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G Wewalka

Publications and source records attributed to G Wewalka.

At least 19 recordsLinked to original sources
PubMed2005

Surveillance of Legionnaires' disease in Austria.

Seven foreign cases of travel-associated Legionnaires' disease were associated with two neighbouring tourist villages in Austria between 1992 and 2004. The seven foreigners stayed in four hotels located in a geographical diameter of less than 10 km. Two cases were diagnosed in The Netherlands and five in the UK. The first case occurred in 1992, while the remaining cases clustered between August 2000 and April 2004. None of these cases was reported officially as part of a hotel-associated cluster, thereby highlighting several weaknesses of the infectious disease control systems involved.

Adult↗
PubMed2002

Pan-European study on culture-proven Legionnaires' disease: distribution of Legionella pneumophila serogroups and monoclonal subgroups.

This pan-European study included unrelated strains of Legionella pneumophila obtained from 1335 cases of Legionnaires' disease. The isolates were serotyped into the serogroups 1 to 15 by monoclonal antibodies (MAb) and/or rabbit antisera. Additionally, MAb subgrouping was undertaken for isolates belonging to serogroups 1, 4, and 5. Monoclonal types of serogroup 1 were subdivided as having, or not having, the virulence-associated epitope recognized by the MAb 3/1 (Dresden Panel). This epitope is not present on strains belonging to any other serogroups. Taking all Legionella incidents together, MAb 3/1-positive cases were most frequent (66.8%); 11.7% of the isolates belonged to MAb 3/1-negative serogroup 1 subgroups and 21.5% to other serogroups, with serogroups 3 and 6 predominating. Among all serotypes discriminated in this study, monoclonal subtype Philadelphia was the most frequent. If categories of infection were considered, the proportion of MAb 3/1-negative strains differed significantly ( P<0.0005) between community-acquired cases (139/510; 27.3%) and travel-associated (42/295; 14.2%) or hospital-acquired infections (176/329; 53.5%). Moreover, taking distribution in different European areas into account, the proportion of MAb 3/1-negative strains was significantly higher in the Scandinavian region than in the Mediterranean countries or the UK for both community-acquired (48.7% vs. 18.6% or 12.0%; P<0.0005) and nosocomial cases (87.7% vs. 32.6% or 52.6%; P</=0.0007).

Animals↗
PubMed2001

The influence of hand hygiene prior to insertion of peripheral venous catheters on the frequency of complications.

In a prospective multi-centre study involving 1132 peripheral venous catheters in three hospitals, the relationship between various measures of hand hygiene before insertion of peripheral venous catheters and the frequency of infectious complications', such as local reddening, swelling, pain, purulence and fever of unknown origin, were analysed. For documentation of the relevant data, special protocol forms, one for each catheter, were filled in at the time of insertion and removal of catheters. In comparison with simple hand washing, disinfection of hands before the insertion or wearing of gloves resulted in significantly fewer complications (relative risk 0.59 and 0.66, respectively). Normal hand washing was no better than no hand hygiene (relative risk 1.13), with regard to reduction of complications. This underlines the necessity of employing more effective measures of hand hygiene. The frequency of complications was dependent on the duration of peripheral venous catheterization. Catheters inserted in the operating room had a significantly lower risk of complications than catheters inserted on the ward or in the outpatient unit.

Aged↗
PubMed2000

Implementation of a molecular typing system to support epidemiological investigations in the tuberculosis health care system in Vienna.

