Evaluation of the efficacy of ultraviolet irradiation for disinfection of hospital water contaminated by Legionella

We evaluated the efficacy of the ultraviolet irradiation on hospital water colonized by Legionella pneumophila serogroup 3, by inserting a lamp system on a hot water pipe supplying a small area. Cultures were performed for four months from 5 L samples of water, collected before and after the ultraviolet treatment at the lamp unit and from two distal points. Irradiation was effective immediately after disinfection (<10 cfu/L), even when the incoming water was highly contaminated. One distal point showed little or no contamination (<10–20 cfu/L), while the other showed little to moderate contamination (<10³ cfu/L). We conclude that ultraviolet irradiation is useful to protect the water system in small area; however, because of the lack of residual activity, it should be combined with other methods of disinfection. Maintenance of the water system is also necessary in order to reduce biofilm formation and Legionella recolonization.     

Legionella species and serogroups in Malaysian water cooling towers: identification by latex agglutination and PCR-DNA sequencing of isolates

In this study, we investigated the distribution of Legionella species in water cooling towers located in different parts of Malaysia to obtain information that may inform public health policies for the prevention of legionellosis. A total of 20 water samples were collected from 11 cooling towers located in three different states in east, west and south Malaysia. The samples were concentrated by filtration and treated with an acid buffer before plating on to BCYE agar. Legionella viable counts in these samples ranged from 100 to 2,000 CFU ml^-1; 28 isolates from the 24 samples were examined by latex agglutination as well as 16S rRNA and rpoB PCR-DNA sequencing. These isolates were identified as Legionella pneumophila serogroup 1 (35.7%), L. pneumophila serogroup 2–14 (39%), L. pneumophila non-groupable (10.7%), L. busanensis, L. gormanii, L. anisa and L. gresilensis. L. pneumophila was clearly the predominant species at all sampling sites. Repeat sampling from the same cooling tower and testing different colonies from the same water sample showed concurrent colonization by different serogroups and different species of Legionella in some of the cooling towers.     

Isolation of Legionella species/serogroups from water cooling systems compared with potable water systems in Spanish healthcare facilities

Surveillance of Legionella spp. in hospital water systems was performed in forty-four inpatient healthcare facilities in Spain during 2005-2006. A total of 2,341 samples were collected: 470 from cooling systems (cooling towers) and 1,871 from potable water systems. The latter included 211 from cold-water tanks and 260 from hot-water tanks, totalling 471 from central water reservoirs 136 from showers, 1,172 from unfiltered taps and 92 from filtered taps, totalling 1,400 from peripheral points. Temperature, chlorine levels and the presence of Legionella spp. were determined. In all, 373 (15.9%) samples yielded Legionella spp. Significantly higher isolation rates were obtained from cooling towers (23.8%) versus cold- and hot-water tanks (approximately 4.7%), due to the significantly higher number of samples positive for serogroup 1 (19.4 vs 0.9-3.5%). In potable water systems, no differences were found between central water tanks and showers, but significant differences in isolation rates between central water tanks and unfiltered taps were observed (4.7 vs 19.6%) due to differences in non-serogroup 1 L. pneumophila. Filters significantly decreased isolation rates of these serotypes (11 vs 0%). Some seasonal differences were noted, with higher isolation rates in summer for legionella serogroup 1 in cooling systems and for L. pneumophila serogroups 2-14 in potable water systems. In regression models, higher temperatures were associated with colonisation in cooling systems, while lower chlorine levels were associated with colonisation in potable water systems.     

Outbreak of Legionnaires' disease in West Fife: review of environmental guidelines needed

OBJECTIVES: The objectives of this study were to investigate the source of and outbreak of Legionnaires' disease in West Fife in 2004; to control the spread of legionella from this source; and to make recommendations for future practice based on the findings from the investigation. STUDY DESIGN: Outbreak investigation. METHODS: A multi-agency team investigated links between the cases of legionellosis using detailed interviews, movement mapping, a timeline and extensive environmental sampling. RESULTS: The investigation found evidence that individuals affected by legionella during this outbreak had been in, or near (within 800 m), sullage tanks in Rosyth Dockyard within a period of 4 months. CONCLUSIONS: In the absence of laboratory isolation of Legionella spp. from the human cases, it was impossible to state definitely that a previously unrecognized source of environmental legionella aerosolization was responsible for the outbreak. However, strong epidemiological and environmental evidence would support this hypothesis.     

