The behaviour of Escherichia coli and Pseudomonas aeruginosa in bottled mineral water

Microbial contamination of bottled water during the filling and capping procedure is a problem which should be avoided. The examination of the influence of carbon dioxide (CO2) on bacterial growth of Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) in bottled mineral water was the aim of this study. Commercially available glass bottles with plastic screw caps filled with natural mineral water (without additional CO2 "still" (StMW) and with CO2 "sparkling" (SpMW) were obtained from a manufacturer in the province of Styria, Austria. The artificial contamination was performed in the lab by opening the bottle with subsequent addition of a bacterial solution with a defined number of bacteria. For each bacterial strain, 12 bottles were prepared. Samples (100 mL) were taken after a specific number of days, filtrated and placed on Endo Agar for cultivation. After incubation for 24 h bacterial colonies were counted. In this study CO2 addition to bottled water reduced colony forming units of the two investigated bacterial strains over time.

Background concentrations of airborne, culturable fungi and dust particles in urban, rural and mountain regions

Geographic location and meteorological factors can affect the content of bioaerosol concentrations. This study was conducted to determine the natural background concentrations of culturable fungal spores and dust particles in three different geographical areas. Focus was given to the dominant airborne genera Cladosporium, Penicillium, Aspergillus and the species Aspergillus fumigatus. The influence of weather conditions on the microorganism concentrations in urban, rural and mountain regions were examined. Possible correlations between particle counts and culturable fungal spore concentrations were investigated. 125 measurements of the air were conducted using the air sampler MAS-100NT® and the particle counter Alphasense OPC-N3. The analyses of the collected samples were based on culture methods using different media. The highest median of fungal spore concentrations was detected in the urban region and was of 2.0 × 10³ CFU/m³ for xerophilic fungi and 1.7 × 10³ CFU/m³ for the genus Cladosporium. The concentrations of fine and coarse particles in rural and urban regions were the highest of 1.9 × 10⁷ pa/m³ and 1.3 × 10⁷ pa/m³, respectively. Little cloud cover and slight wind had a positive influence on the concentration of fungal spores. Furthermore, correlations were observed between air temperature and the concentrations of xerophilic fungi as well as the genera Cladosporium. In contrast, relative humidity correlated negatively with total fungi and Cladosporium and no correlation was found with the other fungi. For the region of Styria in summer and early autumn, the natural background concentration for xerophilic fungi ranged between 3.5 × 10² and 4.7 × 10³ CFU/m³ air. No significant differences were detected between the fungal spore concentrations in urban, rural and mountainous regions. The data of this study could be used as a reference to compare the natural background concentrations of airborne culturable fungi in further studies concerning air quality assessment.

Dissolved Carbon Dioxide: The Lifespan of Staphylococcus aureus and Enterococcus faecalis in Bottled Carbonated Mineral Water

During the process of mineral water production, many possible contamination settings can influence the quality of bottled water. Microbial contamination can originate from different sources, for example, the ambient air, the bottles, the caps, and from the bottling machine itself. The aim of this study was to investigate the influence of three different carbon dioxide (CO2) concentrations (3.0 g/L, 5.5 g/L, and 7.0 g/L; 20 bottles each) in bottled mineral water on the bacterial growth of Staphylococcus aureus (S. aureus) and Enterococcus faecalis (Ent. faecalis). The examined mineral water was artificially contaminated before capping the bottles inside the factory. After a specific number of days, water samples were taken from freshly opened bottles and after filtration (100 mL), filters were placed on Columbia Agar with 5% Sheep blood to cultivate S. aureus and Slanetz and Bartley Agar to cultivate Ent. faecalis. The respective colony-forming units (CFU) were counted after incubation times ranging from 24 to 120 h. Colony-forming units of S. aureus were not detectable after the 16th and 27th day, whereas Ent. faecalis was not cultivable after the 5th and 13th day when stored inside the bottles. The investigation of the bottles that were stored open for a certain amount of time with CO2 bubbling out showed only single colonies for S. aureus after the 5th day and no CFUs for Ent. faecalis after the 17th day. A reduction in the two investigated bacterial strains during storage in carbonated mineral water bottles means that a proper standardized disinfection and cleaning procedure, according to valid hygiene standards of industrial bottling machines, cannot be replaced by carbonation.

