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J Borneff

Publications and source records attributed to J Borneff.

At least 19 recordsLinked to original sources

[Efficient hygiene precautions in the household today].

The results of epidemiological investigations justifies the assumption that increasing health defects, especially enteritis infectiosa, are caused inter alia by inadequate hygienic conditions in households. The number of such diseases ranges between 100,000 and more than 1,000,000 cases per year in the FRG. Responsible for this development is a lack of information about the behaviour of microorganisms in the environment and its pathways of distribution. In addition risks are growing with the recommendation of cleansing methods, which had been adequate for the kitchen techniques in former centuries, but must fall under the conditions of the modern supply, processing and conservation. The described investigations are directed at the determination of the distribution of germs by working in normal household kitchens and at the effectiveness of surface-decontamination-cleansers (so-called FD-preparations). Test principle was the production of a complete dinner by each of 79 housewives with use of minced meat, which was contaminated with micrococcus luteus. After final cleaning of the kitchen we determined the degree of contamination of surfaces, machines and of the components of the meal with use of rodacplates, swabs and quantitative cultures respectively. The experiments are completed by interviews with the housewives. The results let conclude that the use of household cleansers with germicidal properties even in the hand of housewives will reduce the distribution of unwanted microorganisms in the kitchens. In this respect surfaces, on which components of the meal are prepared, and the machines, like cutting machines, waring blenders a.o., are of utmost importance. Disinfections of other parts of the flats including toilets are unnecessary (exception: severe infectious diseases). Therefore the use of FD-preparations outside of the kitchens is not required, but acceptable (it is not necessary to use a cleanser in the kitchen, another one in the toilet and a third one for the bath tube etc.). We do not recommend adapting cleaning and disinfective methods of the hospitals to the normal households. Instead of medical disinfections one should use detergents with nontoxic germicidal additives (e.g. H2O2) in this area, which do not require changing the traditional cleaning techniques. They also should guarantee that cleanliness, absence of odor and minimization of germs are achieved. In addition normal kitchen soaps should be replaced by HD-preparations.

Communicable Disease Control

[Microbiological research methods of drinking water regulation in West Germany from 1986. Suitability of the specifications of DIN 38411, Part 7, for the detection of sulfite-reducing, spore-forming anaerobes (Clostridia)].

The drinking-water regulations of the Federal Republic of Germany, from 22.05.1986, contains in paragraph 1 the instructions: "Drinking-water must be free of pathogens", and further in paragraph 11, "Responsibilities of the employer or other owner of a water supplying facility", include that: "The official authority may direct, that the employer...of a water supplying facility has to extend or has to cause to extend the microbiological examinations in order to determine, that...sulfite-reducing, spore-forming anaerobes (Clostridia) can not be detected in 20 ml of water..." The drinking-water regulations do not prescribe a bacteriological examination method in detail. Appendix 1 rules only that the examination for sulfite-reducing, spore-forming anaerobes (Clostridia) has to be performed after heating the sample to 75 degrees C (+/- 5 degrees C) for 10 min, by either the multiple-tube or membrane filtration method and cultivation in DRCM1-medium. If growth occurs, the presence of Clostridia must be confirmed by anaerobic and aerobic subcultivation. Furthermore, a DIN-instruction (DIN 38411, part 7) exists, which prescribes a detailed procedure for multiple-tube and membrane filtration methods, but does not provide for strict anaerobiosis. We were, however, unable to detect Clostridia in a multitude of water samples with the methods of the DIN-regulation. In order to examine if neglect of strict anaerobiosis was the reason for these failures, we checked the suitability of the DIN-regulation for the isolation of Clostridia from drinking water. In preliminary tests we examined up to four strains of the species C. botulinum, C. cadaveris, C. cochlearium, C. difficile, C. innocuum, C. perfringens and C. tertium for their ability to form heat-resistent spores in four sporulation media. It was, however, not possible to find a medium, in which all strains could sporulate within one week. In order to characterize the detection of these anaerobes in water, one particularly well-sporulating strain of each of the following, C. cadaveris, C. difficile and C. perfringens, was selected and the multiple-tube and membrane-filtration methods were compared. Counts of C. difficile and C. perfringens detected by the multiple-tube method were identical with counts of test-suspensions determinded by the most probable number (MPN) method. It was found to be decisive that only freshly prepared DRCM-medium be used and that, disagreeing with the DIN-instruction, cultivation at 37 degrees C is continued for at least four days.(ABSTRACT TRUNCATED AT 400 WORDS)

