High level of recovery of fungi from water and dialysate in haemodialysis units

The counts of yeasts and filamentous fungi were investigated in the municipal water supplies of haemodialysis centres, in the treated water and the dialysate from all 85 haemodialysis units in Greece, in order to estimate their occurrence, their correlation with contamination indicator bacteria and other influencing factors. Filamentous fungi and yeasts were isolated from 69 (81.2%) and from three (3.5%) feed water samples, from 74 (87.1%) and seven (8.2%) treated water samples and from 66 (77.7%) and 11 (12.9%) dialysate samples respectively. Aspergillus spp and Penicillium spp were the most frequent moulds, while Candida spp were the prevailing yeasts. The occurrence of yeasts was significantly higher in dialysate than in tap water samples. Counts of filamentous fungi in all 255 samples were significantly correlated with the counts of total heterotrophic bacteria and enterococci, whereas the counts of yeasts were correlated with faecal coliforms, total heterotrophic bacteria, as well as enterococci, Pseudomonas spp and total coliforms, while no correlation was detected with the age of either haemodialysis units, the age of water treatment system, the number of artificial kidney machines or the components of the water purification system. High recovery of fungi from haemodialysis aqueous environments implies a potential risk for haemodialysis patients and indicates the need for continuous maintenance and monitoring.     

Preliminary surveys about the use of "Mytilus galloprovincialis" as an accumulation matrix of bacteria in coastal waters

A biomonitoring study using "Mytilus galloprovincialis" mussels was carried out, to estimate their possible employment as "natural indicators" of coastal bacterial pollution. The research was conducted from September 2001 to May 2002, twice in a month, near two coastal zones of Salento. We analysed both natural and cultivated mussels. The latter were placed in cages, after checking their starting level of microbiological pollution. The bacteriological analyses conducted simultaneously on mussels and their ambient water, were directed to the search of: total and faecal coliforms, faecal streptococci, Escherichia coli, Salmonella spp., Staphylococcus aureus and yeasts. In this preliminary study the mussels proved to be "sensitive indicators of faecal pollution", since they had an accumulation of the faecal indicators even if the water was not contaminated. Nevertheless a lower frequency in finding yeasts in the mussels (53.8%) in comparison with water (74.3%), the irregular presence of Salmonella spp. in water (3.75%) and its absence in bivalves, show the need of further studies, also through "in vitro" tests, in order to verify absorption/elimination kinetics of microorganisms.     

Diversity and antifungal susceptibility of yeasts isolated by multiple-tube fermentation from three freshwater lakes in Brazil

The diversity and antifungal resistance of yeasts able to grow at 37°C and the occurrence of bacterial indicators of water quality were studied in three lakes in Southeastern Brazil. The densities of yeasts, Escherichia coli, Enterococcus spp. and Pseudomonas aeruginosa were determined by the multiple-tube fermentation technique, and counts of heterotrophic bacteria were determined using the pour plate method. The yeasts were identified using physiological and molecular techniques and their resistance to amphotericin B, itraconazole and fluconazole was tested. Yeast occurrence was significantly correlated only with the density of fecal coliforms. Candida krusei, C. guilliermondii and C. tropicalis, the most frequently isolated yeast species, are associated with fecal contamination of water by warm-blooded animals. Yeast isolates were most resistant to amphotericin B (21.7%), followed by itraconazole (20%) and then fluconazole (2.8%). In addition to tests for the fecal coliform group, the density of yeasts grown at 37°C could be used as a complementary microbial indicator that aquatic environments contain organic matter of human origin. The incidence of yeast species resistant to three antifungal drugs shows that these microorganisms could pose a health risk to the people who use these lakes for recreation.     