High-Speed Dental Instruments: An Investigation of Protein-Contaminated Dental Handpieces with the Bicinchoninic Acid Assay in Dental Offices in Styria, Austria

Due to permanent contact with bodily secretions such as blood and saliva, the dental workplace poses a high risk of infection for patients as well as for personnel. High-speed dental instruments are still considered one of the major hygienic risks, as the high-speed rotation of the attachments leads to the retraction of infectious material from patients' oral cavities. The aim of this study was to investigate the extent to which dental handpieces are contaminated after use. Spray-water samples were taken from different handpieces used in seven dental offices and protein concentrations were measured photometrically. In the first part of the study, samples were collected from each handpiece before and after the treatment of the patients. Additionally, the changes in protein concentration after consecutive treatments in which the same high-speed dental instrument was used were investigated. The results demonstrated measurable protein concentrations in 91.2% of a total of 398 samples, and 96.4% of the spray-water samples taken after treatment showed a discrepancy from the initial measured protein concentration. In 68.4% an increase in protein concentration was observed, whereas in 27.9% a decrease was measured. In conclusion, the internal contamination of high-speed dental instruments frequently occurs in daily usage and consequently may lead to the transmission of infectious agents by flushing the contaminated water out of the spray water tubes. Moreover, it must be pointed out that internal cleansing of handpieces is insufficient and that a final mechanical disinfection is indispensable.

Corrigendum: Variation in accessory genes within the Klebsiella oxytoca species complex delineates monophyletic members and simplifies coherent genotyping

[This corrects the article DOI: 10.3389/fmicb.2021.692453.].

Concentrations of mesophilic bacteria in a poultry farm over two fattening periods focusing on the presence of staphylococci and enterococci

The increasing animal numbers have a potential impact on the air quality of stables. The aim of this study was to assess the microbial load in the barn air from the day of entry of the chickens to the day of removal for slaughter. Ten measurements in two fattening periods were conducted in a poultry farm with a capacity of 400 chickens in Styria, Austria. The samples were collected with an Air-Sampling Impinger for the investigation of mesophilic bacteria, staphylococci and enterococci. Chicken skin swab samples were collected to detect Staphylococcus aureus. The total colony forming units per cubic meter of mesophilic bacteria of the first measurement series of period I was 7.8×104 and increased to 1.4×108 at the end and at the fattening period II it increased from 2.5×105 to 4.2×107. In the measurement series of the fattening period I, the concentration of Staphylococcus spp. increased from 0 to 4.9×107 CFUs/m3 and from 0 to 2.1×107 CFUs/m3 in the fattening period II.

Staphylococcus aureus could not be found in the chicken skin. An interesting finding was the increase of staphylococci while the intestinal enterococci were not detectable in the air of the barn towards the end of both fattening periods.

Multiresistant Bacteria Isolated from Intestinal Faeces of Farm Animals in Austria

In recent years, antibiotic-resistant bacteria with an impact on human health, such as extended spectrum β-lactamase (ESBL)-containing Enterobacteriaceae, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE), have become more common in food. This is due to the use of antibiotics in animal husbandry, which leads to the promotion of antibiotic resistance and thus also makes food a source of such resistant bacteria. Most studies dealing with this issue usually focus on the animals or processed food products to examine the antibiotic resistant bacteria. This study investigated the intestine as another main habitat besides the skin for multiresistant bacteria. For this purpose, faeces samples were taken directly from the intestines of swine (n = 71) and broiler (n = 100) during the slaughter process and analysed. All samples were from animals fed in Austria and slaughtered in Austrian slaughterhouses for food production. The samples were examined for the presence of ESBL-producing Enterobacteriaceae, MRSA, MRCoNS and VRE. The resistance genes of the isolated bacteria were detected and sequenced by PCR. Phenotypic ESBL-producing Escherichia coli could be isolated in 10% of broiler casings (10 out of 100) and 43.6% of swine casings (31 out of 71). In line with previous studies, the results of this study showed that CTX-M-1 was the dominant ESBL produced by E. coli from swine (n = 25, 83.3%) and SHV-12 from broilers (n = 13, 81.3%). Overall, the frequency of positive samples with multidrug-resistant bacteria was lower than in most comparable studies focusing on meat products.