Clostridium

[The distribution of microorganisms in household kitchens. I. Problems, experiments, results].

Epidemiological investigations have demonstrated that insufficient hygiene in households results in increasing health hazards. In order to be able to recommend ways to disrupt infection chains it was necessary to explore the most important pathways of cross-contamination. Housewives without special training were instructed to prepare a complete meal, in the kitchen of a modern, vacant apartment. Among the raw products provided was minced meat, contaminated with Sarcinae (unbeknown to the housewives) in a quantitative manner. When cooking and cleaning procedures were completed we analysed household utensils and surfaces by Rodac impressions and swabs. The test organisms could be detected on all inspected surfaces and on the dining-table with albeit different frequencies. The following locations showed an especially high degree of cross-contamination: a) working-surfaces, especially boards of wood and plastics. b) cutting-machines, c) kitchen-machines. These results agree with literature data. By careful disinfection, i.e. by application of a 0.5% solution of hypochlorite, the contaminations could be removed. We assessed this when arranging the kitchen for the next test. Since it is impossible to practise disinfection procedures in a household kitchen on the same scale as in an operating room, we tried to achieve at least a limited disinfection by household cleansers with germicidal properties. In our opinion a minimum reduction of five log stages, demanded in the medical area, can not be achieved in a household kitchen and indeed it is not necessary. A reduction of the microbial counts to 10% of the original value would already be useful, as toxic levels of microbial counts will be reached later especially when there is simultaneous refrigeration. Correct dosage proved to be one of the main practical problems because a discrepancy exists between the low concentration of tensids, necessary for cleaning, and the relatively high dose necessary for germ-killing compounds. Diluted DOMESTOS proved to be a cleaning agent and germicide, but was, however, blamed for chlorine odour, especially when diluted with warm water. A greater acceptance level was reached with a peroxide-containing cleanser, which, however, was not sufficiently germicidal, when applied in diluted form. The concentrated formulation was more effective in everyday experience, but for this housewives had to wear rubber gloves. This was reported to be complicated and uncomfortable, and indeed the search for better formulations must be continued. (In communication II comparisons with the bibliography and hygienic consequences will be published.)

Cooking and Eating Utensils

[The distribution of microorganisms in household kitchens. II. Evaluation of results and hygienic inferences].

The very high morbidity rates of Enteritis infectiosa diseases demand improved prophylactic measures. An important indication of the source of these illnesses is the fact that infections in private households are about three times more frequent than in canteens. Indeed, the rise in morbidity is undoubtedly caused by inadequate treatment of raw products, of meal rests and by insufficient heating processes. Furthermore, in household kitchens no efforts are made to interrupt infection chains, and disinfections are considered as superfluous and housewives are content if their kitchens appear to be clean. The aim of our study performed in a normal household kitchen, was to investigate cross-contamination caused by pathogens, introduced into the kitchen from outdoors. A further aim was to establish the main sources of contamination in order to be able to recommend practical disinfection procedures. The main fields of contamination discovered when 55 meals prepared were: a) working surfaces (including boards of wood and plastics) b) kitchen- and cutting-machines. The amount of test organisms (Sarcinae), introduced into the kitchen (unbeknown to the housewives) by experimentally contaminated minced meat was only reduced by common cleaning procedures, in sofar as nearly half of the original contaminations could be demonstrated to be still present. However, when the normal cleanser was replaced by one containing hypochlorite, and with retention of the same working routines, about 90% bacteriologically clean surfaces were determined. In this way it could be demonstrated that infection chains can be interrupted. It is, however, not correct to compare the efficiency of these procedures with the efficiency of disinfection, according to the Federal Infectious Diseases Act (Bundesseuchengesetz). On practical application of these experiences it must be borne in mind that housewives should not be forced to apply medical disinfection procedures: indeed, traditional and practised cleaning methods should be retained, as far as possible. We recommend therefore that manufacturers supply household cleansers with an anti-bacterial additive, after its application in the kitchens working surfaces and machines are bacteriologically clean. Additionally housewives should be appropriately informed about the necessity of these manipulations. We consider minimization of toxicity and a thorough environmental compatibility of formulations to be self-evident.

