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Remote interpretation of microbiology specimens based on transmitted still images.

A pilot study was carried out to examine the feasibility of the remote interpretation of microbiology specimens, that is, micro-organisms grown on agar in Petri dishes. The objective of our study was to decide whether still images contained enough information for microbiology specialists to identify the microorganisms accurately. A representative sample of microbiology specimens grown on the most commonly used agar media was used. Still images were captured using a video camera and a PC-based system. The results from a pilot study with the first video camera were discouraging, the interpretations differing in five out of 22 specimens; results with a second video camera were also disappointing. Images were then captured on photographic film, at a considerably higher resolution than images captured by the digitizer board in the PC. Again, however, the results were disappointing. We conclude that interpretation of microbiology specimens based exclusively on visual information is problematical. Remote microbiology interpretation in the future will require images of higher information content (e.g., including three-dimensional information), and will probably require additional information as well, from other senses, such as smell.

Bacteria↗

The microbiological quality of cooked rice from restaurants and take-away premises in the United Kingdom.

The microbiological quality of 4,162 samples of cooked rice from restaurants and take-away premises in the United Kingdom was examined, including ready-to-eat rice purchased at point-of-sale and rice that was stored precooked for reheating on demand. The majority of point-of-sale cooked rice samples (1,855 of 1,972; 94%) were of acceptable microbiological quality, but 15 (1%) samples were of unacceptable quality (Bacillus spp. and B. cereus, > or = 10(5) CFU/g; Escherichia coli, > or = 10(4) CFU/g), indicating a potential risk to health. The prevalence of Bacillus spp., B. cereus, and E. coli was significantly greater in precooked stored rice than in point-of-sale cooked rice (P < 0.005 to 0.0005). Bacillus spp. (> or = 10(4) CFU/g), B. cereus (> or = 10(4) CFU/g), and E. coli (> or = 10(2) CFU/g) were present in 7%, 2%, and 9% of precooked stored samples, respectively, compared to 2%, 0.5%, and 1%, respectively in point-of-sale samples. Although final heating at the point of sale reduces the levels of microorganisms present in rice it will not inactivate the B. cereus emetic toxin if present. Rice from Indian premises was of poorer microbiological quality than that from Chinese and other premises. Although most point-of-sale cooked rice samples (94%) were of an acceptable microbiological quality, evidence from this study indicates that the microbiological quality of cooked rice sold from certain outlets in the UK is of concern.

Bacillus↗

Microbiological study of ready-to-eat salad vegetables from retail establishments uncovers a national outbreak of salmonellosis.

The increasing availability of bagged prepared salad vegetables reflects consumer demand for fresh, healthy, convenient, and additive-free foods that are safe and nutritious. During May and June 2001 a study of retail bagged prepared ready-to-eat salad vegetables was undertaken to determine the microbiological quality of these vegetables. Examination of the salad vegetables revealed that the vast majority (3,826 of 3,852 samples; 99.3%) were of satisfactory or acceptable microbiological quality according to Public Health Laboratory Service microbiological guidelines, while 20 (0.5%) samples were of unsatisfactory microbiological quality. Unsatisfactory quality was due to Escherichia coli and Listeria spp. (not Listeria monocytogenes) levels in excess of 10(2) CFU/g. However, six (0.2%) samples were of unacceptable microbiological quality because of the presence of Salmonella (Salmonella Newport PT33 [one sample], Salmonella Umbilo [three samples], and Salmonella Durban [one sample]) or because of a L. monocytogenes level of 660 CFU/g, which indicates a health risk. In each case, the retailer involved and the UK Food Standards Agency were immediately informed, and full investigations were undertaken. Nineteen cases of Salmonella Newport PT33 infection were subsequently identified throughout England and Wales. The outbreak strain of Salmonella Newport PT33 isolated from the salad and from humans had a unique plasmid profile. Campylobacter spp. and E. coli O157 were not detected in any of the samples examined. The presence of Salmonella, as well as high levels of L. monocytogenes, is unacceptable. However, minimally processed cut and packaged salad is exposed to a range of conditions during growth, harvest, preparation, and distribution, and it is possible that these conditions may increase the potential for microbial contamination, highlighting the necessity for the implementation of good hygiene practices from farm to fork to prevent contamination and/or bacterial growth in these salad products.

Colony Count, Microbial↗

Microbiological quality of open ready-to-eat salad vegetables: effectiveness of food hygiene training of management.