Variation in Accessory Genes Within the Klebsiella oxytoca Species Complex Delineates Monophyletic Members and Simplifies Coherent Genotyping

Members of the Klebsiella oxytoca species complex (KoSC) are emerging human pathogens causing infections of increasing significance especially in healthcare settings. KoSC strains are affiliated with distinct phylogroups based on genetic variation at the beta-lactamase gene (bla _OXY) and it has been proposed that each major phylogroup represents a unique species. However, since the typing methods applied in clinical settings cannot differentiate every species within the complex, existing clinical, epidemiological and DNA sequence data is frequently misclassified. Here we systematically examined the phylogenetic relationship of KoSC strains to evaluate robustness of existing typing methods and to provide a simple typing strategy for KoSC members that cannot be differentiated biochemically. Initial analysis of a collection of K. oxytoca, K. michiganensis, K. pasteurii, and K. grimontii strains of environmental origin showed robust correlation of core phylogeny and blaOXY grouping. Moreover, we identified species-specific accessory gene loci for these strains. Extension of species correlation using database entries initially failed. However, assessment of average nucleotide identities (ANI) and phylogenetic validations showed that nearly one third of isolates in public databases have been misidentified. Reclassification resulted in a robust reference strain set for reliable species identification of new isolates or for retyping of strains previously analyzed by multi-locus sequence typing (MLST). Finally, we show convergence of ANI, core gene phylogeny, and accessory gene content for available KoSC genomes. We conclude that also the monophyletic members K. oxytoca, K. michiganensis, K. pasteurii and K. grimontii can be simply differentiated by a PCR strategy targeting bla _OXY and accessory genes defined here.

Background Concentrations of Cultivable, Mesophilic Bacteria and Dust Particles in the Air in Urban, Rural and Mountain Regions

Particulate air components can be of anthropogenic or natural origin. It is assumed that in different geographical areas varying concentrations of mesophilic bacteria are present in the ambient air. The aim of this study was to determine the background concentrations of airborne culturable mesophilic bacteria and particulate matter in the ambient air. Furthermore, the association between their concentrations and some environmental factors was analysed. In the period from July to October 2019, concentrations of mesophilic bacteria and dust particles were measured in urban, rural and mountain areas using the single-stage air sampler and the particle counter. The concentrations of bacteria and dust particles in the air were counted as number of Colony Forming Units per cubic metre (CFU/m³) and particles per cubic metre (pa/m³). Staphylococcus sp. were identified. The median values of the cultivated mesophilic bacteria at 30 °C and 37 °C were 7.1 × 10² CFU/m³ and 2.3 × 10¹ CFU/m³ in mountain regions, 1.3 × 10² CFU/m³ and 6.9 × 10¹ CFU/m³ in rural regions and 2.1 × 10² CFU/m³ and 6.5 × 10¹ CFU/m³ in urban regions. The median of Staphylococcus sp. was 2.5 × 10⁰ CFU/m³ in alpine areas and 7.5 × 10⁰ CFU/m³ in urban and rural areas. Higher bacterial concentrations were measured in sunshine and in windy weather. A relationship was observed between the concentrations of airborne mesophilic bacteria and the coarse particles in all three areas. The present study determined values between 5.0 × 10⁰ and 4.6 × 10² CFU/m³ as natural background concentrations of airborne mesophilic bacteria and 1.2 × 10⁷ pa/m³ and 6.5 × 10⁴ pa/m³ for fine and coarse particles, respectively. These results can be proposed as baseline for the assessment of the emission sources of mesophilic bacteria for summer and early autumn.

Correction: Comparative study of impaction and sedimentation in an aerosol chamber using defined fungal spore and bacterial concentrations

[This corrects the article DOI: 10.1371/journal.pone.0187039.].

Prevalence, antibiotic resistance patterns and molecular characterization of Escherichia coli from Austrian sandpits

The aim was to determine the prevalence of E. coli and coliform bacteria in playground sand of all public children's sandpits in Graz (n = 45), Austria, and to assess the frequency of antimicrobial resistance in E. coli. Molecular characterization included the discrimination of O-serotypes and H-antigens and the determination of virulence and resistance genes, using a microarray technology. E. coli isolates were tested for susceptibility to a set of antibiotics by VITEK2 system and disk diffusion method. In total, 22 (49%) and 44 (98%) sandpits were positive for E. coli and coliform bacteria. Median concentrations of E. coli and coliform bacteria in the sand samples were: 2.6 × 10(4) CFU/100 g and 3.0 × 10(5) CFU/100 g. Resistance rates were: ampicillin, 12.5%; piperacillin, 10.4%; amoxicillin/clavulanic acid, 9.4%; cotrimoxazole, 6.3%; tetracycline, 6.3%; piperacillin/tazobactam, 5.2%. No ESBL- or carbapenemase-producing isolates were found. The most prevalent serogroups were O15, O6 and O4. Isolates harbored 0 up to 16 different virulence genes.

Water quality assessment of a Central European River - does the Directive 2000/60/EC cover all the needs for a comprehensive classification?