Tuberculosis continues to be one of the predominant infectious diseases. Effective control of its spread requires that sources of infection and routes of transmission be disclosed as quickly as possible. At present such investigations are still performed by conventional epidemiological methods. In the recent past, however, molecular typing systems were added to the spectrum of epidemiological tools. Unfortunately, they were applied to retrospective investigations rather than used as an aid in the health care system. In this study, 515 Mycobacterium tuberculosis strains isolated during 1997 and 1998 in Vienna were analysed by spoligotyping, a molecular technique requiring no further cultivation of mycobacteria. The study was aimed to assess the suitability of the method as a quick means of disclosing new cases. Thus, clusters obtained by spoligotyping were analysed along with demographic and epidemiological data and compared with clusters obtained by conventional epidemiological techniques alone. In addition, spoligotype-forming clusters were matched with an international database containing spoligotypes from four different studies. Of 515 isolates, 107 showed an unique pattern. The remaining 408 isolates were distributed into two large clusters of 82 and 73 isolates and into 49 smaller ones consisting of 2 to 33 isolates each. The two spoligotypes forming the large clusters were identical with the most prevalent spoligotypes in the world. Therefore, for the tuberculosis authorities, information was only gained by excluding rather than tracing possible ways of transmission. Twenty-two of the 49 spoligotypes forming smaller clusters were identical with strains found in other parts of the world. Seventeen of 22 infection chains assumed by conventional investigations were confirmed by spoligotyping. In small clusters, an additional 24 infections were assumed due to similarities such as living conditions or socioeconomic status. In 27 clusters, all patients sharing the same strain belong to the same country or geographical area. In conclusion, spoligotyping proved suitable as an early guide in conventional investigations to trace routes of M. tuberculosis transmission in a community. However, when a strain isolated from a patient belongs to a spoligotype shared by many isolates, a second molecular typing method is required.

Austria↗
PubMed1995

[Efficacy of various methods for preoperative vaginal antisepsis].

In a prospective clinical study we investigated 115 patients prior to vaginal surgical interventions to determine the antimicrobial efficacy of six different procedures for vaginal antisepsis. To sample the microorganisms we used a cotton swab moistened with a neutralising fluid. Immediately after the time of action of the antiseptic procedures (3 minutes), providone-iodine solution, applied undiluted or diluted 1:10, yielded the strongest median reduction of the vaginal flora (log RF 3.60 and 2.68, respectively). Of three detergents with antiseptic efficacy, octenidine 0.1% was the most efficient formula (log RF 2.32). After 30 minutes the log reduction factors (log RF) of almost all procedures (log RF 2.79-3.25) were in a fairly close range, excepting chlorohexidine 0.05% (log RF 2.07). Overall, the antiseptic detergents showed a marked residual effect, which was less pronounced, if at all, with providone-iodine solutions. A germ-reducing effect of povidone-iodine vaginal suppositories, applied 2 to 3 hrs prior to surgery, was not confirmed, while additional findings indicated that providone-iodine solution applied with the help of a vaginal douche yields a similarly strong germ reduction as the application by means of a ball swabs.

Adult↗
PubMed1995

[Genomic DNA fingerprints of Legionella pneumophila serogroup 2 strains as an epidemiologic marker].

Using pulsed-field gel electrophoresis, DNA fingerprints of eleven Legionella pneumophila isolates of serogroup 2 were generated. It was shown that two strains from a patient suffering from pneumonia as well as three environmental strains isolated from the shower in the hotel where the patient stayed 5 days before his illness were identical. Six strains of the same serogroup isolated from other sources were clearly separated. Thus, DNA fingerprints by pulsed-field gel electrophoresis are excellent epidemiological markers for the rarely occurring serogroup 2 of Legionella pneumophila.

Antibodies, Monoclonal↗
PubMed1994

Legionella pneumonia in transplant recipients: a cluster of cases of eight years' duration.

Infection with Legionella is often encountered in immunosuppressed patients, especially in recipients of renal allografts. From January 1985 until April 1993 14 cases of nosocomial legionella pneumonia were diagnosed (four by culture, 10 by serological methods) on the surgical transplantation unit of Innsbruck University Hospital. All isolates from patients and from the building's hot water were found to be Legionella pneumophila serogroup 1. They were indistinguishable from each other by monoclonal antibody subtyping and restriction fragment length polymorphism pattern and thus indicated a series of infections originating from the same source during a period of more than 8 years. Repeated efforts to control Legionella by raising the temperature in the hot water lines failed to bring permanent success. Replacing the central hot water supply with small electric water heaters installed in the patient rooms on the transplant ward now seems to have reduced the incidence of legionellosis on this unit. However, further infections occurring in transplant patients in other surgical departments in the same building indicate that a major renovation of the whole surgical building's hot water system is necessary.

