scholarly journals Thermotolerant Coliforms Are Not a Good Surrogate for Campylobacter spp. in Environmental Water

2009 ◽  
Vol 75 (21) ◽  
pp. 6736-6744 ◽  
Author(s):  
Karen St-Pierre ◽  
Simon Lévesque ◽  
Eric Frost ◽  
Nathalie Carrier ◽  
Robert D. Arbeit ◽  
...  
Keyword(s):  
Environmental Water ◽  
Indicator Organisms ◽  
Fecal Indicator ◽  
E Coli ◽  
Microbial Monitoring ◽  
Environmental Surface ◽  
Thermotolerant Coliforms ◽  
Eastern Townships ◽  
Campylobacter Spp

ABSTRACT This study aimed to assess the importance of quantitatively detecting Campylobacter spp. in environmental surface water. The prevalence and the quantity of Campylobacter spp., thermotolerant coliforms, and Escherichia coli in 2,471 samples collected weekly, over a 2-year period, from 13 rivers and 12 streams in the Eastern Townships, Québec, Canada, were determined. Overall, 1,071 (43%), 1,481 (60%), and 1,463 (59%) samples were positive for Campylobacter spp., thermotolerant coliforms, and E. coli, respectively. There were weak correlations between the weekly distributions of Campylobacter spp. and thermotolerant coliforms (Spearman's ρ coefficient = 0.27; P = 0.008) and between the quantitative levels of the two classes of organisms (Kendall tau-b correlation coefficient = 0.233; P < 0.0001). Well water samples from the Eastern Townships were also tested. Five (10%) of 53 samples from private surface wells were positive for Campylobacter jejuni, of which only 2 were positive for thermotolerant coliforms. These findings suggest that microbial monitoring of raw water by using only fecal indicator organisms is not sufficient for assessing the occurrence or the load of thermophilic Campylobacter spp. Insights into the role of environmental water as sources for sporadic Campylobacter infection will require genus-specific monitoring techniques.

scholarly journals Salmonella enterica Serovar Typhimurium and Escherichia coli Survival in Estuarine Bank Sediments

2018 ◽  
Vol 15 (11) ◽  
pp. 2597 ◽  
Author(s):  
Mahbubul Siddiqee ◽  
Rebekah Henry ◽  
Rebecca Coulthard ◽  
Christelle Schang ◽  
Richard Williamson ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Growth Patterns ◽  
Estuarine Sediments ◽  
Human Pathogens ◽  
Indicator Organisms ◽  
Fecal Indicator ◽  
E Coli ◽  
Serovar Typhimurium

Estuarine bank sediments have the potential to support the survival and growth of fecal indicator organisms, including Escherichia coli. However, survival of fecal pathogens in estuarine sediments is not well researched and therefore remains a significant knowledge gap regarding public health risks in estuaries. In this study, simultaneous survival of Escherichia coli and a fecal pathogen, Salmonella enterica serovar Typhimurium, was studied for 21 days in estuarine bank sediment microcosms. Observed growth patterns for both organisms were comparable under four simulated scenarios; for continuous-desiccation, extended-desiccation, periodic-inundation, and continuous-inundation systems, logarithmic decay coefficients were 1.54/day, 1.51/day, 0.14/day, and 0.20/day, respectively, for E. coli, and 1.72/day, 1.64/day, 0.21/day, and 0.24/day for S. Typhimurium. Re-wetting of continuous-desiccated systems resulted in potential re-growth, suggesting survival under moisture-limited conditions. Key findings from this study include: (i) Bank sediments can potentially support human pathogens (S. Typhimurium), (ii) inundation levels influence the survival of fecal bacteria in estuarine bank sediments, and (iii) comparable survival rates of S. Typhimurium and E. coli implies the latter could be a reliable fecal indicator in urban estuaries. The results from this study will help select suitable monitoring and management strategies for safer recreational activities in urban estuaries.

scholarly journals Microbial water quality at contrasting recreational areas in a mixed-use watershed in eastern Canada

2021 ◽  
Author(s):  
Ainslie J. Butler ◽  
Katarina Pintar ◽  
Janis L. Thomas ◽  
Manon Fleury ◽  
Stefanie Kadykalo ◽  
...  
Keyword(s):  
Human Health ◽  
Health Risks ◽  
Human Health Risk ◽  
Indicator Organisms ◽  
Eastern Canada ◽  
Recreational Waters ◽  
Fecal Indicator ◽  
E Coli ◽  
Main River ◽  
Pathogen Testing

