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G Wewalka

Publications and source records attributed to G Wewalka.

51 records · Page 3Linked to original sources

[Testmethod for the evaluation of procedures for the hygienic disinfection of hands. Part 1: Discription of testmethod (author's transl)].

A detailed test design for the evaluation of procedures for the hygienic disinfection of hands is described together with suitable methods for statistical analysis of the results. In principle the release of testbacteria from the finger-tips of artificially contaminated hands is measured before and after disinfection. A procedure under test is accepted if it is not less effective than a standard-disinfection procedure. As such the disinfection with iso-propanol 60% (ml/ml) applied through 1 min was agreed upon. This standard procedure is to be performed the same day with the same day with the same testpersons and under identical environmental conditions prior to the procedure under test.

1-Propanol↗

[Comparison of efficacy of 14 procedures for the hygienic disinfection of hands (author's transl)].

The efficacy of 14 procedures for the hygienic disinfection of hands mostly with commerical preparations was tested by a new experimental model developed at the Institute of Hygiene of the university Vienna (1,3). The disinfectant power was clearly dependent on the duration of treatment as well as on the kind of alcohol used in the preparation (n-Propanol better than iso-Propanol better than Ethanol). After one minute the efficacy of all preparations containing one of the three alcohols as active agent was well comparable to that of the standard procedure which according to our proposal (5) uses iso-Propanol 60% (ml/ml) for 1 minute. For preparations with n-Propanol as the main active agent (Satinazid and Sterillium) this was true even after treatment for a period as short as 0.5 min. In our opinion disinfecting detergents are out of place for hygienic disinfection of hands. One preparation representing this group (Versuchspräparat A) was far less effective than the standard procedure.

1-Propanol↗

[Sensitivity of bacteria causing urinary tract infections towards terizidon (author's transl)].

In agar diffusion tests 2603 bacterial strains of species known to cause urinary tract infections were tested routinely in regard to their sensitivity towards Terizidon, a derivative of cycloserine. In order to relate the results which were obtained in terms of the diameter of the inhibiton zone, to the minimal inhibitory concentrations (MIC), 304 of these strains were tested additionally in agar dilution tests. The MICs of the other strains were estimated from the results of these tests. Since it is known that after the oral administration of 500 mg Terizidon the urine contains, on average, more than 128 mug/ml Terizidon for 12 hours and longer, it may be concluded from the results of this investigation that 75% of the strains of E. coli and Citrobacter, 45% of enterobacter, 40% of Proteus mirabilis and enterococci, 35% of the indole-positive Proteus strains and 30% of Pseudomonas aeruginosa would have been successfully attacked by Terizidon in the case or urinary tract infections. By contrast, Klebsiella must be reagarded as being completely resistant to this antibiotic. It follows that the administration of Terizidon is mainly indicated in the treatment of acute urinary tract infections with E. coli as the predominant causative agent.

Citrobacter↗

[The patient as a source of bacteria in intensive care units: influence of antibiotics and tracheal intubation (author's transl)].

133 patients in an intensive care unit, who prior to admission had not shown any signs of bacterial infection and had not received antibiotic treatment, were assigned to two groups at random. One group received antibiotic prophylaxis with penicillins or cephalosporins (+Pat.), the other group did not receive antibiotics (-Pat.). Staph. aureus was the most frequent facultative pathogen in tracheal secretions and in the environment of "-Pat.". This organism was significantly more frequent in "-Pat." than in "+Pat." in both the tracheal secretions and the environment. Klebsiella spp. outnumbered all other species in "+Pat.". They were significantly more frequent in tracheal secretions of "+Pat." than of "-Pat.". In the first week of hospitalisation marked changes were seen in bacterial flora of tracheal secretions of "+Pat.". Colonization with grammnegative bacteria rose to nearly 100%, the frequency of Staph. aureus diminishing at the same time. Monitoring by contact cultures revealed that gramnegative rods were significantly more numerous in the environment of "+Pat." than of "-Pat.". Matching bacterial strains cultured from tracheal secretions and from the environment of the patients proved that "+Pat. spread significantly higher numbers of their gramnegative bacteria into the environment. The same is true of "-Pat." for Staph. aureus. Intubation had no noticeable effect on the degree of contamination of the surroundings with Staph. aureus. Gramnegative rods were significantly more frequent in tracheal secretions of patients with intubation than in patients without. The same trend was observed for environmental contamination. As the clinical results of this study have shown, antibiotic prophylaxis does not protect patients from infections to the extent expected. Patients, and particularly intubated patients, receiving antibiotic treatment have to be considered as sources of highly resistant gramnegative organisms.

