Changes in Presence of Shiga Toxin-Producing Escherichia Coli (Stec) and Salmonella Spp. in Very Small Honduran Beef Processing Plants after Personnel Training in Food Safety Practices

Several antimicrobial compounds have been used in commercial meat processing plants for decontamination of pathogens on beef carcasses, but there are many commercially available, novel antimicrobial compounds that may be more effective and suitable for use in beef processing pathogen-reduction programs. Sixty-four prerigor beef flanks (cutaneous trunci) were used in a study to determine whether hypobromous acid, neutral acidified sodium chlorite, and two citric acid–based antimicrobial compounds effectively reduce seven Shiga toxin–producing Escherichia coli (STEC) serogroups and Salmonella on the surface of fresh beef. Two cocktail mixtures were inoculated onto prerigor beef flank surfaces. Cocktail mixture 1 was composed of STEC serogroups O26, O103, O111, O145, and O157; and cocktail mixture 2 was composed of STEC serogroups O45, O121, and O157 and Salmonella. The inoculated fresh beef flanks were subjected to spray treatments with four antimicrobial compounds. Following antimicrobial treatments, both control and treated fresh beef samples were either enumerated immediately or were stored for 48 h at 4°C before enumeration. All four antimicrobial compounds caused 0.7- to 2.0-log reductions of STEC, Salmonella, aerobic plate counts, and Enterobacteriaceae. Results also indicated that the four antimicrobial compounds were as effective at reducing the six non-O157 STEC strains as they were at reducing E. coli O157:H7 on the surfaces of fresh beef. The recovery of all seven STEC strains and Salmonella in a low-inoculation study indicated that none of the four antimicrobial compounds eliminated all of the tested pathogens.

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Seasonal Prevalence of Shiga Toxin–Producing Escherichia coli, Including O157:H7 and Non-O157 Serotypes, and Salmonella in Commercial Beef Processing Plants†

Journal of Food Protection ◽

10.4315/0362-028x-66.11.1978 ◽

2003 ◽

Vol 66 (11) ◽

pp. 1978-1986 ◽

Cited By ~ 314

Author(s):

GENEVIEVE A. BARKOCY-GALLAGHER ◽

TERRANCE M. ARTHUR ◽

MILDRED RIVERA-BETANCOURT ◽

XIANGWU NOU ◽

STEVEN D. SHACKELFORD ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Escherichia Coli O157 ◽

Seasonal Prevalence ◽

Fecal Samples ◽

E Coli ◽

Beef Processing ◽

Beef Carcasses ◽

Processing Plants ◽

Antimicrobial Interventions

The seasonal prevalence of Escherichia coli O157:H7, Salmonella, non-O157 E. coli (STEC), and stx-harboring cells was monitored at three Midwestern fed-beef processing plants. Overall, E. coli O157:H7 was recovered from 5.9% of fecal samples, 60.6% of hide samples, and 26.7% of carcasses sampled before the preevisceration wash. This pathogen also was recovered from 1.2% (15 of 1,232) of carcasses sampled at chilling (postintervention) at approximate levels of <3.0 cells per 100 cm2. In one case, the E. coli O157:H7 concentration dropped from ca. 1,100 cells per 320 cm2 at the preevisceration stage to a level that was undetectable on ca. 2,500 cm2 at the postintervention stage. The prevalence of E. coli O157:H7 in feces peaked in the summer, whereas its prevalence on hide was high from the spring through the fall. Overall, Salmonella was recovered from 4.4, 71.0, and 12.7% of fecal, hide, and preevisceration carcass samples, respectively. Salmonella was recovered from one postintervention carcass (of 1,016 sampled). Salmonella prevalence peaked in feces in the summer and was highest on hide and preevisceration carcasses in the summer and the fall. Non-O157 STEC prevalence also appeared to vary by season, but the efficiency in the recovery of isolates from stx-positive samples ranged from 37.5 to 83.8% and could have influenced these results. Cells harboring stx genes were detected by PCR in 34.3, 92.0, 96.6, and 16.2% of fecal, hide, preevisceration carcass, and postintervention carcass samples, respectively. The approximate level of non-O157 STEC and stx-harboring cells on postintervention carcasses was ≥3.0 cells per 100 cm2 for only 8 of 199 carcasses (4.0%). Overall, the prevalence of E. coli O157:H7, Salmonella, and non-O157 STEC varied by season, was higher on hides than in feces, and decreased dramatically, along with pathogen levels, during processing and during the application of antimicrobial interventions. These results demonstrate the effectiveness of the current interventions used by the industry and highlight the significance of hides as a major source of pathogens on beef carcasses.