Abstract Recreational water use is an important source of human enteric illness. Enhanced (episodic) surveillance of natural recreational waters as a supplement to beach monitoring can enrich our understanding of human health risks. From 2011 to 2013, water sampling was undertaken at recreational sites on a watershed in eastern Canada. This study compared the prevalence and associations of human enteric pathogens and fecal indicator organisms. Beach water samples had lower pathogen presence than those along the main river, due to different pollution sources and the hydrological disposition. Pathogen profiles identified from the beach sites suggested a more narrow range of sources, including birds, indicating that wild bird management could help reduce public health risks at these sites. The presence and concentration of indicator organisms did not differ significantly between beaches and the river. However, higher concentrations of generic Escherichia coli were observed when Salmonella and Cryptosporidium were present at beach sites, when Salmonella was present at the river recreational site, and when verotoxigenic E. coli were present among all sites sampled. In this watershed, generic E. coli concentrations were good indicators of potential contamination, pathogen load, and elevated human health risk, supporting their use for routine monitoring where enhanced pathogen testing is not possible.

Determination of Norovirus Contamination in Oysters from Two Commercial Harvesting Areas over an Extended Period, Using Semiquantitative Real-Time Reverse Transcription PCR

2008 ◽  
Vol 71 (7) ◽  
pp. 1427-1433 ◽  
Author(s):  
JAMES A. LOWTHER ◽  
KATHLEEN HENSHILWOOD ◽  
DAVID N. LEES
Keyword(s):  
Human Health Risk ◽  
Extended Period ◽  
Epidemiological Data ◽  
Indicator Organisms ◽  
Fecal Indicator ◽  
E Coli ◽  
Reverse Transcription Pcr ◽  
The United Kingdom ◽  
Male Specific ◽  
Production Areas

The human health risk associated with the consumption of molluscan shellfish grown in sewage-contaminated waters is well established. Noroviruses, which cause gastroenteritis, are the principal agents of shellfish-related illness. Fecal-indicator quality standards based on Escherichia coli are well established in Europe and elsewhere. However, norovirus outbreaks after consumption of shellfish meeting these standards still occur, and the need to improve consumer health protection is well recognized. Alternative approaches proposed include direct monitoring of viral pathogens and the use of alternative indicator organisms capable of providing a better indication of virus risk. This study applies a recently developed TaqMan PCR assay to assess norovirus contamination in shellfish. Comparison was made with E. coli as the existing sanitary standard and a male-specific RNA bacteriophage as a possible alternative. Two commercial pacific oyster (Crassostrea gigas) harvesting areas were monitored over a 31-month period. The results show peaks of norovirus contamination in both areas during winter months, with average levels approximately 17 times higher in oysters sampled October to March than during the remainder of the year, consistent with epidemiological data for the United Kingdom showing oyster-associated illness is confined to winter months. While there was no apparent association with E. coli, an association between levels of norovirus contamination and the male-specific RNA bacteriophage was noted, with average norovirus levels over 40 times higher in samples with male-specific RNA bacteriophage counts of &gt;1,000 PFU/100 g than in samples with &lt;100 PFU/100 g. Overall, these results suggest that norovirus monitoring in shellfish production areas could be an effective strategy for reduction of virus risk.

scholarly journals Quantification of human norovirus GII, human adenovirus, and fecal indicator organisms in wastewater used for irrigation in Accra, Ghana

2013 ◽  
Vol 11 (3) ◽  
pp. 473-488 ◽  
Author(s):  
Andrea I. Silverman ◽  
Mark O. Akrong ◽  
Philip Amoah ◽  
Pay Drechsel ◽  
Kara L. Nelson
Keyword(s):  
Water Reuse ◽  
Wastewater Irrigation ◽  
World Health ◽  
Quantitative Microbial Risk Assessment ◽  
Human Pathogens ◽  
Indicator Organisms ◽  
Fecal Indicator ◽  
E Coli ◽  
Human Viruses ◽  
Human Specific