Faecal contamination indicators, Salmonella, Vibrio and Aeromonas in water used for the irrigation of agricultural products

The faecal contamination indicators (total coliforms, faecal coliforms, Escherichia coli, enterococci) and the genera Salmonella, Vibrio, Aeromonas were investigated in water samples used for irrigation. During 4 months, 52 samples were taken. The methods used were: multiple tube fermentation method for faecal contamination indicators and membrane filtration techniques for salmonella, aeromonas and vibrio. Two samples were positive for Salmonella spp., fourteen for Aeromonas spp. and no samples for Vibrio spp. No correlation was found between aeromonas and the indicators of faecal contamination. Regarding Aeromonas spp., 21.6% of the strains were adhesive and 12.6% cytotoxic: this confirms the possible role of aeromonas in human pathologies. These results are important to determine the quality of irrigation water in relation to human health. In fact, the spray or sprinkler irrigation produces bioaerosol, which can contaminate the crops that are likely to be eaten uncooked. In addition, the flood or furrow irrigation represents a risk to field workers.     

Bacteriological quality of groundwaters in cemeteries]

Groundwater samples collected by piezometers from three cemeteries in geologically distinct areas of S. Paulo and Santos, Brazil, were analysed in order to determine their hygienic and sanitary conditions. Fecal coliformes, fecal streptococci, sulfite reducer clostridia and Salmonella were searched for the purpose of evaluating sanitary conditions, and total coliforms, heterotrophic bacteria, proteolitic and lipolitic microorganisms for evaluating hygienic conditions. In some samples, nitrate levels were also determined. It was discovered that these waters do not present adequate sanitary and hygienic conditions and that, in some cases, nitrate levels were extremely high (75.7 mg/l). In most samples, higher levels of fecal streptococci and sufite reducer clostridia than fecal coliforms were detected, which seems to show that the two former indicators would be more appropriate for evaluating the sanitary conditions of this kind of water. Salmonella were detected in only one of 44 samples analysed and coliphages in none. In the statistical analysis, the correlation matrix showed significant correlations among three fecal pollution indicators, as well as among anaerobic and aerobic heterotrophs and lipolitic bacteria. A direct relationship between the deterioration of water quality and the geological and hydrogeological conditions of the environment studied was observed. When cemeteries are constructed these conditions should, therefore, be taken into consideration.     

Monitoring of airborne fungus and yeast species in a hospital unit

OBJECTIVE: To monitor and characterize airborne filamentous fungi and yeasts from abiotic and biotic sources within a hospital unit. METHODS: Collections were carried out on a monthly basis, at two different time periods, from the adult and pediatric intensive care units and surgical center of a hospital in Araraquara, Southeastern Brazil. Collection of airborne fungi was carried out using a simple-stage Andersen sample. The presence of yeasts was investigated in samples taken from the hands and oropharynx of staff members as well as from the surface of beds and doorknobs inside the critical areas. RESULTS: Thirty-two genera of airborne fungi and were recovered from the surgical center and 31 from the intensive care units. Genera most frequently isolated were Cladophialophora spp., Fusarium spp., Penicillium spp., Chrysosporium spp. e Aspergillus spp. During the study period, a new unit was built in the hospital, which coincided with an increase in Cladophialophora spp., Aspergillus spp., and Fusarium spp. colony counts. Yeasts were found in 39.4% of samples obtained from healthcare staff (16.7% from interdigital spaces, 12.1% from nailbeds, and 10.6% from oropharynx) and in 44% of furniture samples, with a predominance of the Candida genus ((C. albicans, C. guilliermondii, C. parapsilosis e C. lusitaniae), followed by Trichosporon spp. CONCLUSIONS: We found a relatively high number of airborne fungi (potentially pathological) in special areas and expressive levels of yeasts in both biotic and abiotic samples. Microbiological and environmental monitoring should be conducted, especially in special areas which include immunocompromised patients, who are more susceptible to the exposure to environmental and staff-derived pathogens.     

A prospective study of swimming-related illness. II. Morbidity and the microbiological quality of water

A prospective cohort epidemiological-microbiological study was carried out at 10 beaches in Ontario, Canada. Lake water and sediment samples collected at the beaches were analyzed for fecal coliforms, fecal streptococci, heterotrophic bacteria, Pseudomonas aeruginosa, and total staphylococci. Mean fecal coliform levels in the surface water of the lakes were within accepted guidelines. Bacterial densities were found to be approximately 10 times higher in the sediment than in the corresponding surface water samples. Morbidity among swimmers was shown to be related to staphylococcal counts, to fecal coliform levels, and, somewhat less strongly, to fecal streptococcal counts. Total staphylococci appeared to be more consistent indicators for predicting total morbidity rates among swimmers.     