Adult↗
PubMed1993

Genital antisepsis--test methodology and efficacy of povidone-iodine.

Indications for antiseptic prophylaxis include use prior to urinary catheterization and other transurethral instrumentations, diagnostic or therapeutic instrumentation of the cavum uteri, and operations on the external genitalia and the vagina. Indications for antiseptic therapy include treatment of wounds and of infections of the genital tract and also include treatment of the vaginas of pregnant women to prevent infection in the newborn. For prophylactic antisepsis the aim is the optimal reduction of potentially pathogenic microorganisms. In some fields of application, e.g. before urinary catheterization, an immediate effect on the mucous membrane is required, but on other occasions, such as transvaginal operations, an additional sustained effect is desired. Testing the efficacy of mucous membrane antiseptics, especially for the genital tract, necessitates the establishment of standardized test methods. The variability in vaginal flora at various ages makes it reasonable to study women aged 20-50 years. Studies presented in this paper indicate that microorganism sampling using a cotton swab moistened with neutralizing fluid can be favoured compared to using a rinsing technique and that anaerobic culture techniques enable the measurement of the high reduction factors achieved by very efficient antiseptic procedures. Test methods validated for hand disinfectants are used for calculations and statistical evaluation. The antimicrobial efficacy of six vaginal antiseptic procedures were compared in patients prior to vaginal surgery. Three minutes after treatment, the highest mean reduction (log RF) of the normal vaginal flora as well as of potentially pathogenic microorganisms was obtained by povidone-iodine solution undiluted and povidone-iodine solution 1:10 (log RF 3.60 and 2.68, respectively). Out of three detergents with antimicrobial efficacy, octenidine 0.1% was the most effective preparation (log RF 2.32). Chlorhexidine 0.1%, hexetidine 0.1% and chlorhexidine 0.05% led to lower reduction factors (log RF 1.80, 1.62 and 1.02, respectively). After 30 minutes the log reduction factors were approximating each other in nearly all procedures (log RF 2.79-3.25) except the log RF derived from the procedure performed using chlorhexidine 0.05% (log RF 2.07). Povidone-iodine solutions seem to be the method of choice for mucous membrane antisepsis where an immediate effect is required. If a long period of action is needed all procedures examined, except chlorhexidine 0.05%, are acceptable.

Adult↗
PubMed1991

Educational programmes for infection control in Austria.

Educational aims and strategies (simply arousing awareness, sensitivity and understanding; and/or training in practical skills and knowledge; or the ability to teach infection control, and to convince those taught) depend on the target group. Infection control is part of the curriculum for students of medicine and other health care professions, and is included in course examinations. Postgraduate doctors may seek training on courses which are organized by the Hygiene Institute of the University of Vienna in co-operation with the Austrian Society of Hygiene, Microbiology and Preventive Medicine. Registered nurses may enroll in the Austrian Nurses' Association training scheme (6 weeks of theory with professional work for 2 years), leading to approval as Hygieneschwester/-pfleger. Postgraduate in-hospital education for all health-care professions occurs in many Austrian hospitals, with resources from Vienna and Linz. Hospital managements, health authorities and politicians are influenced via their own educational activities and via publications.

Austria↗
PubMed1990

Discrimination between antibodies to HIV-1 and HIV-2 in sera from northern Zaire.

136 selected sera from Northern Zaire were screened for antibodies against HIV-1 and HIV-2 using the ELISA method. Reactive sera were confirmed with commercially available Western Blots and additional tests. A data base was used for evaluation of the results. The sera were collected in the town Isiro and in remote rural areas. 36 sera were reactive in the HIV-1 ELISA (ELAVIA-1), 19 of them were confirmed in the HIV-1 Western Blot (Biorad). 21 sera were reactive in the HIV-2 ELISA, but they were not confirmed as HIV-2-specific in three HIV-2 Western Blots (Diagnostics Pasteur, Biorad, Paul-Ehrlich-Institut).