Quantitative microbial risk assessment (QMRA) is frequently used to estimate health risks associated with wastewater irrigation and requires pathogen concentration estimates as inputs. However, human pathogens, such as viruses, are rarely quantified in water samples, and simple relationships between fecal indicator bacteria and pathogen concentrations are used instead. To provide data that can be used to refine QMRA models of wastewater-fed agriculture in Accra, stream, drain, and waste stabilization pond waters used for irrigation were sampled and analyzed for concentrations of fecal indicator microorganisms (human-specific Bacteroidales, Escherichia coli, enterococci, thermotolerant coliform, and somatic and F+ coliphages) and two human viruses (adenovirus and norovirus genogroup II). E. coli concentrations in all samples exceeded limits suggested by the World Health Organization, and human-specific Bacteroidales was found in all but one sample, suggesting human fecal contamination. Human viruses were detected in 16 out of 20 samples, were quantified in 12, and contained 2–3 orders of magnitude more norovirus than predicted by norovirus to E. coli concentration ratios assumed in recent publications employing indicator-based QMRA. As wastewater irrigation can be beneficial for farmers and municipalities, these results should not discourage water reuse in agriculture, but provide motivation and targets for wastewater treatment before use on farms.

scholarly journals Quantitative assessment of Naegleria fowleri and Escherichia coli concentrations within a Texas reservoir

2013 ◽  
Vol 11 (2) ◽  
pp. 346-357 ◽  
Author(s):  
Stephanie M. Painter ◽  
Russell S. Pfau ◽  
Jeff A. Brady ◽  
Anne M. S. McFarland
Keyword(s):  
Escherichia Coli ◽  
Surface Waters ◽  
Water Samples ◽  
Late Summer ◽  
Naegleria Fowleri ◽  
Fecal Indicator ◽  
E Coli ◽  
Environmental Surface ◽  
Polymerase Chain ◽  
Nægleria Fowleri

Previous presence/absence studies have indicated a correlation between the presence of the pathogenic amoeba Naegleria fowleri and the presence of bacteria, such as the fecal indicator Escherichia coli, in environmental surface waters. The objective of this study was to use quantitative real-time polymerase chain reaction (qPCR) methodologies to measure N. fowleri and E. coli concentrations within a Texas reservoir in late summer, and to determine if concentrations of N. fowleri and E. coli were statistically correlated. N. fowleri was detected in water samples from 67% of the reservoir sites tested, with concentrations ranging up to an estimated 26 CE (cell equivalents)/100 mL. E. coli was detected in water samples from 60% of the reservoir sites tested, with concentrations ranging up to 427 CE/100 mL. In this study, E. coli concentrations were not indicative of N. fowleri concentrations.

Prevalence of Pathogens and Indicator Organisms in Home Kitchens and Correlation with Unsafe Food Handling Practices and Conditions

2017 ◽  
Vol 80 (4) ◽  
pp. 590-597 ◽  
Author(s):  
Patricia A. Borrusso ◽  
Jennifer J. Quinlan
Keyword(s):  
Foodborne Pathogens ◽  
Foodborne Pathogen ◽  
Fecal Coliforms ◽  
Indicator Organisms ◽  
Food Handling ◽  
E Coli ◽  
Handling Practices ◽  
Food Handling Practices ◽  
Multiple Pathogens

ABSTRACT Despite education efforts, consumers often practice unsafe food handling and storage behaviors. Little is known about how these unsafe practices contribute to contamination of the home kitchen with foodborne pathogens. In addition, only a limited number of studies have examined the role of the kitchen as a reservoir for pathogens. The purpose of this study was to characterize microbial contamination and foodborne pathogens found in home kitchens and determine whether contamination was significantly associated with unsafe or unsanitary conditions observed in the kitchen. Swab samples were collected from food contact and preparation surfaces in homes (n = 100) in Philadelphia, PA. The samples were tested for coliforms, fecal coliforms, Escherichia coli, Staphylococcus aureus, Salmonella, Campylobacter, and Listeria. Fecal coliforms were found in 44% of homes (most often in samples from kitchen sinks, sponges, and dishcloths), and E. coli was found in 15% of homes (mostly in samples from kitchen sinks). Nearly half (45%) of the homes tested positive for a foodborne pathogen, and 12% had multiple pathogens present in the kitchen. S. aureus was isolated from 39% of homes, most often from countertops and refrigerator door handles. Listeria spp., including L. monocytogenes and L. innocua, were present in 15% of homes, most often in samples from refrigerator meat drawers. C. jejuni was isolated from 3% of homes. Contamination with Listeria was significantly associated with higher refrigerator temperatures. The contamination of surfaces with fecal coliforms and S. aureus was significantly associated with a lack of cleaning materials: dish soap and paper or cloth towels in the kitchen, and any type of towel in the nearest bathroom. The contamination of a sponge or dishcloth with either fecal coliforms or S. aureus was predictive of other surfaces in the kitchen having the same contamination, indicating that sponges and dishcloths are both reservoirs and vectors for bacteria in the kitchen.