Screening of some food poisoning bacteria in sausage and hamburger meat

Microbial investigation of 30 samples of sausage meat and 30 samples of hamburger meat, freshly prepared, were collected randomly from different markets in Alexandria city, to determine the bacteriological status of these products. The average counts/gm of total bacteria, total coliforms and fecal coliform in sausage meat were 1.33 x 10(7), 9.16 x 10(5) and 1.11 x 10(3) respectively, and in hamburger samples were 8.47 x 10(5), 2.63 x 10(3) and 1.35 x 10(3) respectively. Shigella, Escherichia coli, Staphylococcus aureus and Proteus spp were isolated with various percentages, whereas Salmonella spp was isolated from sausage only. The public health importance of the isolated microorganisms are fully discussed.     

Microbiological beach sand quality in Gaza Strip in comparison to seawater quality

Gaza beach is the only recreational area available for the local inhabitants. It is heavily polluted with treated, partially treated, and untreated sewage from point and nonpoint sources. The majority of the population is below the age of 15 years. This age group is vulnerable to gastrointestinal diseases and usually restricts their activities to beach sand at the swash zone. Five sampling points along the Gaza beach were selected and monitored for 1 year (fortnightly). Microbial sand content was evaluated for fecal coliforms (FC), fecal streptococci (FS), Salmonella, Shigella, and Vibrio. Seawater samples were subjected to similar evaluation. Pseudomonas, yeast, and mold counts were performed for all sand samples as possible sand pollution indicators. Higher fecal indicators (both FC and FS) were obtained in sand than in water in most locations. The frequency of Salmonella and Vibrio isolation was also higher in sand than in water despite the fact that only 10 g of sand were used while 1L of seawater was collected. Statistically significant correlations between FC and streptococci and between Salmonella and Vibrio were found. Similar correlation was also detected between Pseudomonas and Salmonella in sand samples.     

Microbiological evaluation of sugarcane juice sold at street stands and juice handling conditions in São Carlos, São Paulo, Brazil

Fresh sugarcane juice is sold by street vendors without any heat treatment in S?o Carlos, S?o Paulo, Brazil. Twenty-four samples of point-of-sale juice were tested by standard methods to determine heterotrophic bacteria, total and thermo-tolerant coliform counts, Salmonella, and parasites in the juice. 25% of samples showed poor sanitary conditions, with thermo-tolerant coliform levels higher than allowed by Brazilian standards. Salmonella spp. and parasites were absent in all samples. Thermo-tolerant coliforms were detected on the hands of 37% of juice handlers, and heterotrophic bacterial counts reached 2.0 x 10(3) cfu/per hand. Escherichia coli was detected in one hand sample, and no Salmonella spp. was detected. Screening questionnaires were used to interview the vendors, and 62% of interviewees were either unfamiliar with or failed to adopt adequate hygiene for food handling.     

饮水机出水微生物污染状况调查

目的了解饮水机出水物生物污染状况.方法检测33台饮水机饮用前桶内纯净水、饮用3天后、饮用7天后冷、热水出水细菌总数、大肠菌群、致病菌、霉菌和酵母菌.结果饮用前桶内纯净水、饮用3天后冷、热水出水、饮用7天后冷、热水出水的超标率分别为15.2%,45.5%、12.1%、69.7%和21.2%,尤以细菌总数、霉菌和酵母菌超标明显.7天冷水出水超标率明显高于3天冷水出水,P＜0.05.结论饮水机冷水出水微生物污染严重,且随饮用时间延长,超标率不断增高.     

Physicochemical and bacteriological assessment of water quality at the Ross Barnett reservoir in central Mississippi.