Plasmid profiles of Legionella spp. isolates,Italy

Plasmid analysis and restriction-endonuclease digestion were used to study 54 clinical and environmental Legionella strains. Plasmids with approximate molecular masses of 40, 50, 70, and 90 megadaltons (Mdal) have been isolated from L. pneumophila serogroup 1 strains. One L. jordanis strain contained two plasmids of 25 and 70 Mdal. Restriction analysis of clinical and related hospital-environmental isolates resulted in identical patterns. Geographic diversity is shown for strains of different origin.     

上海市部分地区中央空调冷却塔水军团菌生态学研究

目的：探索中央空调冷却塔水军团菌生态学特征,为制定军团菌的预防控制措施提供依据。方法：采用分离培养的方法,对上海市部分地区中央空调冷却塔水中和冷却塔壁生物膜内的军团菌特征进行实验研究。结果：中央空调冷却塔水军团菌的消长与气温关系明显,尤其在夏秋季节,军团菌含量较高;在气温较低的冬春季节,水中军团菌不能检出,但中央空调冷却塔壁生物膜上仍能检出军团菌。结论：中央空调冷却塔水中军团菌消长具有季节性,生物膜为军团菌躲避不利环境提供庇护场所。     

细辛脑注射液治疗儿童呼吸系统疾病的有效性及安全性的系统评价

目的系统评价细辛脑注射液治疗儿童呼吸系统疾病的有效性和安全性。 方法计算机检索MEDLINE数据库、Cochrane图书馆临床对照试验库(CENTRAL)、维普数据库(VIP)、中国期刊全文数据库(CNKI)、中国生物医学文献数据库(CBM)及万方数据库等中、英文数据库,检索年限为各数据库自建库至2014年6月,同时结合手工检索,获得关于细辛脑注射液治疗儿童呼吸系统疾病的随机对照试验(RCT)研究文献。由2位经该项目培训合格的研究者,对纳入文献进行资料提取、质量评价及交叉核对。采用RevMan 5.2软件,对细辛脑注射液治疗儿童呼吸系统疾病的有效性和安全性进行meta分析。 结果经检索,共计14篇关于细辛脑注射液治疗儿童呼吸系统疾病的有效性和安全性的RCT研究文献纳入本研究,纳入患儿共计1 839例。纳入文献中4篇为中等质量研究文献,10篇为低质量研究文献。本研究meta分析结果显示：①细辛脑注射液能有效治疗儿童毛细支气管炎、肺炎、支气管炎和喘息性疾病。②在治疗儿童毛细支气管炎方面,细辛脑注射液的总有效率优于氨茶碱(RR＝1.25,95%CI：1.13～1.38,P<0.000 1)或鱼腥草(RR＝1.32,95%CI：1.12～1.56,P＝0.001 0),但尚不能认为其优于抗病毒药物利巴韦林(RR＝1.25,95%CI：0.86～1.83,P＝0.250 0)。③在治疗儿童肺炎方面,细辛脑注射液的总有效率优于利巴韦林(RR＝1.14,95%CI：1.04～1.25,P＝0.005)或抗菌药物(RR＝1.19,95%CI：1.04～1.40,P＝0.040)。④在治疗儿童支气管炎方面,细辛脑注射液的总有效率优于氨茶碱(RR＝1.17,95%CI：1.04～1.32,P＝0.01),尚不能认为其优于氨溴索(RR＝1.09,95%CI：0.99～1.19,P＝0.07)或对症治疗(RR＝1.19,95%CI：0.94～1.51,P＝0.15)。⑤在治疗毛细支气管炎、哮喘并肺部感染等儿童喘息性疾病方面,细辛脑注射液的总有效率高于炎琥宁,且差异有统计学意义(97.6% vs 90.3%,χ²＝11.12,P<0.01)。⑥在安全性方面,细辛脑注射液的变态反应和胃肠道不良反应发生率与对照组比较,差异无统计学意义(P>0.05);导致的患儿烦躁、哭闹发生率较对照组低,且差异有统计学意义(RR＝0.24,95%CI：0.09～0.67,P＝0.007)。 结论细辛脑注射液可有效治疗儿童呼吸系统疾病,但因纳入研究的方法学质量不高,可能存在选择偏倚、实施偏倚及测量偏倚,因此该药的确切疗效及安全性尚有待更多高质量、大样本及较长随访时间的随机双盲对照试验予以证实。     