Distribution and Prevalence of Airborne Microorganisms in Three Commercial Poultry Processing Plants

2001 ◽  
Vol 64 (3) ◽  
pp. 388-391 ◽  
Author(s):  
P. WHYTE ◽  
J. D. COLLINS ◽  
K. McGILL ◽  
C. MONAHAN ◽  
H. O'MAHONY
Keyword(s):  
Indicator Organisms ◽  
Salmonella Spp ◽  
Air Samples ◽  
E Coli ◽  
Processing Plants ◽  
Plate Counts ◽  
Poultry Processing ◽  
On Line ◽  
Commercial Poultry ◽  
Campylobacter Spp

Airborne microbial contaminants and indicator organisms were monitored within three poultry processing plants (plants A, B, and C). In total, 15 cubic feet (c.f.) of air was sampled per location during 15 visits to each plant and quantitatively analyzed for total mesophilic and psychrophilic aerobic counts, thermophilic campylobacters, Escherichia coli, and Enterobacteriaceae. The prevalence of Salmonella spp. in air samples was also evaluated. Significant reductions in total aerobic counts were observed between defeathering and evisceration areas of the three plants (P &lt; 0.05). Mesophilic plate counts were highest in the defeathering areas of all plants compared to equivalent psychrophilic plate counts. Enterobacteriaceae counts were highest in the defeathering areas of all three plants with counts of log10 1.63, 1.53, and 1.18 CFU/15 c.f. recovered in plants A, B, and C, respectively. E. coli enumerated from air samples in the defeathering areas exhibited a similar trend to those obtained for Enterobacteriaceae with log10 1.67, 1.58, and 1.18 CFU for plants A, B, and C, respectively. Thermophilic campylobacters were most frequently isolated from samples in the defeathering areas followed by the evisceration areas. The highest mean counts of the organism were observed in plant A at 21 CFU/15 c.f. sample with plants B and C at 9 and 8 CFU/sample, respectively. With the exception of low levels of Enterobacteriaceae recovered from samples in the on-line air chill in plant A, E. coli, Enterobacteriaceae, or Campylobacter spp. were not isolated from samples in postevisceration sites in any of the plants examined. Salmonella spp. were not recovered from any samples during the course of the investigation.

scholarly journals Pathogen and indicator variability in a heavily impacted watershed

2007 ◽  
Vol 5 (2) ◽  
pp. 241-257 ◽  
Author(s):  
Sarah M. Dorner ◽  
William B. Anderson ◽  
Terri Gaulin ◽  
Heather L. Candon ◽  
Robin M. Slawson ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Rank Correlation ◽  
Fecal Coliforms ◽  
Escherichia Coli O157 ◽  
Indicator Organisms ◽  
Transport Models ◽  
E Coli ◽  
Thermophilic Campylobacter ◽  
Spearman Rank Correlation Test ◽  
Campylobacter Spp

Water samples were collected from 36 locations within the Grand River Watershed, in Southwestern Ontario, Canada from July 2002 to December 2003 and were analyzed for total coliforms, fecal coliforms, Escherichia coli, Escherichia coli O157:H7, and thermophilic Campylobacter spp. A subset of samples was also analyzed for Cryptosporidium spp., Giardia spp., culturable human enteric viruses, and Clostridium perfringens. Storm and snowmelt events were sampled at two locations including a drinking water intake. For the majority of the events, the Spearman rank correlation test showed a positive correlation between E. coli levels and turbidity. Peaks in pathogen numbers frequently preceded the peaks in numbers of indicator organisms and turbidity. Pathogen levels sometimes decreased to undetectable levels during an event. As pathogen peaks did not correspond to turbidity and indicator peaks, the correlations were weak. Weak correlations may be the result of differences in the sources of the pathogens, rather than differences in pathogen movement through the environment. Results from this investigation have implications for planning monitoring programs for water quality and for the development of pathogen fate and transport models to be used for source water risk assessment.