The Ross Barnett Reservoir serves as a source of water supply for the city of Jackson, Mississippi, U.S.A. and is an important site for recreational activities for many residents of Mississippi counties. A broad spectrum of illness is associated with water-contact activities like bathing and swimming in recreational waters. In the present research, we assessed the bacteriological quality of water in the Ross Barnett Reservoir and compared the levels of bacteria with the recommended criteria for public health protection. From June 12, 1999 to October 2, 1999, we collected water samples weekly from two different sites in the reservoir and tested them for the following bacteriological parameters: heterotrophic plate counts, total coliforms, fecal coliforms, and fecal streptococci. The samples were also tested for basic physical and chemical characteristics of water. The results of the study indicate that the respective mean concentrations of bacteria (colony forming units per 100 mL of water) in water samples collected from the reservoir were 5.6 x 10(6)+/-1.5 x 10(6) (heterotrophic plate counts), 4.5 x 10(4) +/- 5.3 x 10(4) (total coliforms), 5.0 x 10(2) +/- 1.6 x 10(2) (fecal coliforms), and 9.1x10(1)+/-7.3x10(1) (fecal streptococci). The values of all physical and chemical parameters were at acceptable levels. The bacterial densities, however, often exceeded federal/state guidelines by several orders of magnitude, raising considerable public health concerns. Steps should therefore be taken to develop and implement strategies to improve the water quality and to reduce or eliminate the potential health risks associated with water-contact activities in the Ross Barnett Reservoir.     

Radioactive pollution in freshwater ecosystems from Macedonia, Greece

The levels of radioactive contamination by artificial radiocesium (Cs-137, Cs-134) as well as the concentrations of natural radioisotopes (K-40, Ra-226, Ra-228, Th-228) in sediments and aquatic plants were evaluated in selected aquatic biotopes in Macedonia, Greece. Radionuclide analysis was performed in Marinelli beakers by a gamma spectrometry system with an Hp-Ge detector of 20% relative efficiency. Cs-137 concentration activities are higher in sediment than in plant material; in general, roots showed greater Cs-137 concentration than leaves, while stems showed the lowest concentration. Cs-137 is significantly higher at 95% confidence level in the river Axios than in the rivers Strymon and Aliakmon. Leaves, especially young ones, show K-40 activities higher than roots or stems. From the studied watersystems, the river Axios and Prespa Lake are more contaminated from Cs-137 and Cs-134. K-40 activity is significantly higher at the 95% confidence level in the river Axios than in the rivers Aliakmon and Pinios. The K-40 activity is also high, especially in Prespa Lake. High activities of Ra-226, Ra-228, Th-228, and K-40 were found in Polyphytos Lake, presumably as a result of the operation of the coal power plants in this area.     

Bacteriological quality of some dairy products (kariesh cheese and ice cream) in alexandria

The present study estimated the total viable bacterial density, total and faecal coliforms, and E. coli in Kariesh cheese and ice cream. The study included 160 ice cream and kariesh cheese samples (80 samples each). Ice cream samples were 47 packed (33 cup and 14 stick) and 33 open samples while kariesh cheese samples were 62 open, 18 packed samples (8 of known brand and 10 of unknown brand). Samples were collected from supermarkets, shops and street vendors. All samples were analyzed for enumeration of total viable heterotrophic bacteria using standard pour plate method, and for the determination of the total coliforms, fecal coliforms and E. coli using multiple tube dilution method. Ice cream samples, showed that the total bacterial count was >/=1.5x105 cfu/g in 26 (32.5%) samples, total coliforms were >/= 10 MPN/g in 36 (45.0%) samples, fecal coliforms were detected in 45 (56.3%) samples ,and E. coli was detected in 34 (42.5%). kariesh cheese samples, showed a total coliforms of >/= 10 MPN/g in 54 (67.5%) samples, while fecal coliforms were detected in 64 (80%) samples, and E. coli was detected in 60 (75%). It is recommended to use and implement immediate regulatory measures like good manufacturing practices as well as distribution and retail storage practices for ensuring microbiological safety of ice cream and kariesh cheese.     

