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.

Survival and Growth of Listeria monocytogenes and Enterohemorrhagic Escherichia coli O157:H7 in Minimally Processed Artichokes

2003 ◽  
Vol 66 (12) ◽  
pp. 2203-2209 ◽  
Author(s):  
SUSANA SANZ ◽  
MERCEDES GIMÉNEZ ◽  
CARMEN OLARTE
Keyword(s):  
Escherichia Coli ◽  
Listeria Monocytogenes ◽  
Tap Water ◽  
Storage Period ◽  
Enterohemorrhagic Escherichia Coli ◽  
Fecal Coliforms ◽  
Escherichia Coli O157 ◽  
Natural Background ◽  
Minimally Processed ◽  
E Coli

The ability of Listeria monocytogenes and Escherichia coli O157:H7 inoculated by immersion (at 4.6 and 5.5 log CFU/g, respectively) to survive on artichokes during various stages of preparation was determined. Peeling, cutting, and disinfecting operations (immersion in 50 ppm of a free chlorine solution at 4°C for 5 min) reduced populations of L. monocytogenes and E. coli O157:H7 by only 1.6 and 0.8 log units, respectively. An organic acid rinse (0.02% citric acid and 0.2% ascorbic acid) was more effective than a tap water rinse in removing these pathogens. Given the possibility of both pathogens being present on artichokes at the packaging stage, their behavior during the storage of minimally processed artichokes was investigated. For this purpose, batches of artichokes inoculated with L. monocytogenes or E. coli O157:H7 (at 5.5 and 5.2 log CFU/g, respectively) were packaged in P-Plus film bags and stored at 4°C for 16 days. During this period, the equilibrium atmosphere composition and natural background microflora (mesophiles, psychrotrophs, anaerobes, and fecal coliforms) were also analyzed. For the two studied pathogens, the inoculum did not have any effect on the final atmospheric composition (10% O2, 13% CO2) or on the survival of the natural background microflora of the artichokes. L. monocytogenes was able to survive during the entire storage period in the inoculated batches, while the E. coli O157:H7 level increased by 1.5 log units in the inoculated batch during the storage period. The modified atmosphere was unable to control the behavior of either pathogen.

Fate of Naturally Occurring Escherichia coli O157:H7 and Other Zoonotic Pathogens during Minimally Managed Bovine Feedlot Manure Composting Processes†

2013 ◽  
Vol 76 (8) ◽  
pp. 1308-1321 ◽  
Author(s):  
ELAINE D. BERRY ◽  
PATRICIA D. MILLNER ◽  
JAMES E. WELLS ◽  
NORASAK KALCHAYANAND ◽  
MICHAEL N. GUERINI
Keyword(s):  
Escherichia Coli ◽  
Listeria Monocytogenes ◽  
High Temperatures ◽  
Thermophilic Bacteria ◽  
Foodborne Illness ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Naturally Occurring ◽  
On Farm ◽  
Campylobacter Spp

Reducing Escherichia coli O157:H7 in livestock manures before application to cropland is critical for reducing the risk of foodborne illness associated with produce. Our objective was to determine the fate of naturally occurring E. coli O157:H7 and other pathogens during minimally managed on-farm bovine manure composting processes. Feedlot pen samples were screened to identify E. coli O157:H7–positive manure. Using this manure, four piles of each of three different composting formats were constructed in each of two replicate trials. Composting formats were (i) turned piles of manure plus hay and straw, (ii) static stockpiles of manure, and (iii) static piles of covered manure plus hay and straw. Temperatures in the tops, toes, and centers of the conical piles (ca. 6.0 m3 each) were monitored. Compost piles that were turned every 2 weeks achieved higher temperatures for longer periods in the tops and centers than did piles that were left static. E. coli O157:H7 was not recovered from top samples of turned piles of manure plus hay and straw at day 28 and beyond, but top samples from static piles were positive for the pathogen up to day 42 (static manure stockpiles) and day 56 (static covered piles of manure plus hay and straw). Salmonella, Campylobacter spp., and Listeria monocytogenes were not found in top or toe samples at the end of the composting period, but E. coli O157:H7 and Listeria spp. were recovered from toe samples at day 84. Our findings indicate that some minimally managed composting processes can reduce E. coli O157:H7 and other pathogens in bovine manure but may be affected by season and/or initial levels of indigenous thermophilic bacteria. Our results also highlight the importance of adequate C:N formulation of initial mixtures for the production of high temperatures and rapid composting, and the need for periodic turning of the piles to increase the likelihood that all parts of the mass are subjected to high temperatures.