Plasmid profiles of legionella pneumophila strains isolated in Spain

An assay for plasmid DNA content was carried out in 100 strains of Legionella pneumophila of distinct serogroups and isolated from various sources (clinical, environment). The strains were isolated from different geographic regions in our country. The presence of plasmids was proved in one of the 11 clinical isolates and in 68 of the 89 isolated of environmental origin studied. In the strains belonging to serogroup 1 and isolated in our region (Cantabria), three plasmid profiles were observed, whereas in strains of the same serogroup from other geographic regions, two profiles were shown which exhibited differences compared to the former ones. Analysis by means of restriction endonucleases suggested that plasmids of similar size in serogroup 1 strains of different source, were related. The results obtained do not appear to reveal any correlation between plasmid profile and source of isolation or serogroup.Corresponding author.     

Plan for the control of Legionella infections in long-term care facilities: role of environmental monitoring

In accordance with the international and national guidelines, the Emilia-Romagna Region (Italy) has established regional guidelines for the surveillance and prevention of legionellosis based on the concept of risk assessment, with particular attention to environmental monitoring. The aim of this study was to verify how environmental surveillance in the context of risk assessment plans could help to guide decisions about preventive strategies against Legionella infections in Long Term Care Facilities (LTCF). In six LTCFs in the city of Bologna (Emilia-Romagna Region) a self-control plan was implemented that included the environmental monitoring of Legionella spp. and the surveillance of hospital-acquired Legionnaires' Disease. At baseline, four hot water systems were colonized by Legionella pneumophila (3 LCTFs) and Legionella londiniensis (1 LCTF). In each establishment specific control measures were adopted based on the characteristics of the system, the virulence of the strain and the level of the contamination. The monitoring, carried out for around two years, was also extended to the ways in which the system and the distal water distribution points were used and maintained with respect to the good practices in operation and management. The adopted actions (shock and/or continuous disinfection treatments) and the implementation of the good practice measures reduced the contamination to acceptable and stable levels. No cases of hospital-acquired legionellosis occurred during the period of study. The environmental surveillance was successful in evaluating the risk and identifying the most suitable preventive strategies.     

1,5-Diaryl-2-ethyl pyrrole derivatives as antimycobacterial agents: Design, synthesis, and microbiological evaluation

During the search of novel antitubercular drugs related to BM 212, new diarylpyrroles were designed and synthesized on the basis of a structure–activity relationship analysis of many pyrroles previously described by us. Among them, 1-(4-fluorophenyl)-2-ethyl-3-(thiomorpholin-4-yl)methyl-5-(4-methylphenyl)-1H-pyrrole (2b) proved to be particularly active, with a minimum inhibitory concentration (MIC, expressed as μg/mL) and a protection index (PI) better than or comparable to those of reference compounds. Also the remaining compounds were very active, although their MIC and PI were in general lower than those of their parent 2-methyl analogues.     