Drinking-water quality and issues associated with water vending machines in the city of Los Angeles

The study reported in this paper sampled 40 water vending machines distributed throughout the city of Los Angeles, California, in the water servicing area of the Los Angeles Department of Water and Power. The authors examined water samples for temperature, turbidity, chlorine content, fungal growth, coliform bacteria, fecal coliform bacteria, Pseudomonas spp., Pseudomonas aeruginosa, and heterotrophic plate counts using plate count agar and R2A agar. Roughly 48 percent of the original 40 samples were sampled in a second or third round, and these subsequent samples were examined for coliform bacteria, fecal coliform bacteria, Pseudomonas spp., Pseudomonas aeruginosa, and both heterotrophic plate counts. Observations were made of vending-machine external conditions, identifying information, and permits. Statistically significant associations were found between operator accessibility and poor machine conditions, operator accessibility and permits, and operator accessibility and the servicing interval. Statistically significant associations also were found between operator accessibility and presence of fungi, Pseudomonas spp., and Pseudomonas aeruginosa, and between presence of fungi and the servicing interval. In addition, statistically significant associations indicate that the quality of machine maintenance is a factor in microbial levels. The microbial content of the water suggested a need for further research into potential health effects in susceptible populations.     

Bacteria and disinfection byproducts in water from southern Mexico City

Disinfection byproducts and microorganisms present in drinking water may have deleterious effects on human health. The authors examined bacterial indicators (enterobacteria and Helicobacter pylori [H. pylori]), physicochemical parameters, and trihalomethane (THM) levels to conduct a water quality evaluation in Mexico City, where little is known about disinfection byproducts and microbial counts. Analyses were performed by standard membrane filtration for the enumeration of total coliforms, fecal coliforms, fecal streptococci, and Vibrio species. Other testing consisted of polymerase chain reaction (PCR) for H. pylori, physicochemical parameters by selective electrodes, and THMs by head-space with the use of a gas chromatograph. Indicator bacteria and enterobacteria were detected in 23% of samples, with significant differences between total coliforms, fecal coliforms, and fecal streptococci before and after chlorination. H. pylori was detected in 69% of samples prior to chlorination and 57% postchlorination. THM levels were < 200 microg/l. Chlorine concentrations ranged from < 0.05 mg/l to 35 mg/l. Disinfection at the well does not ensure good water quality for the Mexico City population. The next step will be the monitoring of water quality in the distribution system that supplies dwellings, as well as water obtained directly from the tap.     

湛江市区生活污水有机物和微生物污染调查

目的了解湛江市区酒楼、居民楼和城市污水有机物和微生物污染状况。方法在一年四季中,对4家酒楼、3幢居民住宅楼和4个城市污水排放口污水的水质进行有机物和微生物指标的监测和基本情况调查。结果在酒楼、居民楼和城市污水的监测项目超标率中,粪大肠菌群分别为100%、97.22%、100%,氨氮分别为6.25%、15.28%、22.92%,亚硝酸盐分别为2.08%、1.39%、0。酒楼>100 mg/L耗氧量检出率为1.04%;三类污水的>105个/ml细菌总数检出率分别为96.88%、95.83%、100%。硝酸盐均无超标。肠道致病菌均无检出。城市污水的氨氮超标率明显高于酒楼污水(P<0.01),居民楼污水和酒楼污水的亚硝酸盐超标率差异无显著性(P>0.05)。三类污水的>105个/ml细菌总数检出率、粪大肠菌群超标率两两比较差异均无显著性(P>0.05)。结论市区酒楼、居民楼和城市污水均存在粪大肠菌群的严重污染和氨氮污染,必须加强污水治理。     

Microbial quality of oysters sold in Western Trinidad and potential health risk to consumers