Risk of Escherichia coli O157:H7, Non-O157 Shiga Toxin–Producing Escherichia coli, and Campylobacter spp. in Food Animals and Their Products in Qatar

2015 ◽  
Vol 78 (10) ◽  
pp. 1812-1818 ◽  
Author(s):  
HUSSNI O. MOHAMMED ◽  
KORANA STIPETIC ◽  
AHMED SALEM ◽  
PATRICK McDONOUGH ◽  
YUNG FU CHANG ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Cross Sectional Study ◽  
Campylobacter Coli ◽  
Escherichia Coli O157 ◽  
Cross Sectional ◽  
Fecal Samples ◽  
E Coli ◽  
Cattle Feces ◽  
Campylobacter Spp

Escherichia coli O157:H7, non-O157 E. coli, and Campylobacter spp. are among the top-ranked pathogens that threaten the safety of food supply systems around the world. The associated risks and predisposing factors were investigated in a dynamic animal population using a repeat-cross-sectional study design. Animal and environmental samples were collected from dairy and camel farms, chicken processing plants, and abattoirs and analyzed for the presence of these pathogens using a combination of bacterial enrichment and real-time PCR tests without culture confirmation. Data on putative risk factors were also collected and analyzed. E. coli O157:H7 was detected by PCR at higher levels in sheep and camel feces than in cattle feces (odds ratios [OR], 6.8 and 21.1, respectively). Although the genes indicating E. coli O157:H7 were detected at a relatively higher rate (4.3%) in fecal samples from dairy cattle, they were less common in milk and udder swabs from the same animals (1 and 2%, respectively). Among the food adulterants, E. coli O103 was more common in cattle fecal samples, whereas O26 was more common in sheep feces and O45 in camel feces compared with cattle (OR, 2.6 and 3.1, respectively). The occurrence of E. coli in the targeted populations differed by the type of sample and season of the year. Campylobacter jejuni and Campylobacter coli were more common in sheep and camel feces than in cattle feces. Most of the survey and surveillance of E. coli focused on serogroup O157 as a potential foodborne hazard; however, based on the PCR results, non-O157 Shiga toxin–producing E. coli serotypes appeared to be more common, and efforts should be made to include them in food safety programs.

Temporal Patterns and Risk Factors for Escherichia coli O157 and Campylobacter spp. in Young Cattle

2009 ◽  
Vol 72 (3) ◽  
pp. 490-496 ◽  
Author(s):  
JOHANNE ELLIS-IVERSEN ◽  
ALASDAIR J. C. COOK ◽  
RICHARD P. SMITH ◽  
GEOFF C. PRITCHARD ◽  
MIRJAM NIELEN
Keyword(s):  
Risk Factors ◽  
Escherichia Coli ◽  
Management Practices ◽  
Linear Trend ◽  
Farm Animals ◽  
Escherichia Coli O157 ◽  
Herd Prevalence ◽  
E Coli ◽  
Young Cattle ◽  
Campylobacter Spp

