scholarly journals Shiga toxin-producing Escherichia coli (STEC) and Salmonella spp. in lettuce

2020 ◽  
Vol 9 (7) ◽  
pp. e281974150
Author(s):  
Bruna Ribeiro Arrais ◽  
Marcos Roberto Alves Ferreira ◽  
Talícia Santos Silva ◽  
Jefferson Fernando Naves Pinto ◽  
Ariel Eurides Stella ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Virulence Genes ◽  
Foodborne Illnesses ◽  
Biochemical Tests ◽  
Salmonella Spp ◽  
E Coli ◽  
Crop Type ◽  
Fresh Vegetables ◽  
The City

Foodborne illnesses are relevant to public health, especially in contaminated foods that are eaten without prior cooking, such as lettuce. The objective was to evaluate the contamination by Shiga toxin-producing Escherichia coli (STEC), E. coli and Salmonella spp. in lettuce in commercial food-establishments in the city of Jataí, Goiás, Brazil. The variables were: type of crop, type of establishment and coliform count. The DNA of E. coli isolates were analyzed by PCR to the research of virulence genes. Isolates compatible with Salmonella in the biochemical tests were submitted for serology with Salmonella antisera. Thirty samples of lettuce were evaluated, eleven samples were positive for E. coli, (36.67%), and one sample (3.33%) tested positive for STEC hydroponic crop. The two STEC isolates were positive for the stx2 gene. Conventionally grown products were 2.4 times more likely to be contaminated with E. coli. The presence of Salmonella spp. was confirmed in 16.67% (5/30) of the samples. The presence of potentially pathogenic microorganisms in the analyzed samples indicates the need for special care to be taken in preparing fresh vegetables before they are consumed in natura, like avoid excessive handling, and washing with sanitizers.

scholarly journals EVOLUÇÃO DA QUALIDADE MICROBIOLÓGICA DE QUEIJO MINAS FRESCAL COMERCIALIZADO EM CURITIBA (PR) NO INTERVALO DE 10 ANOS (1999 E 2009) Assessment of the microbiological quality of Minas frescal cheese commercialized in the city of Curitiba, Parana State, Brazil at 10 years’ interval (1999 and 2009)

2012 ◽  
Vol 10 (3) ◽  
pp. 243 ◽  
Author(s):  
Hanna Lethycia Wolupeck ◽  
Helen Caroline Raksa ◽  
Luciane Silvia Rossa ◽  
Raquel Biasi ◽  
Renata Ernlund Freitas de Macedo
Keyword(s):  
Escherichia Coli ◽  
Microbiological Quality ◽  
Salmonella Spp ◽  
E Coli ◽  
The City

O queijo Minas frescal é um dos mais populares do Brasil, porém o alto teor de umidade associado ao métodode processamento, muitas vezes artesanal, e de armazenamento desse produto o tornam muito perecível.Este trabalho teve como objetivo avaliar e comparar a qualidade microbiológica de queijo Minas frescalcomercializado na cidade de Curitiba (PR) nos anos de 1999 e 2009, verificando a evolução na qualidadehigiênico-sanitária desse produto no período de 10 anos. Foram analisadas 11 marcas comerciais de queijo Minas frescal disponíveis no comércio varejista da cidade de Curitiba, sendo amostradas cinco unidades de cada marca, totalizando 55 amostras. Os queijos foram submetidos à pesquisa de Salmonella spp., contagem de coliformes totais e Escherichia coli, contagem de Staphylococcus coagulase positiva e contagem de aeróbios mesófilos, com resultados expressos em UFC/g. Das 55 amostras de queijo, 41,82% e 78,18% apresentaram contagem de E. coli e de coliformes totais acima do limite permitido, respectivamente. Somente uma amostra (1,82%) do total avaliado mostrou-se em desacordo com os padrões para S. coagulase positiva e uma para Salmonella spp. Ambas as amostras foram adquiridas em 2009. Todas as amostras avaliadas em 2009 apresentaram elevada contagem de aeróbios mesófilos, revelando alta carga microbiana. Comparativamente, os queijos avaliados em 1999 mostraram qualidade microbiológica superior aos queijos avaliados em 2009 (p < 0,05). Destes, 100% apresentaram no mínimo um parâmetro microbiológico em desacordo com a legislação vigente, indicando que a qualidade dos queijos Minas frescal avaliados em 2009 apresentou-se inferior a dos queijos avaliados em 1999.

