 0.2% (antibody titer 1:64). Rather high percentage (7.1%) of persons with specific antibodies was found among those who had suffered the fever disease 6 month before the examination. Among 191 fever patients examined, in 35 (18.3%) cases antibodies against L. pneumophila were detected in diagnostic titers. In 26 workers legionellosis was diagnosed as a result of serologic testing, and Pontiac fever cases were predominant. 1 case was subsequently followed by pneumonia. A chronic nature of epidemic manifestations of legionellosis was established. The pathogenic antigen was detected in 4 of 32 water samples taken from the factory water pipes.     

Role of environmental surveillance in determining the risk of hospital-acquired legionellosis: a national surveillance study with clinical correlations.

OBJECTIVE: Hospital-acquired Legionella pneumonia has a fatality rate of 28%, and the source is the water distribution system. Two prevention strategies have been advocated. One approach to prevention is clinical surveillance for disease without routine environmental monitoring. Another approach recommends environmental monitoring even in the absence of known cases of Legionella pneumonia. We determined the Legionella colonization status of water systems in hospitals to establish whether the results of environmental surveillance correlated with discovery of disease. None of these hospitals had previously experienced endemic hospital-acquired Legionella pneumonia. DESIGN: Cohort study. SETTING: Twenty US hospitals in 13 states. INTERVENTIONS: Hospitals performed clinical and environmental surveillance for Legionella from 2000 through 2002. All specimens were shipped to the Special Pathogens Laboratory at the Veterans Affairs Pittsburgh Medical Center. RESULTS: Legionella pneumophila and Legionella anisa were isolated from 14 (70%) of 20 hospital water systems. Of 676 environmental samples, 198 (29%) were positive for Legionella species. High-level colonization of the water system (30% or more of the distal outlets were positive for L. pneumophila) was demonstrated for 6 (43%) of the 14 hospitals with positive findings. L. pneumophila serogroup 1 was detected in 5 of these 6 hospitals, whereas 1 hospital was colonized with L. pneumophila serogroup 5. A total of 633 patients were evaluated for Legionella pneumonia from 12 (60%) of the 20 hospitals: 377 by urinary antigen testing and 577 by sputum culture. Hospital-acquired Legionella pneumonia was identified in 4 hospitals, all of which were hospitals with L. pneumophila serogroup 1 found in 30% or more of the distal outlets. No cases of disease due to other serogroups or species (L. anisa) were identified. CONCLUSION: Environmental monitoring followed by clinical surveillance was successful in uncovering previously unrecognized cases of hospital-acquired Legionella pneumonia.     

Prospective 3-year surveillance for nosocomial and environmental Legionella pneumophila: implications for infection control.

OBJECTIVES: To perform a 3-year, prospective surveillance program for legionnaires disease (LD) in a large university hospital in Rome, and to assess the usefulness of the hospital water monitoring program in predicting the risk of nosocomial LD. METHODS: Samples from patients with new cases of nosocomial pneumonia were sent for legionella laboratory investigations. Meanwhile, water samples for bacteriological analysis were collected every 6 months from high- and medium-risk hospital wards (10 in total). Legionella pneumophila isolates collected were serotyped and analyzed by pulsed-field gel electrophoresis. RESULTS: From June 2001 through May 2004, the pneumonia surveillance identified one case of nosocomial LD among 43 cases of nosocomial pneumonia (2.3%). Environmental investigations detected L. pneumophila in 12 (18.7%) of the 64 water samples, of which 50% belonged to serogroup 1. The L. pneumophila count and the percentage of positive locations never exceeded 10(2) colony-forming units/L and 20%, respectively, except when the LD nosocomial case occurred (positive water samples, 40%; L. pneumophila count, <10(2) colony-forming units/L). Genotyping showed 3 prevalent clones of L. pneumophila in the water distribution network, of which one persisted over the 3 years. One clone contained 3 different L. pneumophila serogroups (2, 4, and 6). CONCLUSIONS: The low incidence of nosocomial cases of LD appears to be associated with a low percentage (<20%) of positive water samples per semester and with a low contamination level (<10(2) colony-forming units/L). An infection control system for nosocomial LD should, therefore, be based on both environmental and clinical surveillance, together with the appropriate maintenance of the hospital water distribution system.     