Escherichia coli O157 and Campylobacter jejuni and Campylobacter coli are zoonotic pathogens originating from farm animals. Cattle are the main reservoir for E. coli O157 and also contribute to human cases of campylobacteriosis through contaminated milk, direct contact, and environmental contamination. Thirty groups of young cattle on 30 farms were observed for 7 months and sampled on 4 to 6 separate occasions for E. coli O157 and C. jejuni/coli to characterize shedding patterns and identify risk factors. The within herd prevalence of E. coli O157 per sampling occasion ranged from 0 to 60% (mean = 24%) and average Campylobacter spp. within herd prevalence was 47% ranging from 0 to 100%. The prevalence of E. coli O157–positive herds declined with a linear trend throughout the study from 100 to 38% (OR: 0.5, P < 0.01), whereas time in the study was not significantly associated with Campylobacter prevalence (P = 0.13). Larger herds were more likely to be positive with either or both agents, whereas the number of suckler calves on the farm reduced the risk of both organisms (OR: 0.4/0.6, P < 0.01). Poultry on the premises reduced the risk of E. coli O157, but was not associated with Campylobacter. Emptying and cleaning the water troughs more often than once monthly reduced the risk of detecting Campylobacter and cattle sourced by private water supplies were more likely to be Campylobacter positive. No drinking water management practices were associated with E. coli O157. The risk of detecting both organisms were almost five times higher when the cattle were housed indoors (OR: 4.9, P = 0.03).

Prevalence of Escherichia coli O157:H7 and Indicator Organisms on the Surface of Intact Subprimal Beef Cuts Prior to Further Processing

2006 ◽  
Vol 69 (7) ◽  
pp. 1514-1517 ◽  
Author(s):  
JAMES E. KENNEDY ◽  
SALLY K. WILLIAMS ◽  
TED BROWN ◽  
PHIL MINERICH
Keyword(s):  
Escherichia Coli ◽  
Total Coliform ◽  
Escherichia Coli O157 ◽  
Indicator Organisms ◽  
Seasonal Differences ◽  
Total Coliforms ◽  
E Coli ◽  
Plate Counts ◽  
Collection Period

The objective of this study was to determine the prevalence of Escherichia coli O157:H7, other E. coli strains, total coliforms, and aerobic organisms on the surface of subprimal beef cuts prior to enhancement. Subprimal cuts were sampled during winter (January and February 2004) and summer (August through October 2004). During each collection period, six representative subprimal cuts (chuck tenders, 0.64-cm trimmed strips, bottom round flat, rough-trimmed brisket, cap-on top rounds, and cap-off insides) were sampled. A total of 600 samples in winter (100 samples per cut) and 599 samples in summer (100 chuck tenders, 100 0.64-cm trimmed strips, 100 bottom round flats, 100 cap-off insides, 97 rough-trimmed briskets, and 102 cap-on top rounds) were collected from five plants in the Midwest, southern Midwest, northern Midwest, and Southeast and swabbed using the sponge swab method. All sponges were analyzed for E. coli O157:H7. In addition, 400 subprimal cuts from four plants were analyzed for aerobic plate counts, total coliforms, and other E. coli strains during each collection period. E. coli O157:H7 was not detected on any of the 1,199 subprimal samples; thus, incidence of E. coli O157:H7 was <0.083%. Seasonal differences between aerobic plate counts and total coliform counts for each of the same cuts were 1.0 log CFU per cut or less. E. coli strains were not detected in 82, 52, 69, and 82% of the chuck tenders, 0.64-cm trimmed strips, bottom round flats, and cap-off insides, respectively.