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

2016 ◽  
Vol 237 ◽  
pp. 10-16 ◽  
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

Prevalence of shiga toxin-producing Escherichia coli O157, O26 and O111 in milk, meat and faeces of cattle, sheep and pigs slaughtered in Benin

2020 ◽  
Vol 152 ◽  
pp. 15667-15675
Author(s):  
Chakirath Folakè Arikè Salifou ◽  
Cyrille Boko ◽  
Isidore Houaga ◽  
Raoul Agossa ◽  
Isabelle Ogbankotan ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Virulence Genes ◽  
Animal Origin ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Milk Samples ◽  
Food Of Animal Origin ◽  
Cattle Faeces ◽  
Risk Assessment And Management

Objectives: The study aimed to search for E. coli O157 and non-O157 in milk, meat and faeces of cattle, sheep and pigs slaughtered in Cotonou. Methodology and Results: One hundred and Seventy-Five (175) samples including 25 meat, 25 faeces per species and 25 milk from cattle were analysed for E. coli O157; O26 and O111 and the virulence genes were identified by PCR. The SAS software (1998) and the bilateral Z test were used to calculate and compare the identification frequencies. E. coli O157 was identified in 4% of cattle faeces, 4% of sheep faeces, and 20% of beef and, in 20% of milk samples. E. coli O26 was identified in 12% of cattle faeces and, in 8% of beef samples. E. coli O111 was identified at frequencies of 8%, and 12% in faeces of sheep and pigs, respectively. The eae gene was detected in 4% of beef, ovine meat, milk, pig faeces and in sheep faeces. stx1 was detected in 8% of milk, and in 4% of bovine and sheep faeces. The strains possessing the gene were all of E. coli O157 with the exception of one from pig faeces identified as O111. Conclusions and application of findings: The presence of these serogroups of E. coli with virulence genes poses a real food safety problem in Benin. This study findings must be taken into account for risk assessment and management related to the consumption of food of animal origin. Keywords: Benin, E. coli O157, O26, O111, faeces, meat, milk

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

2017 ◽  
Vol 80 (12) ◽  
pp. 2105-2111 ◽  
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.

Isolation and Characterization of Shiga Toxin–Producing Escherichia coli Serogroups O26, O45, O103, O111, O113, O121, O145, and O157 Shed from Range and Feedlot Cattle from Postweaning to Slaughter

2014 ◽  
Vol 77 (7) ◽  
pp. 1052-1061 ◽  
Author(s):  
ABEL B. EKIRI ◽  
DOUGLAS LANDBLOM ◽  
DAWN DOETKOTT ◽  
SUSAN OLET ◽  
WEILIN L. SHELVER ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Virulence Genes ◽  
Beef Cows ◽  
Laboratory Culture ◽  
Feedlot Cattle ◽  
Fecal Shedding ◽  
E Coli ◽  
Isolation And Characterization ◽  
Inspection Service

Cattle are the main reservoirs for Shiga toxin–producing Escherichia coli (STEC) strains. E. coli O26, O45, O103, O111, O121, O145, and O157 are among the STEC serogroups that cause severe foodborne illness and have been declared as adulterants by the U.S. Department of Agriculture, Food Safety and Inspection Service. The objectives of this study were (i) to estimate the prevalence of non-O157 STEC and E. coli O157 in naturally infected beef cows and in steer calves at postweaning, during finishing, and at slaughter and (ii) to test non-O157 STEC isolates for the presence of virulence genes stx1, stx2, eaeA, and ehlyA. Samples were collected from study animals during multiple sampling periods and included fecal grabs, rectal swabs, and midline sponge samples. Laboratory culture, PCR, and multiplex PCR were performed to recover and identify E. coli and the virulence genes. The prevalence of non-O157 STEC (serogroups O26, O45, O103, O111, O121, O113, and O145) fecal shedding ranged from 8% (4 of 48 samples) to 39% (15 of 38 samples) in cows and 2% (1 of 47 samples) to 38% (9 of 24 samples) in steer calves. The prevalence of E. coli O157 fecal shedding ranged from 0% (0 of 38 samples) to 52% (25 of 48 samples) in cows and 2% (1 of 47 samples) to 31% (15 of 48 samples) in steer calves. In steer calves, the prevalence of non-O157 STEC and E. coli O157 was highest at postweaning, at 16% (15 of 96 samples) and 23% (22 of 96 samples), respectively. Among the 208 non-O157 STEC isolates, 79% (164 isolates) had stx1, 79% (165 isolates) had stx2, and 58% (121 isolates) had both stx1 and stx2 genes. The percentage of non-O157 STEC isolates encoding the eaeA gene was low; of the 165 isolates tested, 8 (5%) were positive for eaeA and 135 (82%) were positive for ehlyA. Findings from this study provide further evidence of non-O157 STEC shedding in beef cows and steer calves particularly at the stage of postweaning and before entry into the feedlot.

scholarly journals Detection of Enterobacteriaceae, antimicrobial susceptibility, and virulence genes of Escherichia coli in canaries (Serinus canaria) in northeastern Brazil

2019 ◽  
Vol 39 (3) ◽  
pp. 201-208
Author(s):  
Antonio Jackson F. Beleza ◽  
William C. Maciel ◽  
Arianne S. Carreira ◽  
Windleyanne G.A. Bezerra ◽  
Cecilia C. Carmo ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Susceptibility ◽  
Virulence Genes ◽  
Morphological Characteristics ◽  
Brain Heart Infusion ◽  
Enterobacter Aerogenes ◽  
Northeastern Brazil ◽  
Salmonella Spp ◽  
Pcr Screening ◽  
E Coli