During September and October 2001, a microbiological study of open, ready-to-eat, prepared salad vegetables from catering or retail premises was undertaken to determine their microbiological quality. The study focused on those salad vegetables that were unwrapped and handled either by staff or customers in the premises where the sample was taken. Examination of salad vegetables from food service areas and customer self-service bars revealed that most (97%; 2,862 of 2,950) were of satisfactory or acceptable microbiological quality, 3% (87) were of unsatisfactory microbiological quality because of Escherichia coli levels in the range of 10(2) to 10(5) colony-forming units per gram. One (<1%) sample was of unacceptable microbiological quality because of the presence of Listeria monocytogenes at 840 colony-forming units per gram. The pathogens E. coli O157, Campylobacter spp., and salmonellas were not detected in any of the samples examined. The display area for most food service and preparation areas (95%) and self-service salad bars (98%) that were visited was judged to be visibly clean by the sampling officer. Most self-service bars (87%) were regularly supervised or inspected by staff during opening hours, and designated serving utensils were used in most salad bars (92%) but in only a minority of food service areas (35%). A hazard analysis system was in place in most (80%) premises, and in 61%, it was documented. Most (90%) managers had received food hygiene training. A direct relationship was shown between increased confidence in the food business management and the presence of food safety procedures and the training of management in food hygiene.

Colony Count, Microbial↗

[Electronic data processing in medical microbiology--a guide and some critical thoughts].

Applications of electron data processing in all fields of medicine and especially in medical microbiology are increasing rapidly. It seems important to discuss a guide for using such complicated electronical systems, because, on the one hand, computer applications in medicine are desirable for scientific reasons, but on the other hand few very costly and sophisticated projects had to be cancelled, after a shorter or longer time of implementation by reason of lack of co-operation of medical collaborators. This paper puts on discussion such a guide for using electronic data processing in medical microbiology. It is proposed to put through the following tasks before introducing a computer system into a microbiological institution: a system analysis of the status quo, an objective determination of the set state, a system design and a cost-benefit analysis. Those tasks are described in detail and are illustrated to some extent by graphics and tables from own research for preparing a data processing system for medical microbiology. It is emphasized that beside hard- and software criteria of the desired computer system one has to pay attention to the problems of man-machine engineering. The paper finishes with concrete propositions of proceeding when the computer system is implemented and shows possibilities of scientific data evaluation of a microbiological data base.

Costs and Cost Analysis↗

Microbiological standards for water and their relationship to health risk.

Maintenance of the microbiological quality of water has been used as an important means of preventing waterborne disease throughout the twentieth century. The commonest microbiological tests done on water are for coliforms and Escherichia coli (or faecal coliform). This paper reviews the legislative and other guidance for microbial standards in drinking and bathing waters and considers evidence for the relationship between the microbiological quality of water and risk to human health. In the past measures of the microbiological quality of water correlated well with risks of acquiring gastrointestinal disease. More recent work suggests that gastrointestinal disease is more strongly associated with the presence of enterococci than of E. coli. New diseases such as cryptosporidiosis have been shown to cause outbreaks of waterborne disease when levels of conventional microbiological parameters are satisfactory. In response to this, and because of failure of prosecution in one outbreak, the United Kingdom (UK) Government has introduced new legislation that requires water providers to perform a risk assessment on their water treatment facilities and to implement continuous monitoring for cryptosporidium. A new European directive on drinking water has been introduced and legislation on cryptosporidium in drinking water has been proposed in the UK.

Animals↗

[Sampling plans in microbiological criteria for food and their "performance criteria"].

Statistically based acceptance sampling plans have been integrated into microbiological criteria for food in international trade for some time. Especially two- and three-class sampling plans for attributes are used, variables plans are applied less. A lot of examples can be found in the so-called ICMSF (International Commission on Microbiological Specifications for Foods) "sampling book" or in EU guidelines. However, quite often the required confidence and the assumptions on tolerable lot qualities on which the choice and design of sampling plans are based can't be deduced from such recommendations and prescriptions. These problems have led to critical discussion of the performance of two- and three-class sampling plans used in microbiological criteria, showing complex dependencies on microbiological limits and on the expected variability of sampling results. As a result means should be considered to use knowledge gained from process analyses in food production in the design of sampling plans. In this context the performance of acceptance sampling plans as prescribed in microbiological criteria for foods will be discussed as well as their role in recently developed food safety concepts.