Over the last decades, European rivers have mostly shared the same fate. Until the mid 1980s many of them were in rather bad shape. Nobody would have thought about using the waters for recreation. However, continuous efforts over the last three decades have achieved success and today's water quality has changed to the better. This obvious change in water quality, which was proved by investigations done on the basis of the European Directive 2000/60/EC framework for Community action in the field of water policy, made people consider using the rivers for recreation or irrigation. In the present study a Central European River was investigated from hygienic perspectives (faecal indicators), and its toxicological status was examined - both of which are parameters which are not included in the Directive 2000/60/EC. The pivotal question was whether these parameters provide essential and additional information about the river's status and its quality. In general, the monthly values for all sampling points from the toxicological tests correlated with the determined physical and chemical statuses according to the national water management plan. Once, however, the toxicological values did increase significantly. This detection of a single toxicological burst within a year of observation underlines the applicability of the tests as screening methods for the detection of toxic substances. Moreover, our microbiological investigations show high numbers of faecal indicators and Salmonellae. These results are not consistent with the apparently good quality of the river. Therefore faecal indicators, which are directly related to the discharge of waste water, should be an integral part of the procedure of water classification.

Transmission ofCampylobacterspp. in a poultry slaughterhouse and genetic characterisation of the isolates by pulsed-field gel electrophoresis

1. Contamination of retail products with Campylobacter spp. during the slaughter of poultry is a well-known problem of product hygiene. Mechanical evisceration often leads to intestinal rupture and discharge of gut contents, which can contain zoonotic and human pathogens. Processes along the slaughter line cause aerosols and airborne droplets, containing bacterial loads. 2. To estimate the possible transmission routes of intestinal Campylobacter, 36 measurements of the bioaerosol (Andersen sampler and SKC BioSampler), 30 cloacal (of three flocks), 10 equipment and 4 sedimentation samples were tested for the presence of Campylobacter species. 3. The results imply that, in addition to contaminated equipment, which was Campylobacter-positive in 80% of cases, aerosols with peak values of 4.0 x 10(4) (test series 1) and 1.4 x 10(4) (test series 2) CFU/m3 also provide a potential vector for horizontal transmission. 4. To explore the genetic similarities of isolates from different origins, 18 isolates recovered from air, 26 cloacal, 8 equipment and 4 sedimentation isolates were analysed by pulsed-field gel electrophoresis (PFGE), using the restriction enzymes Sma I and Sal I. The similarity of cloacal isolates with isolates from equipment, air and sediment, suggest that the contamination is of intestinal origin. 5. There were direct links between Campylobacter-positive flocks and the presence of the same strains in the aerosol of the slaughter hall. Air as a potential source for microbial transmission must be taken into account.

Lethal brain abscess due to the fungusScedosporium apiospermum(teleomorphPseudallescheria boydii) after a near-drowning incident: case report and review of the literature

A 39-year-old healthy man developed a brain abscess weeks after a near-drowning incident. Scedosporium apiospermum, the anamorph of Pseudallescheria boydii, was isolated from the abscess. The patient died 153 days after the accident despite antifungal therapy. We discuss the role of antifungals and review the literature for comparable cases.

Antibiotic resistance of E. coli in sewage and sludge

The aim of the study is the evaluation of resistance patterns of E. coli in wastewater treatment plants without an evaluation of basic antibiotic resistance mechanisms. Investigations have been done in sewage, sludge and receiving waters from three different sewage treatment plants in southern Austria. A total of 767 E. coli isolates were tested regarding their resistance to 24 different antibiotics. The highest resistance rates were found in E. coli strains of a sewage treatment plant which treats not only municipal sewage but also sewage from a hospital. Among the antimicrobial agents tested, the highest resistance rates in the penicillin group were found for Ampicillin (AM) (up to 18%) and Piperacillin (PIP) (up to 12%); in the cephalosporin group for Cefalothin (CF) (up to 35%) and Cefuroxime-Axetil (CXMAX) (up to 11%); in the group of quinolones for Nalidixic acid (NA) (up to 15%); and for Trimethoprime/Sulfamethoxazole (SXT) (up to 13%) and for Tetracycline (TE) (57%). Median values for E. coli in the inflow (crude sewage) of the plants were between 2.0 x 10(4) and 6.1 x 10(4)CFU/ml (Coli ID-agar, BioMerieux 42017) but showed a 200-fold reduction in all three plants in the effluent. Nevertheless, more than 10(2)CFU E. coli/ml reached the receiving water and thus sewage treatment processes contribute to the dissemination of resistant bacteria in the environment.