The prevalence and characteristics of Escherichia coli and Salmonella spp. as well as counts of E. coli in raw oysters, condiments/spices, and raw oyster cocktails sampled from 72 vendors across Western Trinidad were determined. The microbial quality of the water used in the preparation of raw oysters was also investigated. Of 200 samples each of raw oysters, condiments/spices and oyster cocktails tested, 154 (77.0%), 89 (44.5%) and 154 (77.0%) respectively yielded E. coli. The differences were statistically significant (P = < 0.001; chi square = 62.91). The mean E. coli count per g in the ready-to-eat oyster cocktail ranged from 1.5 x 10(3) +/- 2.7 x 10(3) in Couva to 8.7x10(6) +/- 4.9x10(7) in San Fernando. One hundred and forty-six (73.0%) oyster cocktails contaminated with E. coli had counts that exceeded the recommended standard of 16 per g. Of a total of 590 E. coli isolates from various sources tested, 24 (4.1%), 20 (3.4%) and 69 (11.7%) were mucoid, haemolytic and non-sorbitol fermenters respectively. Twelve (2.0%) isolates of E. coli were O157 strains, while 92 (46.0%) of 200 E. coli isolates tested belonged to enteropathogenic serogroups. Ninety (45.0%) and 73 (36.5%) of 200 water samples contained total coliforms and faecal coliforms respectively, with counts that exceeded 2.2 coliforms per 100 ml. Salmonella spp. were isolated from 7 (3.5%), 1 (0.5%) and 2 (1.0%) of 200 samples each, of raw oysters, condiments/spices and oyster cocktails respectively. Oysters pose a health risk to consumers in Trinidad, particularly from colibacillosis and salmonellosis, and the need for increased public awareness of this hazard cannot be over-emphasized.     

Bacteriological water assessment of an urban river in Nigeria

The Asa River in Ilorin, Nigeria, which is subject to varied human abuse at its urban fringe areas, was investigated for its pollution status over a period of 2 years. Physical observations including sources of pollution were noted. The degree of faecal pollution was estimated using microbial indicators. Total heterotrophic bacterial counts ranged from 4.5 to 8.5 × 10⁶ ml^‐1 with higher counts occurring during rainy seasons. The total and faecal coliforms ranged from 1.6 X 10⁴ to 1.9 × 10⁷MPN index 100 ml^‐1 were obtained with higher counts being recovered during dry seasons. Between 62 and 92% of the total coliforms were of faecal origin at various locations. It is concluded that for some kilometres the river, especially during the dry season, is simply an offensive and unhealthy drain. The Asa River and its catchment were therefore identified as a high risk environment for humans.     

Human and animal microbial source tracking in a tropical river with multiple land use activities

The enhancement and restoration of the water quality of deteriorating surface water resources can be challenging, particularly for rivers with multiple usages, such as agriculture, animal husbandry, human residence, and industries. Recently, the performance of DNA-based microbial source tracking (MST) indicators detected by end-point and quantitative PCR assays for identifying sources of fecal pollution from human sewage, swine, and cattle and non-host-specific (universal) fecal pollution in the Tha Chin River basin, Thailand, was evaluated. The present study monitored these validated MST markers and various physicochemical and microbial water quality parameters in samples collected from twelve stations along the Tha Chin River during four sampling events in the wet and dry seasons. No significant difference in precipitation was observed between the wet and dry samplings. Universal markers (both PCR and qPCR) were detected in all 48 samples, indicating persistent and continuing fecal contamination. The sewage- and swine-specific qPCR marker concentrations did not vary among the sampling events, whereas cattle-specific qPCR markers were detected only in the wet season. Animal-specific markers were detected in the lower Tha Chin River section, which is characterized by intensive animal farming. Sewage-specific markers were also found in the lower section and near an upstream residential area. The high agreement (87.5–100%) between the PCR and qPCR results suggested that PCR could serve as a lower-cost MST screening test that requires less technical expertise. A multivariate analysis conducted using the survival analysis procedure to include censored data also emphasized the high pollution in the lower section of the river at all sampling events. Universal and swine-specific markers showed moderate correlations with microbial indicators, including total coliforms, fecal coliforms, E. coli, and enterococci. None of the MST markers or microbial parameters were associated with the measured physicochemical parameters. This study provides the first evaluation of MST markers for monitoring surface freshwater in Thailand, and the findings might aid the pollution surveillance of impaired water bodies and the development of strategies for improving their water quality.