Potential for the Spread of Escherichia coli O157, Salmonella, and Campylobacter in the Lairage Environment at Abattoirs

2002 ◽  
Vol 65 (6) ◽  
pp. 931-936 ◽  
Author(s):  
A. SMALL ◽  
C.-A. REID ◽  
S. M. AVERY ◽  
N. KARABASIL ◽  
C. CROWLEY ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Animal Movement ◽  
Contaminated Sites ◽  
Escherichia Coli O157 ◽  
Salmonella Spp ◽  
E Coli ◽  
Meat Safety ◽  
Pathogen Control ◽  
Safety Systems ◽  
Campylobacter Spp

Prevalences of Escherichia coli O157, Salmonella spp., and Campylobacter spp. were examined in 270 swabs taken from selected sites along the unloading-to-slaughter routes of animal movement in lairages of six commercial abattoirs, three for cattle and three for sheep. The overall prevalences of the pathogens in the respective lairage environments were compared with those for 270 swabs from the pelts of 90 lambs examined in the present study and 270 swabs from the hides of 90 cattle examined in a previous study that were slaughtered at the same abattoirs on the same days. Also, the results obtained were analyzed with the aim of identifying critical points at which animal-environment-animal transfer of the pathogens in lairages occurs. The results showed that (i) the overall prevalences of E. coli O157, Salmonella spp., and Campylobacter spp. were 27.2, 6.1, and 1.1%, respectively, in cattle lairages and 2.2, 1.1, and 5.6%, respectively, in sheep lairages; (ii) the overall prevalences of the three pathogens on cow hides (28.8, 17.7, and 0%, respectively) and sheep pelts (5.5, 7.8, and 0%, respectively) were higher than the overall prevalences in the respective lairage environments; (iii) the most frequently contaminated sites in cattle lairages were holding pen floors (50% of swabs positive for one or more pathogens), entrance gates of stun boxes (27.8% of swabs positive for one or more pathogens), and stun box floors (22.2% of swabs positive for one or more pathogens); (iv) the most frequently contaminated sites in sheep lairages were unloading ramp floors, holding pen floors, and water troughs (33.3, 22.2, and 22.2%, respectively); and (v) overall, cattle lairages and cow hides were more frequently contaminated with the pathogens than were lamb lairages and lamb pelts. Further research is needed to develop strategies for the incorporation of pathogen control in lairages into integrated microbial meat safety systems.

Factors affecting the occurrence of Escherichia coli O157 contamination in irrigation ponds on produce farms in the Suwannee River Watershed

2013 ◽  
Vol 59 (3) ◽  
pp. 175-182 ◽  
Author(s):  
Ganyu Gu ◽  
Zhiyao Luo ◽  
Juan M. Cevallos-Cevallos ◽  
Paige Adams ◽  
George Vellidis ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Environmental Factors ◽  
Water Samples ◽  
Fecal Coliforms ◽  
Subsurface Water ◽  
Escherichia Coli O157 ◽  
Culturable Bacteria ◽  
River Watershed ◽  
E Coli ◽  
Suwannee River

Outbreaks of enteritis caused by Escherichia coli O157 associated with fresh produce have resulted in questions about the safety of irrigation water; however, associated risks have not been systematically evaluated. In this study, the occurrence and distribution of the human pathogen E. coli O157 from vegetable irrigation ponds within the Suwannee River Watershed in Georgia were investigated, and the relationship to environmental factors was analyzed. Surface and subsurface water samples were collected monthly from 10 vegetable irrigation ponds from March 2011 to February 2012. Escherichia coli O157 was isolated from enriched filtrates on CHROMagar and sorbitol MacConkey agar media and confirmed by an agglutination test. Presence of virulence genes stx1, stx2 , and eae was tested by polymerase chain reaction. In addition, 27 environmental variables of the sampled ponds were measured. Denaturing gradient gel electrophoresis was conducted for the analysis of bacterial communities in the water samples. Biserial correlation coefficients were calculated to evaluate the log10 colony-forming unit per millilitre correlations between the environmental factors and the occurrence of E. coli O157. Stepwise and canonical discriminant analyses were used to determine the factors that were associated with the presence and absence of E. coli O157 in water samples. All 10 ponds were positive for E. coli O157 some of the time, mainly in summer and fall of 2011. The temporal distribution of this bacterium differed among the 10 ponds. Temperature, rainfall, populations of fecal coliform, and culturable bacteria were positively correlated with the occurrence of E. coli O157 (P < 0.05), while the total nitrogen concentration, oxidation–reduction potential, and dissolved oxygen concentration were negatively correlated with the occurrence of this pathogen (P < 0.05). Temperature and rainfall were the most important factors contributing to the discrimination between samples with and without E. coli O157, followed by bacterial diversity and culturable bacteria population density. Bacterial numbers and diversity, including fecal coliforms and E. coli O157, increased after rainfall (and possibly runoff from pond margins) in periods with relatively high temperatures, suggesting that prevention of runoff may be important to minimize the risk of enteric pathogens in irrigation ponds.