Incidence of Legionella in warm water systems in Saxony-Anhalt

The incidence of Legionella in warm water systems of Sachsen-(Saxony-)Anhalt was investigated. The Legionella were isolated from water samples using plate cultures followed by serotyping methods. In high-risk areas of Legionella infections such as hospitals and homes for the aged, 48% respectively 43% of the samples were positive. Warm water systems of 61% of the hospitals and 43% of homes for aged people were found to be contaminated with Legionella. The number of Legionella were most frequently (50.7%) between 10 and 100 colony-forming units/ml (cfu/ml). High-level Legionella contamination (> 1000 cfu/ml) were detected only in 0.6% of the samples. Legionella pneumophila serogroup 1 (L.p. SG 1) was identified rarely. The reasons for positive Legionella findings are old drinking water heating systems and conduits. To decrease Legionella growth, reconstruction of the old systems according to the recommendations [1, 2] is imperative.     

冬夏季军团菌自然感染状况的研究

本文用定群研究的方法,观察了南京地区自然人群冬夏季LDB₁型抗体的分布动态。结果表明,夏季抗体阳性率13.03%(29/990),比冬季的1.65%(19/1146)高 7.89倍,而GMT夏季(1:5.05)比冬季(1:1.67)高3倍。夏季抗体滴度 ≥ 1:128者4人(0.4%),冬季最高滴度1:32(1人)。男女间抗体阳性率和GMT无明显差异。各年龄组和不同职业人群的抗体水平夏季均高于冬季。各职业人群的抗体阳性率以养路工最高,幼儿园儿童最低。此外,对LDB感染季节性特征的意义。感染情况和可能传播方式等问题进行了讨论。     

Legionella pneumophila serogroup 1 population in Italy by monoclonal subtyping

The Oxford panel of monoclonal antibodies was used to subtype 83 strains of Legionella pneumophila serogroup 1 of human and environmental origin. The International panel was also used to subtype 50 of them. All the 18 patients' isolates were of the Pontiac subgroup, and 40/43 of the environmental strains of the Pontiac subgroup were associated with human infection. The remaining environmental strains were subgroups Olda (15 strains), Camperdown (5 strains), and Bellingham (2 strains). The Philadelphia subgroup was the commonest among the environmental strains tested with the international MABs panel. This study confirms previous findings that L. pneumophila serogroup 1 isolates with the Pontiac (Oxford panel) or MAB-2 (international panel) reacting antigen marker seem to be more virulent than the other subgroups.     

Soil as a source of Legionella pneumophila serogroup 1 (Lp1)

OBJECTIVE: To investigate the potential source of a case of Legionnaires' disease caused by an unusual serotype of Legionella pneumophila serogroup 1 (Lp1) in regional Victoria in May 2001. METHOD: Epidemiological and environmental investigation of the source of infection of a case of Legionnaires' disease in regional Victoria in May 2001. RESULTS: Extensive environmental investigations did not reveal any cooling water tower systems close to the residence or the shopping centre that the case visited prior to illness. The sputum culture and a soil sample from the field at the plant nursery where the case worked prior to illness were both positive for Legionella pneumophilia serogroup 1, MDU pulsovar 97:103. CONCLUSION: Legionella pneumophila has been found in soil and was further found to be associated with a case of Legionella pneumophila. IMPLICATIONS: Public health authorities should consider exposures to soil and potting mixes when investigating cases of Legionella pneumophila where the case has no apparent association with cooling towers. Safe gardening practices should be promoted among the community.     