Pseudomonas spp. complications in patients with HIV disease: An eight-year clinical and microbiological survey

Two hundred and twenty-four episodes of Pseudomonas spp. complications that occurred in 179 consecutive patients with HIV infection were retrospectively reviewed. Pseudomonas spp. organisms were responsible for 11.6% of 1933 episodes of non-mycobacterial bacterial diseases (5.4% of 1072 episodes of sepsis), observed over an 8-year period; 20.7% of patients experienced disease relapses (45 episodes). These complications mostly involved lower airways (66 cases), urinary tract (53 episodes), and blood (34 cases), with Pseudomonas aeruginosa isolated in 161 episodes, and other Pseudomonas spp. in the remaining 63 cases. An advanced HIV disease was frequently present (as expressed by a prior diagnosis of AIDS, a low CD4+ lymphocyte count, and leukopenia–neutropenia). Indwelling intravascular and urinary catheters were often associated with bacteremia and urinary tract involvement, respectively. More than 60% of patients were given antibiotics and/or cotrimoxazole in the month preceding the onset of Pseudomonas spp. disease. Bacterial strains isolated from our HIV-infected patients showed a favorable sensitivity to piperacillin, ceftazidime, imipenem, amikacin, tobramycin, and ciprofloxacin. An adequate antimicrobial treatment led to clinical and microbiological cure in 73.2% of patients at the first episode, and in 22.3% more subjects after one or more relapses. A lethal outcome occurred in only eight patients of 179 (4.5%), suffering from a far advanced HIV disease; P. aeruginosa infection directly contributed to death in four cases (sepsis, and/or pneumonia). Nosocomial disease occurred in 46.4% of the 224 episodes, and was significantly related to a previous diagnosis of AIDS, concurrent neutropenia, the occurrence of sepsis or urinary tract infection, disease relapses, the involvement of non-aeruginosa Pseudomonas spp., and a lethal outcome, compared with community-acquired infection. Our experience (the largest reported to date) confirms that Pseudomonas spp. (including non-aeruginosa Pseudomonas spp. organisms) is responsible for remarkable morbidity and mortality among patients with HIV infection, and may pose relevant problems to clinicians and microbiologists involved in the care of HIV-infected patients.     

Ecotoxicological evaluation of cork-boiling wastewaters

Toxicity tests with Vibrio fischeri, Daphnia magna, and Lemna minor were used to evaluate acute and chronic toxicity of cork-boiling wastewaters and correlation analysis was performed with physicochemical parameters. Acute toxicity values (EC₅₀) ranged from 2.3% to 24.2% in the Microtox test and from 4.4% to 29.5% in the Daphnia test. According to these values, 78% of the samples were classified as acutely toxic to the most sensitive species (V. fischeri). Significant correlation was obtained between EC₅₀ and chemical oxygen demand, biochemical oxygen demand after 5 days, total organic carbon, tannin and lignin and total solids. No significant correlation was found between the two acute tests. The D. magna chronic test showed significant differences between all tested concentrations and the control, with an EC₅₀ of 0.32%. An EC₅₀ value of 26.0% was calculated for L. minor. For the analysis of cork-boiling wastewater toxicity and routine biomonitoring, the use of the Microtox test is suggested, to afford greater environmental protection.     

鼠疫耶尔森菌和假结核耶尔森菌基因鉴别方法的建立及评价

目的 建立鼠疫耶尔森菌和假结核耶尔森菌基因鉴别方法。方法 依据鼠疫菌、假结核菌特有的基因组序列["疫岛(PeI)"和"假岛(PsI)"], 与已公布的12株鼠疫菌和4株假结核菌全基因序列进行比对, 设计特异性的引物, 对鼠疫菌、假结核菌和其他肠道细菌进行鉴定。结果 用52株鼠疫菌、57株假结核菌和其他肠道菌株进行验证, 结果显示, 5对鼠疫菌的鉴定引物中, 2对(PeI2和PeI11)仅在52株鼠疫菌中扩出目的条带, 另3对引物(PeI1、PeI3和PeI12)除鼠疫菌外在部分假结核菌株中也扩出目的条带;5对假结核菌鉴定引物中, 1对引物(PsI1)在52株鼠疫菌和57株假结核菌株中扩出目的条带, 4对引物(PsI7、PsI16、PsI18和 PsI19)仅在57株假结核菌株中均扩出目的条带, 在鼠疫菌中未扩出目的条带。结论 用鼠疫菌和假结核菌共有的PsI1序列、鼠疫菌特有的PeI2和PeI11序列及假结核菌特有的PsI7、PsI16、PsI18和 PsI19序列组成的基因鉴别方法, 可以用于鼠疫菌和假结核菌的基因快速鉴别。     