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Prevalence and Characterization of Non-O157 Shiga Toxin-Producing Escherichia coli on Carcasses in Commercial Beef Cattle Processing Plants

Applied and Environmental Microbiology ◽

10.1128/aem.68.10.4847-4852.2002 ◽

2002 ◽

Vol 68 (10) ◽

pp. 4847-4852 ◽

Cited By ~ 87

Author(s):

Terrance M. Arthur ◽

Genevieve A. Barkocy-Gallagher ◽

Mildred Rivera-Betancourt ◽

Mohammad Koohmaraie

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Human Disease ◽

The United States ◽

E Coli ◽

Beef Processing ◽

Processing Plants ◽

Antimicrobial Interventions ◽

Reported Data ◽

Beef Carcass

ABSTRACT Beef carcass sponge samples collected from July to August 1999 at four large processing plants in the United States were surveyed for the presence of non-O157 Shiga toxin-producing Escherichia coli (STEC). Twenty-eight (93%) of 30 single-source lots surveyed included at least one sample containing non-O157 STEC. Of 334 carcasses sampled prior to evisceration, 180 (54%) were found to harbor non-O157 STEC. Non-O157 STEC isolates were also recovered from 27 (8%) of 326 carcasses sampled after the application of antimicrobial interventions. Altogether, 361 non-O157 STEC isolates, comprising 41 different O serogroups, were recovered. O serogroups that previously have been associated with human disease accounted for 178 (49%) of 361 isolates. Although 40 isolates (11%) carried a combination of virulence factor genes (enterohemorrhagic E. coli hlyA, eae, and at least one stx gene) frequently associated with STEC strains causing severe human disease, only 12 of these isolates also belonged to an O serogroup previously associated with human disease. Combining previously reported data on O157-positive samples (R. O. Elder, J. E. Keen, G. R. Siragusa, G. A. Barkocy-Gallagher, M. Koohmaraie, and W. W. Laegreid, Proc. Natl. Acad. Sci. USA 97:2999-3003, 2000) with these data regarding non-O157-positive samples indicated total STEC prevalences of 72 and 10% in preevisceration and postprocessing beef carcass samples, respectively, showing that the interventions used by the beef-processing industry effected a sevenfold reduction in carcass contamination by STEC.

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Occurrence of Campylobacter spp., Salmonella spp. and shiga toxin‐producing Escherichia coli in inline milk filters from Swedish dairy farms

Journal of Food Safety ◽

10.1111/jfs.12726 ◽

2019 ◽

Vol 40 (1) ◽

Author(s):

Catarina Flink ◽

Karin Nyberg

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Dairy Farms ◽

Salmonella Spp ◽

Swedish Dairy ◽

Campylobacter Spp

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Effect of Exposure Time and Organic Matter on Efficacy of Antimicrobial Compounds against Shiga Toxin–Producing Escherichia coli and Salmonella

Journal of Food Protection ◽

10.4315/0362-028x.jfp-15-204 ◽

2016 ◽

Vol 79 (4) ◽

pp. 561-568 ◽

Cited By ~ 5

Author(s):

NORASAK KALCHAYANAND ◽

MOHAMMAD KOOHMARAIE ◽

TOMMY L. WHEELER

Keyword(s):

Escherichia Coli ◽

Organic Matter ◽

Lactic Acid ◽

Exposure Time ◽

Shiga Toxin ◽

Peracetic Acid ◽

Antimicrobial Compounds ◽

Number Of Factors ◽

Hypobromous Acid ◽

Processing Plants

ABSTRACT Several antimicrobial compounds are in commercial meat processing plants for pathogen control on beef carcasses. However, the efficacy of the method used is influenced by a number of factors, such as spray pressure, temperature, type of chemical and concentration, exposure time, method of application, equipment design, and the stage in the process that the method is applied. The objective of this study was to evaluate effectiveness of time of exposure of various antimicrobial compounds against nine strains of Shiga toxin–producing Escherichia coli (STEC) and four strains of Salmonella in aqueous antimicrobial solutions with and without organic matter. Non-O157 STEC, STEC O157:H7, and Salmonella were exposed to the following aqueous antimicrobial solutions with or without beef purge for 15, 30, 60, 120, 300, 600, and 1,800 s: (i) 2.5% lactic acid, (ii) 4.0% lactic acid, (iii) 2.5% Beefxide, (iv) 1% Aftec 3000, (v) 200 ppm of peracetic acid, (vi) 300 ppm of hypobromous acid, and (vii) water as a control. In general, increasing exposure time to antimicrobial compounds significantly (P ≤ 0.05) increased the effectiveness against pathogens tested. In aqueous antimicrobial solutions without organic matter, both peracetic acid and hypobromous acid were the most effective in inactivating populations of STEC and Salmonella, providing at least 5.0-log reductions with exposure for 15 s. However, in antimicrobials containing organic matter, 4.0% lactic acid was the most effective compound in reducing levels of STEC and Salmonella, providing 2- to 3-log reductions with exposure for 15 s. The results of this study indicated that organic matter and exposure time influenced the efficacy of antimicrobial compounds against pathogens, especially with oxidizer compounds. These factors should be considered when choosing an antimicrobial compound for an intervention.