scholarly journals Escherichia coli O157 Prevalence and Enumeration of Aerobic Bacteria, Enterobacteriaceae, and Escherichia coli O157 at Various Steps in Commercial Beef Processing Plants†

2004 ◽  
Vol 67 (4) ◽  
pp. 658-665 ◽  
Author(s):  
TERRANCE M. ARTHUR ◽  
JOSEPH M. BOSILEVAC ◽  
XIANGWU NOU ◽  
STEVEN D. SHACKELFORD ◽  
TOMMY L. WHEELER ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Aerobic Bacteria ◽  
Escherichia Coli O157 ◽  
Indicator Organisms ◽  
E Coli ◽  
Beef Processing ◽  
Processing Plants ◽  
Plate Counts ◽  
On Line ◽  
Antimicrobial Interventions

The effectiveness of current antimicrobial interventions used in reducing the prevalence or load of Escherichia coli O157 and indicator organisms on cattle hides and carcasses at two commercial beef processing plants was evaluated. Sponge sampling of beef cattle was performed at five locations from the initial entry of the animals to the slaughter floor to the exit of carcasses from the “hotbox” cooler. For each sample, E. coli O157 prevalence was determined and total aerobic bacteria, Enterobacteriaceae, and E. coli O157 were enumerated. E. coli O157 was found on 76% of animal hides coming into the plants, but no carcasses leaving the cooler were identified as contaminated with E. coli O157. A positive relationship was seen between the incidence of E. coli O157 in hide samples and that in preevisceration samples. Aerobic plate counts and Enterobacteriaceae counts averaged 7.8 and 6.2 log CFU/100 cm2, respectively, on hides, and 1.4 and 0.4 log CFU/100 cm2, respectively, on chilled carcasses. Aerobic plate counts and Enterobacteriaceae counts on preevisceration carcasses were significantly related to the respective levels on the corresponding hides; the carcasses of animals whose hides carried higher numbers of bacteria were more likely to carry higher numbers of bacteria. Implementation of the sampling protocol described here would allow processors to evaluate the efficacy of on-line antimicrobial interventions and allow industrywide benchmarking of hygienic practices.

Prevalence and Antimicrobial Resistance Profiles of Escherichia coli O157:H7 and Salmonella Isolated from Feedlot Lambs†

2009 ◽  
Vol 72 (8) ◽  
pp. 1713-1717 ◽  
Author(s):  
TOM S. EDRINGTON ◽  
MELISSA LONG ◽  
TIM T. ROSS ◽  
JACK D. THOMAS ◽  
TODD R. CALLAWAY ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Multidrug Resistant ◽  
Fecal Coliforms ◽  
Processing Plant ◽  
Escherichia Coli O157 ◽  
Fecal Samples ◽  
E Coli ◽  
Feedlot Lambs ◽  
Plant Processing ◽  
Carcass Contamination