Micronucleus test in freshwater fish species: an evaluation of its sensitivity for application in field surveys

Brown trout, Salmo trutta, European eel, Anguilla anguilla, and European minnow, Phoxinus phoxinus, three fish species inhabiting European freshwater ecosystems, were evaluated for their use as in situ pollution biomarkers using the micronucleus test in renal erythrocytes. Experimental exposure (by immersion) to different concentrations of cyclophosphamide, colchicine, and cadmium showed that brown trout are more sensitive to the three compounds than minnows and eels. In situ surveys of wild freshwater ecosystems with different levels of pollution showed that minnows and eels living in polluted sites do not present higher micronuclei averages than those caught in clean rivers systems, whereas micronuclei are induced in brown trout inhabiting polluted sites. Our results demonstrated the suitability of brown trout for in situ biomonitoring of freshwater ecosystems as well as for laboratory tests using the micronucleus test.     

An evaluation of the impact of a national health demonstration project on testing and management for Chlamydia trachomatis infections in two regions of Scotland

OBJECTIVES: To compare clinical practice relating to testing for, and management of, genital Chlamydia trachomatis infection in the Lothian and Grampian regions of Scotland as part of an evaluation of a Government-funded health demonstration project in Lothian, Healthy Respect. STUDY DESIGN: Clinical audit against standards developed from a national clinical guideline. METHODS: Clinical practice relating to testing for, and management of, genital C. trachomatis infection was assessed against standards for good quality care developed from a national clinical guideline (Scottish Intercollegiate Guidelines Network Guideline 42). Audit methods comprised: postal survey of primary care clinicians; review of referral letters from primary to secondary care; and review of primary and secondary care patient case records. Findings from Lothian and Grampian were compared. RESULTS: Questionnaires were returned by 167 primary care clinicians in Lothian and 96 in Grampian. Clinicians in Lothian and Grampian gave similar responses relating to: testing of symptomatic patients (87 vs 88%); offer of testing for asymptomatic young patients (55 vs 55%); choice of antichlamydial agent (47 vs 42% azithromycin as first line); and follow-up strategies (50 vs 51% offer follow-up in primary care). Clinicians in Lothian were significantly more likely to participate in partner notification work (57 vs 44%; P=0.04) and to agree with statements reflecting 'perceived self-efficacy' in chlamydia-related care (57 vs 48%; P=0.006). Referral letters from primary to secondary care were reviewed for 31 women with genital symptoms in Lothian and 28 in Grampian. More women in Lothian were tested for chlamydia prior to referral (65 vs 39%; difference not significant). Review of primary care records for consultations in young people (145 in Lothian; 203 in Grampian) showed a higher level of chlamydia testing in Grampian (Lothian, 14%; Grampian, 34%; P<0.0001). However, review of secondary care records (n=39) showed a much higher level of testing in Lothian (Lothian, 75%; Grampian, 9%; P<0.0001). Review of secondary care records relating to proven chlamydia-positive women (n=159) suggested better care in Lothian in relation to ensuring antibiotic treatment (Lothian, 91%; Grampian, 74%; P=0.004), and use of the preferred antibiotic, azithromycin (Lothian, 78%; Grampian, 37%; P<0.0001). However, documented referral to a health adviser appeared to be better in Grampian (Lothian, 32%; Grampian, 48%; P=0.048). CONCLUSIONS: During the period of activity of the Healthy Respect demonstration project, few differences were detected between clinicians in Lothian and Grampian with regard to chlamydia-related practice. In both regions, clinicians appeared to be very aware of the need to test for chlamydia in patients with relevant symptoms, but were less likely to offer opportunistic testing to young patients without specific symptoms. These findings suggest that Healthy Respect in Lothian has had little impact on clinicians. However, these findings must be considered within the context of a broader evaluation, and it is noteworthy that the few significant differences that were detected tended to suggest better practice in Lothian.     