Animals↗

[Optimizing microbiological controls of corneal organ culture media].

BACKGROUND/AIMS: To compare the efficiency of an automated method using blood bottles with conventional microbiological tests for controlling sterility in cornea organ culture media. METHODS: Two complementary studies were conducted. Experimental study: standard organ culture media were contaminated with four different inocula of 14 bacteria and 3 fungi. The bactericidal activity of organ culture media were evaluated after 48 hours of incubation at 31C. Observational study: 357 samples of organ culture media were collected over 1 year in our cornea bank. For both studies, media were inoculated in three blood bottles (aerobic, anaerobic, fungal) placed in an automat with automated detection every 10 minutes, and in three conventional microbiological media as a control. Changes in organ culture medium color and growth on conventional broth were checked daily by visual inspection. All samples were observed experimentally for 14 days. The sensitivity and rapidity of contamination detection were compared across the three methods: blood bottles, conventional method, and visual inspection of medium color. RESULTS: Experimental study: organ culture medium eradicated five bacteria: S. pneumoniae, B. catarrhalis, E. coli, P. acnes and H. influenzae. For the others, (Methicillin-resistant S. aureus, Methicillin-sensitive S. aureus, S. epidermidis, S. haemolyticus, P. aeruginosa, A. baumannii, B. subtilis, K. pneumoniae, E. faecalis, C. albicans, C. kruzei, A. fumigatus) the blood bottle method, the conventional microbiological method, and the visual inspection detected microbiological growth respectively in 100%, 76.5%, and 70% of cases. Mean detection time using blood bottles was 15.1 hours (standard deviation, 13.8; range, 2-52). In cases of detection by the blood-bottle method and the conventional method, the former was always faster: 95.5% versus 65.2% detection within 24 hours (p=0.022). Observational study: the global contamination rate was 8% (29/357 analysis). The gain in sensitivity with blood bottles was 25% compared with the conventional method. Five bacteria (three coag. neg Staphylococcus, one E. faecalis, one P. paucimobilis) were detected only by the blood bottles. In addition, these were always detected more quickly with, respectively, 66.6% versus 26.6% detection with 24 hours (p=0.028). CONCLUSIONS: Blood bottles detect contaminations of cornea organ culture media more efficiently and faster than conventional microbiological methods. They make it possible to reduce the quarantine period with an equally high security level. Consequently, they should be recommended in cornea preservation guidelines.

Bacteria↗

[Harmonization of microbiological food safety requirements: problem statement and modern problems].

In work the analysis of the factors influencing levels of microbiological specifications is given. The system of microbiological standardization and the food safety control in the developed countries is characterized. The Russian system differences and specificity of the factors causing microbiological quality of a domestic production are analyzed. The history of a question and modern tasks of harmonization of domestic specifications with the microbiological standards accepted in the international practice are described. Drew conclusions: (1) existing distinctions depend on a difference in an economic situation and in conditions in which manufacture and consumption of foods is carried out, (2) according to experience of the developed countries, for updating and harmonization of microbiological specifications at the first stage are necessary measures of the economic and organizational order for creation of comparable conditions of manufacture, and also a designation of real terms for introduction of harmonized specifications at an official level.

Consumer Product Safety↗

Microbiology teaching in American dental schools.

A comprehensive questionnaire on current practices relevant to teaching microbiology to dental students was sent to all dental schools in the United States. The survey collected information on resources available, modes of teaching, and evaluation processes. Seventy percent (42/60) of the schools responded. Great variation was found in the teaching of microbiology largely due to the variety of educational resources, perspective of subject matter by the faculty, and the backgrounds of entering students. Data are presented that document the integration of microbiology with other courses, placement of microbiology in the curriculum, class attendance policies, availability of advanced selective and/or elective courses, and National Board reviews. These and other data indicate some prevailing trends in the teaching of microbiology to dental students.

Curriculum↗

[Microflora of grain in the cleaning and milling process. 7. Modification of the microbiologic and health quality of grain by product separation].

Food cereals and food cereal products which are consumed directly (without any heart treatment in order to reduce their microflora) should fulfil certain criteria with regard to their microbiological hygienic condition. It can be proved that the microflora of a given cereal batch is differently destributed according to the kernel volumes. Small and light kernels have more microorganisms than heavy kernels. By the separation of certain amount of light kernels (about 15%) from a batch the microbiological condition of the remainder of the batch can be improved. Any separation procedure seizes definite "Besatz" fractions and takes therefore different influence on the microbiological condition of the obtaining cereal fraction, therefore the microbiological condition of the cleaned cereal fraction can be differently affected by the cleaning method. A suitable method for preparation of food cereals is a diagram consisting of: aspirator, light kernels separator, stoner and magnetic separator. In order to get milling products with reduced microbiological germ content the sorting of product can be applied.