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Mexican unpasteurised fresh cheeses are contaminated with Salmonella spp., non-O157 Shiga toxin producing Escherichia coli and potential uropathogenic E. coli strains: A public health risk

International Journal of Food Microbiology ◽

10.1016/j.ijfoodmicro.2016.08.018 ◽

2016 ◽

Vol 237 ◽

pp. 10-16 ◽

Cited By ~ 26

Author(s):

Rosa Guzman-Hernandez ◽

Araceli Contreras-Rodriguez ◽

Rosa Hernandez-Velez ◽

Iza Perez-Martinez ◽

Ahide Lopez-Merino ◽

...

Keyword(s):

Public Health ◽

Escherichia Coli ◽

Health Risk ◽

Shiga Toxin ◽

Salmonella Spp ◽

Public Health Risk ◽

E Coli

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Low Prevalence of Salmonella and Shiga Toxin–Producing Escherichia coli in Lymph Nodes of Australian Beef Cattle

Journal of Food Protection ◽

10.4315/0362-028x.jfp-17-180 ◽

2017 ◽

Vol 80 (12) ◽

pp. 2105-2111 ◽

Cited By ~ 3

Author(s):

Gavin Bailey ◽

Long Huynh ◽

Lachlan Govenlock ◽

David Jordan ◽

Ian Jenson

Keyword(s):

Escherichia Coli ◽

Lymph Nodes ◽

Shiga Toxin ◽

Limit Of Detection ◽

Ground Beef ◽

Plate Count ◽

Salmonella Spp ◽

Live Animal ◽

E Coli ◽

Low Prevalence

ABSTRACT Salmonella contamination of ground beef has been viewed as originating from the surface of carcasses. Recent studies have identified lymph nodes as a potential source of Salmonella contamination because these tissues play an active role in containment of pathogens in the live animal and because some lymph nodes are unavoidably present in manufacturing beef trimmings or primal cuts that may be incorporated into ground beef. A survey was conducted of the microbiological status of lymph nodes from Australian cattle at the time of slaughter to determine the prevalence of microbiological contamination. Sets of lymph nodes (n = 197), consisting of the superficial cervical (prescapular), prepectoral, axillary, presternal, popliteal, ischiatic, subiliac (precrural), coxalis, and iliofemoralis (deep inguinal), were collected from five geographically separated Australian abattoirs over a period of 14 months. Samples were tested for the presence of Salmonella spp. and Shiga toxin–producing Escherichia coli by BAX PCR assay. Aerobic plate count, E. coli, and coliforms were enumerated with a lower limit of detection of 80 CFU per node. The observed prevalence of Salmonella within peripheral lymph nodes was 0.48% (7 of 1,464). Two of the seven lymph nodes in which Salmonella organisms were detected came from the same animal. Grass-fed, grain-fed, and cull dairy cattle were all found to have detectable Salmonella in lymph nodes. All Salmonella detections occurred during cooler months of the year. No Shiga toxin–producing E. coli were detected. Aerobic microorganisms were detected above the limit of quantification in 3.2% of nodes (median count 2.24 log per node), and E. coli was detected in 0.8% of nodes (median count 3.05 log per node). The low prevalence of Salmonella and low concentration of aerobic microorganisms in Salmonella-positive lymph nodes of Australian cattle at the time of slaughter suggest that the likelihood of lymph nodes contributing significantly to the presence of Salmonella in ground beef is low.