Decontamination of Beef Carcass Surface Tissue by Steam Vacuuming Alone and Combined with Hot Water and Lactic Acid Sprays

1999 ◽  
Vol 62 (2) ◽  
pp. 146-151 ◽  
Author(s):  
A. CASTILLO ◽  
L. M. LUCIA ◽  
K. J. GOODSON ◽  
J. W. SAVELL ◽  
G. R. ACUFF
Keyword(s):  
Lactic Acid ◽  
Combined Treatment ◽  
Hot Water ◽  
Contaminated Sites ◽  
Indicator Organisms ◽  
E Coli ◽  
Cleaning System ◽  
Plate Counts ◽  
Thermotolerant Coliforms ◽  
Beef Carcass

Hot beef carcass surface regions (outside round, brisket, and clod) contaminated with feces spread over a 5-cm2 (1-in2) area were cleaned using a steam-vacuum spot-cleaning system alone or combined with subsequent sanitizing treatments of hot water (95°C at the nozzle), or warm (55°C) 2% lactic acid spray, or combinations of these two sanitizing methods. These treatments were compared for effectiveness in reducing aerobic plate counts (APC) and counts of Enterobacteriaceae, total coliforms, thermotolerant coliforms, and Escherichia coli. All treatments significantly reduced the numbers of each group of bacteria on beef carcass surfaces. However, reductions obtained by steam vacuuming were significantly smaller than those obtained by a combination of steam vacuuming with any sanitizing treatment. No differences in bacterial reductions were observed between different carcass surface regions. Steam vacuuming reduced the number of different indicator organisms tested by ca. 3.0 log cycles but also spread the bacterial contamination to areas of the carcass surface adjacent to the contaminated sites. This relocated contamination after steam vacuuming was most effectively reduced by spraying with hot water and then lactic acid. This combined treatment consistently reduced the numbers of Enterobacteriaceae, total and thermotolerant coliforms, and E. coli to undetectable levels (&lt;1.0 log10 CFU/cm2) on areas outside the initial 5-cm2 inoculated areas.

scholarly journals Estimation of concentration ratio of indicator to pathogen-related gene in environmental water based on left-censored data

2015 ◽  
Vol 14 (1) ◽  
pp. 14-25 ◽  
Author(s):  
Tsuyoshi Kato ◽  
Ayano Kobayashi ◽  
Toshihiro Ito ◽  
Takayuki Miura ◽  
Satoshi Ishii ◽  
...  
Keyword(s):  
Genetic Markers ◽  
Censored Data ◽  
Concentration Ratio ◽  
Virulence Gene ◽  
Environmental Water ◽  
Fecal Indicator ◽  
E Coli ◽  
Positive Rate ◽  
Identical Number ◽  
Analytical Quantification

A stochastic model for estimating the ratio between a fecal indicator and a pathogen based on left-censored data, which includes a substantially high number of non-detects, was constructed. River water samples were taken for 16 months at six points in a river watershed, and conventional fecal indicators (total coliforms and general Escherichia coli), genetic markers (Bacteroides spp.), and virulence genes (eaeA of enteropathogenic E. coli and ciaB of Campylobacter jejuni) were quantified. The quantification of general E. coli failed to predict the presence of the virulence gene from enteropathogenic E. coli, different from what happened with genetic markers (Total Bac and Human Bac). A Bayesian model that was adapted to left-censored data with a varying analytical quantification limit was applied to the quantitative data, and the posterior predictive distributions of the concentration ratio were predicted. When the sample size was 144, simulations conducted in this study suggested that 39 detects were enough to accurately estimate the distribution of the concentration ratio, when combined with a dataset with a positive rate higher than 99%. To evaluate the level of accuracy in the estimation, it is desirable to perform a simulation using an artificially generated left-censored dataset that has the identical number of non-detects as the actual data.

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