Blotting, Western↗
PubMed1989

[Dental care of HIV carriers].

As HIV infections continue to spread worldwide, the number of patients with known or unknown HIV positivity seen in dental practice is increasing. Some of the infected individuals need more frequent dental care than the general population, because HIV infections tend to be associated with specific oral manifestations. HIV-positive individuals have special psychosocial problems attributable both to their disease and to their frequent association with socially discriminated groups. These problems are also reflected in the dentist-patient relationships. Dental care of known HIV-positive individuals is much less hazardous than the treatment of undiagnosed HIV carriers. Building confidence between the dentist and the patient is essential. As HIV transmission is similar to that of hepatitis B, the full battery of hygienic precautions established for preventing hepatitis B should be observed in dental work to prevent HIV infections. Conditions of work in dental offices should meet the hygienic standards needed to preclude the risk of infections both for the dentists and their patients.

Acquired Immunodeficiency Syndrome↗
PubMed1989

[Monitoring infection at the intensive care unit--a multicenter pilot study].

During a period of 3 months an infection survey was carried out in 4 intensive care units (ICUs), 2 in Vienna, Austria, and one each in Ulm and Münster, Federal Republic of Germany, using a common protocol. A total of 329 patients was monitored prospectively. This pilot study was performed to evaluate the usefulness of parameters included in the monitoring form. It was attempted to characterize the patient populations of the four units. Mean duration of stay (1-12 days), mortality (8-26%), leading diagnosis upon admission, intubation rate (41-91%) and use of pulmonary artery catheter (12-35%) were distinctly different. The rate of patients admitted already with an infection was 9-43%, septicemia was diagnosed in up to 27% of the diseased. The rate of infection acquired in the unit was between 12 and 37%, the most frequent types were bronchopneumonia, septicemia and urinary tract infection. When septicemia patients were compared to non-septicemia patients who had been admitted for more than 3 days, it appeared that the latter stayed significantly shorter at the ICU and showed less frequently bronchopneumonia or urinary tract infection at the time of admission. Septicemia patients acquired more frequently additional infections like broncho-pneumonia or urinary tract infection while staying at the ICU. The median day of onset of septicemia was the fifth day and only in a quarter of cases diagnosis could be supported by a positive blood culture. The use of antibiotics in the 4 ICUs is compared and shows marked differences. Based upon experience with this type of infection survey a new modified protocol is introduced, which displays the time course of documented events.

Anti-Bacterial Agents↗
PubMed1987

Epidemiology of borrelia infections in Austria.

From April 1984 to July 1985 873 cases of Borrelia infections were registered at the Hygiene Institute of the University of Vienna. 2609 serum samples of these patients were investigated for antibodies against B. burgdorferi by means of IFA- and ELISA-tests. Erythema chronicum migrans (ECM) was recognized in 60.9% of patients, neurological abnormalities were recorded in 23.4% of which the majority manifested themselves as polyradiculitis and meningopolyneuritis (MPN). Acrodermatitis chronica atrophicans (ACA) was recognized in 11.5%. A small number of patients suffered from Lymphadenosis cutis benigna (LCB), arthritis and cardiac abnormalities. Sixty percent of patients were females and 40% males. Infections were found in all age groups ranging from 2-83 years in females and 1-85 years in males. Tick- or insect-bites prior to the onset of illness were reported by 47.2% and 15.6% of patients, respectively. The main vector is the hard tick Ixodes ricinus. Flying insects from the family tabanidae, i.e. Chrysops caecutiens and Haematopota species, must also be considered as transmitters. Antibodies to B. burgdorferi were found in 22.3%, 93.6% and 100% of sera from patients with ECM, MPN and ACA, respectively. Six of 11 patients with LCB and all with arthritis and cardiac abnormalities showed serologic reactivity. Geographically, Borrelia infections are distributed in all states of Austria. The seasonal distribution of cases show a peak in July and August, but the onset of clinical manifestation could be observed throughout the year. These results present Austria as an area where tick- or insect-borne Borrelia infections are very frequent and endemic in all Austrian states.