Epidemiological,clinical and microbiological features of Yersinia enterocolitica infections in a community during a four-year period

Epidemiological and clinical features of 17 cases (13 children) of yersiniosis treated in a hospital over a four-year period, as well as factors associated with virulence, antibiotic resistance and plasmids in Yersinia enterocolitica strains from these patients were studied. The proportion of Y. enterocolitica was 3.57% of all fecal cultures positive for enteric pathogens, with 13 sporadic episodes and one outbreak. In 11 cases the infection was unimicrobial. The clinical presentation was: gastroenteritis (14 cases), pseudoappendicitis (1 case) and asymptomatic (2 cases). Eight cases needed hospital care, and 8 required antimicrobial treatment. None of the isolated bacterial strains produced pyrazinamidase, hemolysins, elastase, fibrinolysine, colicines or aerobactin. Eight strains showed calcium dependence, 7 of them exhibited autoagglutination, serum resistance, crystal violet binding and carried a 42 MDa plasmid related with virulence. Two strains carried a 3.3 MDa R-plasmid that encoded streptomycin-sulfadiazine resistance. The restriction analysis showed that the virulence plasmids constitute one variety and R-plasmids another.     

The role of the World Health Organization in the control of rickettsial diseases

The World Health Organization (WHO) pays great attention to the problem of rickettsial diseases. A network exists of Collaborating Centres for Rickettsial Reference and Research, which are designated by WHO.A WHO Consultation on the Laboratory Diagnosis of Rickettsial Diseases was held in 1987. In accordance with the recommendations of this consultative group, WHO first established The Project on Global Surveillance System for Rickettsial Diseases, with the immediate objective of obtaining reliable data on the global prevalence and distribution of rickettsial diseases. This information should contribute directly to the principal objective of reducing morbidity and mortality due to rickettsial diseases. An additional objective is to identify and characterize strains of pathogenic rickettsiae from various localities throughout the world. The final objective of the above study is to transfer the existing diagnostic technology to laboratories in developing countries. Under the auspices of this Project a diagnostic kit was developed for identification of antibodies with antigens of R. prowazekii and R. conorii in the indirect immunofluorescence test. About 20 laboratories in various countries are participating in this Project. Training courses have been organized for participants from countries in Africa and South-East Asia. The first stage of the Project will be evaluated in 1991 and, depending on the outcome of the first stage, a larger programme would be considered for subsequent years.Presented at the 4th International Symposium on Riskettsiae and Rickettsial Diseases, Pietany, C.S.F.R., 1–6 October, 1990.     

Intrinsically vancomycin-resistant Gram-positive organisms: clinical relevance and implications for infection control

Intrinsic resistance to vancomycin in gram-positive bacteria presumably predates acquired vancomycin resistance in enterococci but it has only recently generated interest. Intrinsically resistant enterococci possessing the vanC gene and the non-enterococcal genera Leuconostoc, Lactobacillus, Pediococcus and Erysipelothrix are known to cause human infection. This review examines the available data on their identification, resistance mechanisms, epidemiology, clinical infections and antimicrobial susceptibility. Intrinsically vancomycin-resistant gram-positives are usually opportunistic pathogens. Although serious infections may occur, treatment options remain available. No additional infection control measures for the intrinsically resistant genera appear justified with currently available evidence, although vigilance should be maintained to detect future changes in susceptibility patterns.     

An overview of research on ehrlichiosis

Ehrlichiosis is a disease caused by a group of rickettsiae, known as ehrlichiae, which parasitize circulating leukocytes of man and a variety of domestic and wild animals. A characteristic morphologic feature of ehrlichiae is their occurrence in membrane-bound vacuoles in the cytoplasm of leukocytes, forming inclusions that contain variable numbers of organisms. The tick is the apparent vector of ehrlichiae, but such evidence is not available for all species.Presented at the 4th International Symposium on Rickettsiae and Rickettsial Diseases, Piestany, C.S.F.R., 1–6 October, 1990.