Edible Grain↗

[Problems of maintaining of hygienic and microbiological quality standards of foodstuffs, particularly of vegetable origin (author's transl)].

As more and more components of our food are nowadays subjected to industrial processing, microbiological controls of raw materials and plant hygiene are important factors in protecting the consumer. In many cases preventive measures and specifications of microbiological characteristics of certain foodstuffs governed by legal regulations do not suffice to guarantee protection of the consumer as desired. For this reason conscientious food manufacturers maintain controls in line with self-imposed and very strict hygienic and microbiological rules. Insufficiencies of the relevant dietetic regulations are exposed and measures to ensure quality recommended. It is shown that, to determine the hygienic and microbiological condition of dehydrated vegetable raw materials, the conditions applying to fresh vegetables must be taken into consideration. Peculiarities pertaining to the microbiological examination of seasonings and methodical problems of determining and judging the spore contents in foods are described.

Bacteriological Techniques↗

[Current state and problems in the microbiology laboratory--organizing the laboratory].

The microbiological laboratory in the hospital has many roles including the rapid and precise identification of pathogenic bacteria in specimens, their antimicrobial susceptibility tests, microbial antigen detection using immunological methods and DNA hybridization methods, surveillance of bacterial milieu of the hospital environment, monitoring quality control of microbiological methods, to educate microbiological skills of staffs, the economical management of laboratory and so on. The last two issues are our major concerns. Improvement of the microbiological skills of the staff is most important in the laboratory, but is a time-consuming. From our experience, a technical expert, intermediately skilled technicians and beginners should always work in the laboratory, together. On the other hand, the economical management of the microbiological laboratory is also another concern. Although the mechanization of procedures comes to mind, it is hard to improve the economical conditions in the laboratory. Because of the control of the machines is not completely automatic and requires the knowledges and decisions of technical experts, the work force and running cost can not be reduced. As the technical expert can economize in the use of media or tests for identification of pathogens, good training of beginners into skillful successors, is important.

Humans↗

[Usefulness of microbiological test in clinical decision making--from the view point of clinician].

During the last 50 years, there have been changes in the types of infectious diseases causing death in Japan. Endemic diseases have decreased and nosocomial infection during the therapeutic course of various diseases have increased. Progress of various new medical technology for cancer therapy and transplantation are supported by developed infection control, and the target of microbiological tests has changed from endemic organisms to resident organisms. To manage infectious diseases, clinicians collect considerable information. Microbiological tests are only one part and sometimes are used to assess therapeutic results. In this situation, microbiological tests sometimes only reconfirm or guide changes in therapeutic strategy if the initial empiric therapy was inappropriate. Then, well designed statistical data are necessary for appropriate empiric therapy. Surveillance of hospital infection is another important role of the microbiological laboratory. To improve the functioning of the microbiological laboratory, we need not only automatic and rapid systems, but also effective communication with clinicians to respond to their needs with clinically useful data.

Humans↗

Comparison of liquid chromatographic method to AOAC microbiological method for determination of L-tryptophan in tablets and capsules.

A reversed-phase liquid chromatographic (LC) method coupled with precolumn derivatization of L-tryptophan with phenylisothiocyanate was compared to the AOAC microbiological method for determining L-tryptophan in tablets and capsules. For the microbiological method, the concentrations of L-tryptophan were 4-8% lower in autoclaved test samples (hot method) than in test samples that were not autoclaved (cold method). When L-tryptophan values obtained by the LC method were compared to those obtained by the cold microbiological method, no significant differences were observed (P > 0.05). The mean relative standard deviations were 2.9% for the LC method and 1.6% for the cold microbiological method. The mean recoveries of standard L-tryptophan added before analysis were 99% for the LC method and 101% for the cold microbiological method. These results demonstrate that both methods are reliable for determining free L-tryptophan contained in tablets and capsules. However, the LC method has the advantages of using a smaller test portion and having a shorter analysis time.

Capsules↗

[Microbiological condition of bottled natural mineral waters, drinking water, as well as water from mineral springs].