In-vitro response of Plasmodium falciparum to the main alkaloids of Cinchona in northwestern Thailand

The blood schizontocidal activity of the four main Cinchona alkaloids against Plasmodium falciparum was compared in 46 fresh parasite isolates, using an in-vitro test measuring the drug-specific inhibition of schizont maturation. The studies were conducted in June-August 2001 at Mae Sot, northwestern Thailand, an area where quinine alone is no longer able to eliminate infections with P. falciparum. Quinidine showed the highest blood schizontocidal activity, followed by cinchonine, cinchonidine and finally quinine, which was identified as the least active compound. The isolates showed marked heterogeneity in their response to the Cinchona alkaloids. There was also high correlation of activity among all four alkaloids. The mean EC50 values for quinine, quinidine, cinchonine and cinchonidine were 144 nM, 80 nM, 104 nM and 225 nM, respectively, and the EC99 values 8040 nM, 861 nM, 1176 nM and 6531 nM. The EC99 values for quinine and cinchonidine are beyond the therapeutic concentration range and those for quinidine within it. For cinchonine, values are likely to be within this range, but toxicological and pharmacokinetic studies on this compound are required for clarifying its potential future role in the treatment of falciparum malaria.

Comparative investigation of airborne culturable microorganisms in sewage treatment plants

The present study investigated emissions and emmissions of airborne microorganisms (mesophilic bacteria, Escherichia coli, molds, Aspergillus fumigatus, thermophilic actinomycetes/bacilli) in sewage treatment plants. For the aerobiological investigations three sewage treatment facilities with an activated-sludge process, capacities between 2000 and 28,000 PE and different cleaning steps were selected. The measurements of microorganism emission were conducted in the area of the intake (screen), in the area of biological treatment (activated sludge tank) and at a distance of 10 m from the activated sludge tanks. In order to determine the emmission, additional measurements were conducted leeward of the plant at a distance of 200 m. Samples were taken using four parallel six-stage Andersen 1 AFCM volumetric samplers. In the area of the intake counts for bacteria were 7.4 x 10(2) CFU/m3 (median), for thermophilic actinomycetes 1.8 x 10(1) CFU/m3, for thermophilic bacilli 7.1 x 10(1) CFU/m3, for molds 2.4 x 10(3) CFU/m3 and for Aspergillus fumigatus 1.8 x 10(1) CFU/m3. Only isolated airborne coliform recoveries, i.e. E. coli, were detected. In the area of the activated sludge tank, in the adjoining area (10 m) and in the vicinity of the plants (200 m), the counts for all microorganism groups investigated corresponded to natural conditions. The results show that the counts of culturable aerogenic microorganisms in and in the immediate surrounding of the sewage plants investigated are low. Although the possibility of an infection through inhalation cannot be ruled out, the direct contact with sewage is much more critical.

[Waste management--health: a longitudinal study]

Altogether 256 (148 men and 108 women) employees from manual sorting facilities and 120 (98 men and 22 women) employees from compost facilities were examined The main focus of the investigations was in the assessment of the lung-function and the immune-system. A part of employees (87 in sorting and 34 in compost facilities) was observed over a period of 3 years. The lung-function was in the area of the expected values, decreased however from year to year. The concentration of total-IgE increased over the period of 3 years. The observation is from great interest that the difference of the concentration of the total-IgE fluctuated within the 3 years at the employees of manual sorting facilities from +200% to -100% while it amounted to 0% at employees of the compost facilities.

[Comparative studies of airborne, cultivatable microorganisms at selected sites of waste managements, domestic animal husbandry and in the surrounding residential area]

During the last years, sampling of airborne microorganisms (including mesophilic bacteria, moulds, thermophilic bacteria and A. fumigatus) in waste disposal, recycling industry and control sampling locations in the urban and rural districts of Graz was conducted using Andersen 6-stage viable cascade impactors. In the present study additional sampling in livestock buildings has been conducted. Except mesophilic bacteria the emission in the area of waste disposal and recycling industry was significantly higher than in livestock buildings. In the surroundings of the livestock buildings the number of microorganisms was not increased, while the normal background level in the surroundings of the waste proceeding plants was reached from a distance of 150 to 300 meters.