Acrodermatitis↗
PubMed1986

[Hepatitis A outbreak in a shelter for the homeless in Vienna].

An outbreak of hepatitis A was observed in a shelter for the homeless in Vienna with about 200 inhabitants. Twenty-two cases occurred within a period of 6 months. The outbreak could not be brought under control by measures of general hygiene. However, after the administration of hepatitis A immunoglobulin (120 IU/ml), at a dosage of 0.05 ml/kg body weight, to 102 of the 105 seronegative inhabitants and members of staff, no further clinical cases of hepatitis A were reported from this group. Nevertheless, 8 of these 102 "protected" persons showed signs of subclinical infection at subsequent follow up. Apart from these, 2 further cases of hepatitis A occurred among the non-immunised children at risk, whose parents had refused permission for serological investigation or immunoglobulin administration.

Adolescent↗
PubMed1986

Borrelia transfer by ticks during their life cycle. Studies on laboratory animals.

Ticks of the species Ixodes ricinus were cultured in the laboratory. Yellow silver rabbits, gerbils and white mice served as blood hosts. Borrelia burgdorferi could be detected by means of an IFA test in homogenates of female ticks, their eggs as well as the respective larval and nymphal ticks. Blood infection of splenectomized gerbils and ordinary white mice or of ordinary white mice alone has been demonstrated after feeding of larval or nymphal ticks on them, respectively. Spirochetemia started 5 to 8 days after feeding and lasted for ca 3 weeks. Two distinct peaks in the cell count of spirochetal organisms per ml blood plasma could be observed on days 11-13 (5 X 10(5) to 2 X 10(6) cells/ml) and 17-19 (10(5) cells/ml), regardless whether splenectomized gerbils or white mice were used. The results display that B. burgdorferi is vertically from the female ticks to their eggs and transstadially transmitted. The transmission-rate from larval to nymphal ticks is 100%. These findings show the tick itself as a main reservoir of B. burgdorferi. The established mouse-model appears to be a useful tool to detect Borrelia carrying ticks.

Animals↗
PubMed1986

Evaluation of procedures for hygienic hand-disinfection: controlled parallel experiments on the Vienna test model.

Controlled parallel experiments were performed on the Vienna test model for the evaluation of procedures for hygienic hand-disinfection in three laboratories (Vienna, Mainz, Birmingham). The degerming activity of four procedures, each taking 1 min, was assessed repeatedly and compared with that of a standard disinfection procedure (ST) using isopropanol 60% (v/v). The mean log reductions (mean log RF) for each procedure were as follows: n-propanol 50% (v/v) 4.85 and 5.14 in Vienna (V) and Mainz (M) respectively, ethanol 70% (v/v) + chlorhexidine-gluconate 0.5% (w/v), 4.01 (V), 3.76 (M) and 4.00 in Birmingham (B). Washing procedures were less effective, mean log RF's of 3.19 (V), 3.49 (M) and 3.04 (B) were obtained with povidone-iodine soap, and 2.91 (V), 3.37 (M) and 3.27 (B) with a liquid phenolic soap. Analysis of variance on the data from Vienna and Mainz revealed significant differences of means not only between procedures ('preparations') but also on repeat testing. To compensate for the influence of variables such as test subjects, laboratory and day, the Vienna test model provides a method of standardization by testing a ST in parallel with the test procedure (P). Standardization of the results was obtained by pair-wise substraction, log RFPi-log RFSTi. Analysis of variance on the resulting values demonstrated that comparability of the results between laboratories and on repeat testing was achieved. The relative variation of the measurements within the laboratories ranged from 0.9 to 4.2%. As assessed by power-analysis, a disinfection procedure will be detected as significantly (P = 0.1) inferior to the standard processes in 95 of 100 experiments if it produces a mean log RF that is at least 0.55-0.65 log units smaller than that of the standard.

Austria↗