We are now in the midst of a critical discussion on the microbiological quality of bottled natural mineral water, springwater, so-called "table water" and drinking water. "Still" waters have high colony counts after long storage, whereas in carbonated bottled products multiplication of oligocarbophilic microorganisms is suppressed by carbon dioxide. Opportunistic species are also found in bottled water. Present knowledge as to whether they are contaminants or part of autochthonous flora is insufficient. Highly colonised foodstuffs and opportunistic species may be hazardous for immunosuppressed patients. Hence, it is claimed that existing legal microbiological criteria for bottled water are inadequate. High colony counts in foodstuffs do not necessarily imply poor microbiological quality a priori. Detection of an opportunist species does not justify classifying a food item as hazardous. Microbiological criteria for bottled water which are laid down in the Directive for Mineral and Table Water of the German Food Legislation Act (LMBG) were established based on recommendations by international microbiologists for the normal not oversensitive consumer. For more sensitive groups of consumers, for example babies, more severe criteria were set up. Immunosuppressed patients are another sensitive group, demanding special hygienic requirements for their surroundings. If the risk of infections for immunosuppressed patients cannot be reduced by other means, it might be useful to establish microbiological criteria for bottled water and of course for other foodstuffs as well. However, such criteria cannot be adequately applied to food for normal consumption, since otherwise many foods would have to be regarded as hazardous and could not be marketed because of legal prescriptions.

Drinking↗

[Microbiologic diagnosis of community-acquired pneumonia in adults].

Microbiological analysis allows us to identify the etiology of pneumonia and its in vitro susceptibility pattern. Antibiotic treatment directed against a known pathogen enables us to narrow antibacterial spectrum of action, and to reduce costs, drug adverse effects risk and antibiotic resistance. However it is unnecessary to perform extended microbiological studies in all patients with community acquired pneumonia (CAP). Etiological studies must be based in pneumonia severity, epidemiological risk factors and clinical response to empirical treatment. Routine microbiological analysis for ambulatory patients is not recommended. In patients with persistent cough and worsening in their general conditions, a sputum sample must be obtained to perform an acid-fast smear and Mycobacterium culture. The risk of complications and death of patients hospitalized with CAP justifies basic microbiological exploration (sputum Gram staining and culture, blood cultures, pleural fluid culture) intending to obtain a more accurate etiology of pulmonary infection and to guide specific antibiotic treatment. Paired serum samples obtained to document atypical pathogen infections (Mycoplasma pneumoniae, Chlamydia pneumoniae) and urine sample to detect Legionella pneumophila antigenuria are recommended in all CAP severely ill patients that are admitted to ICU, in those not responding to betalactamic drug treatment and in selected patients with specific epidemiological risks. A microbiological study would be useful in management of patients with severe CAP pneumonia outbreaks with clinical-epidemiological particular characteristics, and in-patients with empirical antimicrobial treatment failure.

Adult↗

Effect of gallium arsenide diode laser on human periodontal disease: a microbiological and clinical study.

BACKGROUND AND OBJECTIVE: The present study is aimed to describe short-term results on selected microbiological and clinical parameters obtained by treatment with soft laser in conjunction with methylene blue and/or mechanical subgingival debridement in human periodontal disease. STUDY DESIGN/MATERIALS AND METHODS: Ten patients, in whom each dental quadrant was randomly designated to receive one of four types of treatment procedures, were included in the study. Groups of quadrants received: scaling/root planing (SRP); laser application (L); SRP combined with L (SRP/L); oral hygiene instructions (OHI). Four single rooted teeth (one in each quadrant), having an interproximal site with a probing depth of 4 mm mesio-buccally, were selected in each patient. The selected teeth were first assessed for microbiological (one site/tooth) and then for clinical variables (six sites/tooth). Supragingival irrigation with methylene blue was performed prior to laser application. The microbiological (proportions of obligate anaerobes) and clinical measurements (plaque and gingival indices, bleeding on probing, probing pocket depth) were evaluated over a period of 32 days. RESULTS: Only the SRP/L and SRP groups provided significant reductions in the proportions of obligate anaerobes before and after treatments with no significant differences in between. Parallel to the microbiological changes, both SRP/L and SRP resulted in similar clinical improvements, whereas L alone revealed a limited effect similar to OHI. CONCLUSION: Within the limits of this study, methylene blue/soft laser therapy provided no additional microbiological and clinical benefits over conventional mechanical debridement.

Arsenicals↗