Comparative investigations of airborne culturable microorganisms in selected waste treatment facilities and in neighbouring residential areas

The evaluation of airborne microorganisms in waste treatment facilities is complicated by different measuring systems, a lack of measuring standards and large variations between individual counts. In the present study, different sectors of the waste management industry were compared by determining median values of airborne culturable microorganisms from numerous parallel counts over a prolonged time period. The samples were taken during the warm season using the six-stage Andersen volumetric sampler in a large composting plant and its immediate vicinity, in an agricultural composting plant, a waste disposal site, and a sorting facility for recyclable materials. Control samples were taken at a site not influenced by the waste management industry in an open and largely uninhabited area. The highest median values for culturable bacteria (37 degrees C) found were 1.1 x 10(5) CFU/m3, for moulds (25 degrees C) 1.4 x 10(5) CFU/m3, and for A. fumigatus (37 degrees C) 1.7 x 10(4) CFU/m3 in the sorting cabins of the sorting facility (p < 0.001). The highest median values for thermophilic bacteria (actinomycetes and bacillaceae, 50 degrees C) were 7.3 x 10(3) CFU/m3 in the large composting facility. In all other facilities as well as in the neighbouring residential areas of all facilities investigated, all median values were significantly lower and corresponded to the naturally occurring levels: approx. 10(2) CFU/m3 for bacteria, approx. 10(3) CFU/m3 for moulds and approx. 10(1) CFU/m3 for A. fumigatus and thermophilic bacteria. Only in the neighbouring residential area of the large composting plant, the median values for thermophilic bacteria were approx. 10(2) CFU/m3, but an additional impact from farms cannot be excluded in this case. These results show permanent increased loads of the investigated microorganisms inside large composting facilities and especially in the sorting cabins for recyclable materials. The increasing number of reports on potential health hazards in these areas require adequate measures on the part of occupational medicine in order to limit the health risk to a minimum. The most important task is the automatization of the sorting process for recyclable materials.

Diarrhea in returning Austrian tourists: epidemiology, etiology, and cost-analyses

BACKGROUND

Between 1995 and 1997, stool samples of 322 Austrian tourists returning from abroad with diarrhea were examined for bacteria, parasites and viruses.

METHODS

Epidemiologic data were collected from information furnished by physicians and hospitals and from questionnaires. Moreover, testing expenses and additional cost for treated cases were evaluated.

RESULTS

In 97 of 322 patients examined (30%), one or more pathogens were detected in the stool. Bacteria were found in 38 patients (39%), parasites in 33 patients (34%) and viruses in 26 patients (27%). In 6 patients, mixed infections with parasites and viruses were detected and in 5 patients with bacteria and viruses. Among bacteria, Campylobacter jejuni was most frequent; among parasitic infections, Giardia lamblia. Significant correlations were established between the country of destination, age, travel style and length of stay. Forty-four percent of all patients visited Asia (including Turkey), 27% Africa, 18% Latin America, and only 10% southern Europe. The group between 20 and 29 years of age was most frequently affected (p<.001), the group between 0 and 19 years of age least. Fifty-seven percent stayed in a hotel without frequent changes of location; 43% undertook a trekking trip; and of those, 75% belonged to the group aged between 20 and 39. In terms of the correlation between travel style and pathogen, it was found that 74% of patients with bacterial infections stayed in a hotel (avg. 57.9%; p<.05) whereas 64% of all patients with parasitic infections undertook a trekking trip (avg. 42%; p<.001). Thirty-six percent of all patients with parasitic infections spent their vacation in India (avg. 13%; p<.001). The length of stay of patients with bacterial infections was shorter than average (72% spent between 1 and 2 weeks abroad, avg. 49.8%). Patients with parasitic infections spent significantly more time abroad than average (42% more than 2 months; avg. 17.7%; p<.001). Average cost of specific antimicrobial therapy was U.S.$31 whereas the average cost of identifying a patient needing such treatment was almost U.S.$580.

CONCLUSION

Optimal detection rate and cost reduction for the diagnosis require precise history, adequate collection of samples using adequate transport media, and rapid transfer to the laboratory.

Air-borne microorganisms in the metropolitan area of Graz, Austria

Urban and rural regions are affected by different microorganism loads depending on their structure and utilization. At 7 sampling sites in the metropolitan area of Graz, counts of airborne bacteria as well as yeasts and molds were conducted over a one-year period at two-week intervals. Bacteria and yeasts/molds counts in a village area to the South of Graz dominated by agriculture exceeded the corresponding counts in a suburban residential area fourfold (327 CFU/m3 air-bacteria) and twofold (185 CFU/m3 air-yeasts/molds) respectively. In the vicinity of a composting facility located in the same residential area, microorganism counts exceeded those of the neighboring "unaffected" area by 29% in the case of bacteria and by 54% in the case of yeasts/molds. At an industrial and business site with heavy traffic, the counts are twice that of the area affected by the composting facility (146 CFU/m3 for bacteria and 168 CFU/m3 for yeasts/molds). The proportion of Aspergillus fumigatus is highest in the village area with 23%, compared to 10% in the open land. 49% of the bacteria and 54% of the yeasts and molds can be shown on stages 4-6 of the Andersen-Volumetric-Sampler registering the respirable particle sizes.