Anti-Bacterial Agents↗

[Kinetics of the release of testbacteria from the artificially contaminated hand (author's transl)].

It is demonstrated that the release of testbacteria from the finger tips of artificially contaminated hands is influenced to a very small degree only by application of the finger tip method when compared to the effect of ablutions. Therefore, without apprehension of influencing the post-values this method may be employed in order to assess pre-values as required by the test-model of Rotter and Mittermayer (5) for the evaluation of procedures for the hygienic disinfection of hands. In addition, it can be shown directly that it is irrelevant for the number of bacteria released after a germ-reducing procedure, whether the finger tip-method has been used or not, preceedingly. In contrast, all technical variations that aim at the restitution of the supposed loss of testbacteria (like renewed contamination after the assessment of prevalues) change the postvalues measurably and must be avoided, therefore. Drying of bacterial suspensions on the hands, as after artificial contamination, reduces the release of viable testbacteria depending on the time. This effect is stronger on the palms than on the finger tips. The influence of handbrushes on the release of testbacteria with simultaneous useage of detergents compares well with the effect of an alcohol disinfection. However, this method is not suitable to eliminate pathogens safely.

Escherichia coli↗

[Early bacteriological diagnosis of infections after osteosynthesis (author's transl)].

Postoperative infections after osteosynthesis belong to the most serious complications in traumatology. Efforts to prevent this danger by routine antibiotic prophylaxis are mainly rejected nowadays. Instead, it is studies whether infections can be diagnosed by bacteriological culture of secretions from Redon drains in patients with osteosynthesis for the purpose of starting an early specific antibiotic therapy. Bacteria were cultured from secretions of wounds in 11.3% of samples from 177 patients. Staph. aureus was found most frequently and was responsible for most of the postoperative infections (Tab. 1).

Anti-Bacterial Agents↗

Six cases of travel-associated Legionnaires' disease in Ischia involving four countries.

The detection of travel-associated legionellosis can be extremely difficult; hence, an extensive case investigation is recommended in pneumonia-striken travellers and tourists, who are particularly at risk of acquiring the disease. On the Island of Ischia (Isola d'Ischia, Naples, Italy) a total of six cases of Legionnaires' disease occurred from 1986 to 1990. All patients (one man and two women from Germany, one Austrian woman, one Swiss man, and one Italian woman) had taken thermal baths and stayed in local hotels; they all experienced severe pneumonia, and three of them died. These cases were associated with hotels, and the hot-water supply was presumed to have transmitted the infection. Remedial procedures were applied to the hot-water plumbing of the hotels according to the WHO recommendations and were proved to be effective. The occurrences described in this paper stress the importance of rapid and accurate reporting of diagnosed cases to the country where the infection was probably acquired, in order to ensure early detection of endemic foci and emerging clusters of legionellosis.

Aged↗

Infant tuberculosis in Austria--trend reversal since 1990?

Since 1990 a relatively high number of cases of childhood tuberculosis has been observed in Austria, mainly occurring in the age-group of 0-4 years. Within this group most cases were registered in 1995. Since the beginning of 1995 the establishment of a lab-supported nationwide data collection system enables a more detailed recording of the cases diagnosed. Out of the 85 cases with infant tuberculosis registered in 1995 and 1996, 66 were diagnosed with pulmonary manifestation. In 45 cases tuberculosis was proven by culture. In nine (20%) of these cases the most likely route of infection has appeared to be direct transmission from an adult in the same household suffering from culture proven tuberculosis in the same year. For three of the cases the DNA of the isolated Mycobacterium tuberculosis strains from the adult and the infant was typed using RFLP analysis. In each case identical strains could be demonstrated.

Austria↗