Predicted coverage by 4CMenB vaccine against invasive meningococcal disease cases in the Netherlands

Neisseria meningitidis serogroup B is a major cause of invasive meningococcal disease in Europe. In the absence of a conjugate serogroup B vaccine, a subcapsular 4CMenB vaccine was developed. Data on 4CMenB vaccine efficacy is still limited. Recently, genomic MATS (Meningococcal Antigen Typing System) was developed as a tool to predict strain coverage, using vaccine antigens sequence data. We characterized all invasive meningococcal isolates received by the Netherlands Reference Laboratory for Bacterial Meningitis (NRLBM) in two epidemiological years 2017–2019 using whole-genome sequencing and determined serogroup, clonal complex (cc) and estimated 4CMenB vaccine coverage by gMATS. Of 396 cases of invasive meningococcal disease, corresponding to an incidence of 1.22 cases/10⁵ inhabitants, 180 (45%) were serogroup W, 155 (39%) serogroup B, 46 (12%) serogroup Y, 10 (3%) serogroup C, 2 non-groupable (0.5%) and 3 (0.7%) unknown. The incidence was the highest among 0–4 years olds (4 cases/10⁵ inhabitants), and 57/72 (79%) of these cases were serogroup B. Serogroup W predominated among persons 45 years of age or older with 110/187 (59%) cases. Serogroup B isolates comprised 11 different clonal complexes, with 103/122 (84%) isolates belonging to 4 clonal complexes: cc32, cc41/44, cc269 and cc213. In contrast, serogroup W isolates were genetically similar with 95% belonging to cc11. Of 122 serogroup B isolates, 89 (73%; 95% CI: 64–80%) were estimated to be covered by 4CMenB and the degree of coverage varied largely by clonal complex and age. Among the 0–4 year olds, 25 of 43 (58%; 95% CI: 43–72%) MenB isolates were estimated to be covered. Since the coverage of the 4CMenB vaccine is dependent on circulating clonal complexes, our findings emphasize the need for surveillance of circulating meningococcal strains. In addition, estimation of age specific coverage is relevant to determine the right target age group for vaccination.     

Nosocomial legionella pneumonia: demonstration of potable water as the source of infection

From January 1983 until December 1985, 35 cases of sporadic nosocomial legionella pneumonia, all caused by Legionella pneumophila, were diagnosed in a university hospital. L. pneumophila serogroup (SG) 1 was cultured from 12 of the 35 cases and compared to corresponding L. pneumophila SG 1 isolates from water outlets in the patients' immediate environment by subtyping with monoclonal antibodies. The corresponding environmental isolates were identical to 9 out of 12 (75%) of those from the cases. However, even in the remaining three cases identical subtypes were found distributed throughout the hospital water supply. From the hospital water supply four different subtypes of L. pneumophila SG 1 were isolated, three of which were implicated in legionella pneumonia. Of 453 water samples taken during the study 298 (65.8%) were positive for legionellae. Species of Legionella other than L. pneumophila have not been isolated. This may explain the exclusiveness of L. pneumophila as the legionella pneumonia-causing agent. Our results suggest that the water supply system was the source of infection.     

Different growth rates in amoeba of genotypically related environmental and clinical Legionella pneumophila strains isolated from a thermal spa

Two cases of legionellosis occurring 3 years apart were acquired in the same French thermal spa and were apparently due to the same strain of Legionella pneumophila serogroup 1, as shown by genomic macrorestriction analysis. Minor differences between the two isolates were found by random amplification PCR profiling which showed an additional band with one of the isolates. Analysis of 107 L. pneumophila strains isolated from the spa waters by genome macrorestriction failed to identify the infective strain, but a closely related L. pneumophila serogroup 3 strain differing from the clinical isolates by only one band was found. To determine if the clinical L. pneumophila serogroup 1 isolates was better adapted for intracellular multiplication than related serogroup 3 environmental isolates, the growth kinetics of six isolates were determined in co-culture with Acanthamoeba lenticulata. One clinical isolate failed to grow within amoeba, while the other clinical isolate yielded the highest increase in bacterial cell count per amoeba (1,200%) and the environmental isolates gave intermediate values. Genetic analysis of L. pneumophila isolates by DNA macrorestriction does not therefore appear to reflect their growth kinetics within amoeba, and is not sufficiently discriminatory to identify potentially virulent strains.