Rapid detection of Legionella species in bronchoalveolar lavage fluids with the EnviroAmp Legionella PCR amplification and detection kit

A molecular assay based on a rapid DNA extraction protocol and the EnviroAmp Legionella Kits was used to detect Legionella species in bronchoalveolar fluid specimens. All Legionella strains isolated from tap water in hospitals could be detected distinctly. Both sensitivity and specificity were tested. In a prospective study, bronchoalveolar lavage fluids obtained from patients with atypical pneumonia were investigated. Three positive samples were detected with the molecular techniques and were subsequently confirmed by culture. Application of the system described may lead to safe and early diagnosis of Legionnaires' disease in patients with atypical pneumonia.

Comparative study of procedures for isolation and cultivation of Legionella pneumophila from tap water in hospitals

For the isolation and cultivation of Legionella pneumophila from tap water in hospitals, we compared different media and selection techniques. A second part of the study compared the L. pneumophila yields from different water samples at identical sites. A total of 210 water samples (500 ml each) were collected from two selected sites in each of 21 hospitals. Warm water samples were collected after flow times of 0, 5, 10, and 15 min; in addition, one cold water sample was collected. Filtration was used to concentrate all samples. Following filtration, 0.1 and 1 ml each of untreated samples, heat-treated samples (3 min, 59 degrees C), and acid-treated samples (pH 2.2, 15 min) were spread onto the selective media MWY (SR 118; Oxoid) and BMPA alpha (SR 111; Oxoid), and samples from 12 hospitals were also spread onto GVPC medium (SR 152; Oxoid). A total of 72 (34%) of the 210 samples from 12 hospitals were positive. With respect to the positive Legionella cultures, there was no significant difference between the selective media MWY, BMPA alpha, and GVPC. With the BMPA alpha supplement, more samples were positive following heat treatment (P < 0.05) or acid treatment (P < 0.05) than without any further treatment. For the maximum yield of Legionella colonies with minimum additional microbial flora, acid treatment was the most effective, and by all methods, the GVPC supplement was the most selective. For routine water tests in hospitals for differentiating between systemic and local contamination, acid treatment of the concentrated samples, the use of different selective media, and the correct selection of sampling sites are recommended.

[Detection of legionellae in thermal water]

Water samples taken from hot water springs, from the water distribution system and from various places of consumption of thermal water were collected in an Austrian spa. 56.5% of the samples contained Legionella; serogroups 1, 3 and 5 of Legionella pneumophila were most frequently identified. The large number of positive Legionella samples indicates a potential risk of infection to patients, especially those undergoing inhalation treatment with thermal water, or those using a whirlpool or taking a shower. In those inhalators actually in use, no Legionella could be detected. Thus they are no source of infection when they are maintained and serviced properly. Thermal disinfection and service checks at regular intervals are suggested for the contaminated systems.

Hygienic investigation of coastal waters of the upper Adriatic Sea

In the course of the bathing season of 1989, investigations of bathing waters were carried out in two-week intervals. From the point of view of public health, the chemical-physical and microbiological results do not suggest objections against bathing at the beach areas investigated (Grado, Lignano). However, these favorable results do not imply intact ecological conditions. National and international standards are designed for humans and allow only very limited conclusions about the living conditions of the marine ecosystem. This also means that ecological investigations are not sufficient to permit conclusions about hygienic conditions. In spite of this seeming contradiction, hygienic and ecological concerns are clearly identical. Hygienic measures must not be limited to local "cosmetic" corrections but must target foremost unfavorable basic conditions.

Cryptosporidiosis in children in Idukki District in southern India

Concentrated stool samples from 560 children, aged from two weeks to 10 years, from Idukki District, southern India, were examined to detect Cryptosporidium oocysts, using a phenol-auramin stain and fluorescent microscopy. Smears of stool samples were also stained by a modified Ziehl-Neelsen method and were examined by light-microscopy. One sample was collected from each of 266 children with diarrhoea and 294 age-matched children without diarrhoea. Cryptosporidium oocysts were detected in 4.5% of all stools, in 6% of diarrhoeal stools and in 3% of stools from healthy controls. Results of the study show that Cryptosporidium infection is common in children with diarrhoea in southern India, and there is also a high frequency of asymptomatic cyst-passers in this area.