The present study examined the incidence of Escherichia coli O157:H7 and Salmonella in feedlot lambs. Fifty-six feedlot lambs from eight sheep farming operations were grouped in a single drylot pen, fed, and managed as is typical in the southwestern United States. Fecal samples were collected on days 0, 46, 87, and 122 of the feeding period via rectal palpation. Wool samples (ventral midline) were collected one time only at the feedlot, immediately prior to shipping to the processing plant, and carcass swabs were collected following slaughter. All samples were cultured for E. coli O157:H7, Salmonella, and fecal coliforms, and select isolates were examined for antimicrobial susceptibility. Overall, the percentages of fecal and wool samples positive for E. coli O157:H7 averaged 9 and 18%, respectively. One carcass swab was E. coli O157:H7 positive. Of the 155 fecal samples collected, 11 (7%) were Salmonella positive. Salmonella was detected in nearly 50% of the wool samples collected prior to slaughter, while none of the carcasses were Salmonella positive 24 h postslaughter. All isolates (E. coli O157:H7, Salmonella, and fecal coliforms) were susceptible to ceftiofur, enrofloxacin, and trimethoprim-sulfamethoxazole. One E. coli O157:H7 isolate cultured from a carcass swab was resistant to seven antibiotics, and seven wool E. coli O157: H7 isolates were multidrug resistant. Results of this research demonstrate that feedlot sheep are naturally colonized with E. coli O157:H7 and Salmonella and wool can be a source of carcass contamination; however, in-plant processing procedures and intervention strategies were largely effective in preventing carcass contamination.

Bacteriologic Quality of Some Trinidadian Ready-to-Consume Foods and Drinks and Possible Health Risks to Consumers

1995 ◽  
Vol 58 (6) ◽  
pp. 651-655 ◽  
Author(s):  
A. A. ADESIYUN
Keyword(s):  
Escherichia Coli ◽  
Health Risks ◽  
Food Source ◽  
Food Samples ◽  
Salmonella Spp ◽  
E Coli ◽  
Thermophilic Campylobacter ◽  
The Difference ◽  
Campylobacter Spp

The bacteriologic quality of 10 ready-to-consume Trinidadian foods and drinks was determined by culturing for Staphylococcus aureus, Escherichia coli, Salmonella spp. and thermophilic Campylobacter spp. The toxigenicity of S. aureus and E. coli strains was determined and the susceptibility of S. aureus isolates to bacteriophages was also investigated. Of a total of 293 food samples tested, 58 (19.8%), 30 (10.2%), and 10 (3.4%) were positive for S. aureus, E. coli, and Salmonella spp., respectively. All samples were negative for Campylobacter but only two food types, chutney and preserved fruits, were negative in all pathogen assays. The sausage known as black pudding (boudin noir) was significantly (P ≤ 0.001; χ2 more contaminated with S. aureus (73.0%) than other foods and was also significantly (P ≤ 0.0l; χ2) more contaminated (43.2%) than all other foods except seamoss (33.3%) and roti (20.0%), where the difference was not significant (P ≥ 0.05; χ2). Black pudding also yielded all 10 strains of Salmonella isolated; the prevalent serotypes were S. agona (4 isolates) and S. derby (3 isolates). All 30 isolates of E. coli were negative for heat-labile enterotoxins (LT) and verotoxins (VT). Of the 58 S. aureus isolates, 33 (56.9%) were susceptible to bacteriophages with 19 (70.4%) of 20 black-pudding and 12 (66.7%) of 18 ice-cream isolates typeable. None of the isolates recovered from local sweets, snow cones, and roti was typeable. Regardless of the food source, strains of S. aureus were most susceptible to phages in various groups (mixed) constituting 21 (63.6%) of 33 strains typeable, followed by phages in groups III (18.2%) and V (15.2%). Twenty-two (37.9%) strains of S. aureus were enterotoxigenic with 8 (13.8%), 5 (8.6%), 13 (22.4%), and 12 (20.7%) strains producing, either singly or mixed, Staphylococcal enterotoxins A(SEA), B(SEB), C(SEC), and D(SED) respectively. It was concluded that black pudding, a local delicacy, poses the greatest health risk to consumers, making it imperative to institute sanitary measures during its production and sale.

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