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Informing source attribution of enteric disease: An analysis of public health inspectors’ opinions on the “most likely source of infection”

Environmental Health Review ◽

10.5864/d2011-003 ◽

2012 ◽

Vol 55 (01) ◽

pp. 27-36 ◽

Cited By ~ 6

Author(s):

Danielle Dumoulin ◽

Andrea Nesbitt ◽

Barbara Marshall ◽

Nancy Sittler ◽

Frank Pollari

Keyword(s):

Public Health ◽

Escherichia Coli ◽

Food Safety ◽

Disease Risk ◽

Parasitic Disease ◽

Enteric Disease ◽

Source Attribution ◽

Effective Prevention ◽

Safety Practices ◽

Source Of Infection

Enteric illness continues to place a significant burden on the health of Canadians. To reduce this burden and establish effective prevention and intervention practices, the sources of these infections need to be understood. Multiple methods have been used to examine source attribution. This study presents a unique method for examining source attribution and enteric disease risk factors within a Canadian community. Open text data from 2006 to 2010 were analyzed on the “most likely source of infection” (MLSI) identified by public health inspectors (PHIs), investigating sporadic endemic cases of enteric illness in the Region of Waterloo, Ontario. The MLSI data were classified under nine categories and analyzed using five disease groups consisting of overall enteric disease, campylobacteriosis, salmonellosis, verotoxigenic Escherichia coli (VTEC) infection, and parasitic disease. Food was the most frequently reported MLSI for overall enteric disease (26.1%), salmonellosis (41.1%), and VTEC infection (31.3%). Animal and water exposure were the most frequently reported MLSI for campylobacteriosis (26.2%) and parasitic disease (45.8%), respectively. Food safety practices were more frequently implicated as the source of infection for salmonellosis (17.7%) and campylobacteriosis (12.6%), compared with verotoxigenic Escherichia coli (VTEC) infection (6.3%) and parasitic disease (1.0%). The category unpasteurized was the third most frequent MLSI for campylobacteriosis (12.6%), along with food safety practices (12.6%). The analysis of PHIs’ opinions on the MLSI of enteric disease is a valuable method to inform source attribution. The enhanced Canada's National Integrated Enteric Pathogen Surveillance Program (C-EnterNet) standardized questionnaires provided an important source of data to complete this analysis. The results from this study can be used to generate hypotheses for future studies and inform public health policy and practice at the local, provincial, and national levels to reduce the burden of enteric illness in Canada.

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Genotypic Analyses of Escherichia coli O157:H7 and O157 Nonmotile Isolates Recovered from Beef Cattle and Carcasses at Processing Plants in the Midwestern States of the United States

Applied and Environmental Microbiology ◽

10.1128/aem.67.9.3810-3818.2001 ◽

2001 ◽

Vol 67 (9) ◽

pp. 3810-3818 ◽

Cited By ~ 80

Author(s):

Genevieve A. Barkocy-Gallagher ◽

Terrance M. Arthur ◽

Gregory R. Siragusa ◽

James E. Keen ◽

Robert O. Elder ◽

...

Keyword(s):

Escherichia Coli ◽

The United States ◽

Escherichia Coli O157 ◽

Genomic Fingerprinting ◽

E Coli ◽

Beef Processing ◽

Processing Plants ◽

Shiga Toxin Genes ◽

Carcass Contamination ◽

Animal Isolates

ABSTRACT Escherichia coli O157:H7 and O157 nonmotile isolates (E. coli O157) previously were recovered from feces, hides, and carcasses at four large Midwestern beef processing plants (R. O. Elder, J. E. Keen, G. R. Siragusa, G. A. Barkocy-Gallagher, M. Koohmaraie, and W. W. Laegreid, Proc. Natl. Acad. Sci. USA 97:2999–3003, 2000). The study implied relationships between cattle infection and carcass contamination within single-source lots as well as between preevisceration and postprocessing carcass contamination, based on prevalence. These relationships now have been verified based on identification of isolates by genomic fingerprinting.E. coli O157 isolates from all positive samples were analyzed by pulsed-field gel electrophoresis of genomic DNA after digestion with XbaI. Seventy-seven individual subtypes (fingerprint patterns) grouping into 47 types were discerned among 343 isolates. Comparison of the fingerprint patterns revealed three clusters of isolates, two of which were closely related to each other. Remarkably, isolates carrying both Shiga toxin genes and nonmotile isolates largely fell into specific clusters. Within lots analyzed, 68.2% of the postharvest (carcass) isolates matched preharvest (animal) isolates. For individual carcasses, 65.3 and 66.7% of the isolates recovered postevisceration and in the cooler, respectively, matched those recovered preevisceration. Multiple isolates were analyzed from some carcass samples and were found to include strains with different genotypes. This study suggests that mostE. coli O157 carcass contamination originates from animals within the same lot and not from cross-contamination between lots. In addition, the data demonstrate that most carcass contamination occurs very early during processing.

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