[Blastocystis hominis--intestinal parasite or commensal?]

Blastocystis hominis has long been classified among Blastomycetes. It was considered to be an apathogenous fungal organism which was very frequently detected in routine stool examinations. Following the first studies with an electronic microscope in 1967, Zierdt et al. (34) classified Blastocystis hominis among the protozoa. Since then, there have been increasingly frequent reports that Blastocystis hominis can be an important cause of intestinal diseases especially diarrhea. For a definite taxonomic correlation and for an identification as pathogen, more investigations are greatly necessary.

Aeromonas species in a municipal water supply of a central European city: biotyping of strains and detection of toxins

In the course of a one-year study, 78 out of 239 samples from a Central European municipal water supply were found to contain Aeromonas species. Biotyping and hemolysin titers according to the criteria of Burke et al. (1) showed that almost 50% of the tested strains can be presumed to be enterotoxin-producing. The remaining microbiological parameters met international standards (20).

Serological examinations for antibodies against Legionella species in dental personnel

Serum samples from 107 dentists, dental assistants, and dental technicians were examined with an indirect immunofluorescence test for antibodies to Legionella pneumophila SG1-SG6, L. micdadei, L. bozemanii, L. dumoffii, L. gormanii, L. jordanis, and L. longbeachae SG1 + 2. Thirty-six (34%) employees from dental personnel from 13 practices showed a positive reaction for antibodies to Legionella pneumophila. Only five samples (5%) from a control group (non-medical workers) were positive. Of the 36 positive serum samples, 13 (36%) reacted with Serogroup 6, 12 with SG 1 (33%), 12 with SG 5 (33%), and three with SG 4 (8%), and eight samples were positive for antibodies to other Legionella species. Dentists had the highest prevalence (50%) of L. pneumophila antibodies, followed by assistants (38%) and technicians (20%). These results indicate that dental personnel are at an increased risk of legionella infection.

A survey of gastrointestinal parasites in Ogun State, southwest Nigeria

To study the epidemiology of intestinal parasites in Ogun State, Nigeria, 479 stool specimens were examined at a hospital in Abeokuta during the rainy season in June 1986. Intestinal helminths and/or protozoa were present in 297 samples (62%). 41.1% of the specimens showed a single infection, 34% showed double, 20% triple and 5% quadruple infection. The most commonly found worm was Ascaris lumbricoides (in 40% of specimens), followed by Trichuris trichiura (23.2%), hookworms (19.2%), Strongyloides stercoralis (2.1%) and Dicrocoelium sp. (0.4%). Pathogenic protozoa found were Entamoeba histolytica (7%), Giardia intestinalis (4.2%), Blastocystis hominis (2.5%) and Cryptosporidum sp. (2.3%). The apathogenic protozoa Entamoeba coli, Chilomastix mesnili, Trichomonas hominis and Iodamoeba buetschlii were also seen.

[Therapeutic possibilities in diseases caused by intestinal parasites]

Compatible and efficient drugs for the therapy, caused by protozoal- or helminthic-infections, are available today. Many of them are not registered in Austria. Metronidazole, Mebendazole and Praziquantel are particularly effective. Most protozoal-infections can be treated with metronidazole. Mebendazole can be used against numerous nematode-infections (Ascariasis, Trichuriasis, Oxyuriasis, Ancylostomiasis), Niclosamide against cestode-infections (Taeniasis, Hymenolepiasis, Diphyllobothriasis), whereas, Praziquantel is applied against trematode-infections.

Cryptosporidiosis in Ogun State, south-west Nigeria

During the period of one month in the rainy season in Ogun State in south-west Nigeria 479 stool samples (420 of which were diarrhoea stool samples) were examined for cryptosporidiosis. Oocysts were detected in 2.3% of all stools, in 2.6% of diarrhoeal stools and in 5.3% out of 150 children with diarrhoea. Cryptosporidium was the sole pathogen detected in six of 11 cases. In addition to cryptosporidia also Entamoeba histolytica, Blastocystis hominis, Giardia lamblia, Ascaris lumbricoides, and Trichuris trichiura could be found. Compared to other studies in tropical countries, the frequency of infection was lower in south-west Nigeria.