Cooking and Eating Utensils

[Occurrence of enteritis-causing agents in private households--a pilot study].

The increasing occurrence of infectious enteritis caused us to perform a prospective, epidemiological pilotstudy in households, in order to receive informations about the practicability of such a project and the bacteriology of food prepared at home as well. 10 families were asked to gather samples of all foodstuffs consumed during the day in separate containers and to keep them frozen at - 20 degrees C until collected by us once a week. Thus we received 4.683 samples within a 6-months-period. In the laboratory those samples were mixed following Table 2 and examined concerning the occurrence of enteropathogenic bacteria. Additionally we carried out an investigation of kitchensurfaces and -utensils by means of "Rodac"-plates. The evaluation of the food-samples showed no growth of salmonella, shigella, yersinia or campylobacter; however, in 267 samples were found staphylococci, in 191 enterococci, in 388 enterobacteria, in 28 aerobic sporeformers and in 144 fungi. Mainly sausage- and meatproducts appeared to be contaminated by staphylococci, also enterococci and enterobacteria (Fig. 1); other groceries were colonized by these microorganisms only to a minor degree. Fungi and aerobic sporeformers were isolated primarily in salads, bakery- and milkproducts (Fig. 2). Though some of the foodstuffs contained up to 10(5) pathogenes/g (Fig. 5), no cases of gastroenteritis were observed within our families. In case of mishandling (e.g. storage of food in refrigerators with temperatures above 4 degrees C) the development of foodborne enteritis has to be taken into account. The kitchens' examination showed a relatively high degree of contamination with pathogenic resp. potentially pathogenic organisms, represented in Fig. 7 by data obtained from different objects of investigation (surfaces, sinks and cloths).

Bacillus cereus

A collaborative study on a new quantitative suspension test, the in vitro test, for the evaluation of the bactericidal activity of chemical disinfectants.

In a collaborative study on a new quantitative suspension test for the evaluation of the bactericidal activity of chemical disinfectants, three laboratories performed the in vitro test on a phenol and an aldehyde standard in the critical use dilutions using Staphylococcus aureus and Pseudomonas aeruginosa as test organisms. The most striking finding was that the means of the germidical effect of one laboratory were significant lower than those of both others. Nevertheless the dispersion of the results did not differ among the laboratories. The differences could not be attributed to the subculture technique followed, nor to the daily inconstancy of the bacterial suspension resistance. The only feature that could explain the difference was the assessment of the microbiological work in itself. It should be stated, however, that the variance of the germicidal-effect values were rather low for this kind of microbiological work, so that differences between laboratories were significant even if the absolute values differed less than 1 unit.

Aldehydes

[Development of a new testmethod for surface disinfection procedures. VII. Proposal for the method (author's transl)].

Based on the findings obtained from the previous experiments (information I-VI), a proposal is made for the examination of surface disinfection procedures under conditions roughly resembling those prevailing in practice. This test allows the action of the disinfectant to be calculated, while making due allowance for the natural rate of kill. The results of three tests with a liminally effective disinfectant concentration extensively agreed with each other. This permits the conclusion that the method has reached optimal standardization.

Candida albicans