ABSTRACT: This study aimed to verify the presence of members from the Enterobacteriaceae family and determine antimicrobial susceptibility profiles of the isolates in canaries bred in northeastern Brazil; in addition, the presence of diarrheagenic Escherichia coli (DEC) and avian pathogenic Escherichia coli (APEC) was also verified in these birds. Samples were collected during an exhibition organized by the Brazilian Ornithological Federation in July 2015 in Fortaleza, Brazil. A total of 88 fecal samples were collected and submitted to pre-enrichment step using buffered peptone water, followed by enrichment with the following broths: brain-heart infusion, Rappaport-Vassiliadis, and Selenite-Cystine. Subsequently, aliquots were streaked on MacConkey, brilliant green and salmonella-shigella agar plates. Colonies were selected according to morphological characteristics and submitted to biochemical identification and antimicrobial susceptibility tests with disk-diffusion technique. E. coli strains were evaluated for the presence of eight DEC genes and five APEC genes through conventional polymerase chain reaction (PCR) screening. The most frequent species observed were Pantoea agglomerans (25%), Serratia liquefaciens (12.5%), and Enterobacter aerogenes (9.1%). A single rough strain of Salmonella enterica subsp. enterica was identified in one sample (1.1%). High resistance rates to amoxicillin (78.7%) and ampicillin (75.4%) were identified. Polymyxin B (9.8%), gentamycin (6.6%), and enrofloxacin (6.6%) were the most efficient antibiotics. The total number of multidrug-resistant strains (isolates resistant to more than three antimicrobial classes) was 23 (37.7%). Four E. coli strains were tested for the virulence genes, and two were positive for APEC virulence genes: one strain was positive for iutA and the other for hlyF. In conclusion, canaries in northeastern Brazil participating in exhibitions may present Salmonella spp., Escherichia coli and other enterobacteria in the intestinal microbiota with antimicrobial resistance. These results indicate that, although the E. coli strains recovered from canaries in this study have some virulence genes, they still do not fulfill all the requirements to be considered APEC.

scholarly journals Prevalence and antibiotic resistance profile of Shiga toxin-producing Escherichia coli isolated from diarrheal samples

2020 ◽  
Author(s):  
Farzad Esavand Heydari ◽  
Mojtaba Bonyadian ◽  
Hamdallah Moshtaghi ◽  
Masoud Sami
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Shiga Toxin ◽  
Virulence Genes ◽  
Enterohemorrhagic Escherichia Coli ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Resistance Profile ◽  
E Coli ◽  
Antibiotic Resistance Profile

Background and Objectives: Enterohemorrhagic Escherichia coli (EHEC) causes bloody and non-bloody diarrhea, intestinal infection and extraintestinal complications in humans. This study aimed to isolate and evaluate the prevalence of E. coli O157: H7 and other Shiga toxin-producing E. coli (STEC) and identify the virulence genes (stx1, stx2, hly and eaeA) from patients with diarrhea. Also, the antibiotic resistance profile of the isolated strains was evaluated. Materials and Methods: A total of 100 stool samples were collected from patients with acute diarrhea referring to the hospital and clinics in Isfahan County, Iran. Phenotypic tests and PCR assay were used for detection of E. coli O157: H7 and other Shiga toxin-producing E. coli. The presence of virulence genes (stx1, stx2, hly and eaeA) were identified by PCR. The antibiotic resistance profile of the isolates was determined using the agar disk diffusion method. The results were analyzed descriptively by Sigma stat version 4 software. Results: Seventy - eight out of 100 samples (78%) were contaminated with E. coli. E. coli O157 was isolated from five samples (6.4%), of which only two strains (2.56%) were identified as E. coli O157: H7. According to the results, out of two E. coli O157: H7 isolates, one (50%) isolate contained eaeA and two isolates (100%) contained Stx1, Stx2, hlyA genes. Out of three (3.84%) E. coli O157: HN, one of the isolate (33.3%) contained stx1 and, two isolates (66.7%) were positive for hlyA genes. Also, the results revealed that six strains (7.69%) were non-O157: H7 STEC, of which two isolates (33.3%) contained stx1 and four isolates (66.7%) were positive for stx2 and hlyA genes. The results of antibiogram tests revealed that all of the STEC isolates (100%) were sensitive to imipenem followed by kanamycin, gentamicin and nitrofurantoin (91%). High resistance (54.5%) to ampicillin and ciprofloxacin was observed among the STEC isolates. Conclusion: The results of the current study showed that although the prevalence of E. coli O157: H7 was low among patients with diarrhea, the other STEC strains with relative resistance to antibiotics are more prevalent.

scholarly journals Enterobacterias de la paloma de castilla Columba livia en la ciudad de Lima, Perú

2017 ◽  
Vol 4 (1) ◽  
pp. 9
Author(s):  
Nancy Carlos ◽  
Eduardo Tafur ◽  
Elizabeth Solano ◽  
Paloma Alcazar
Keyword(s):  
Enterobacter Aerogenes ◽  
Columba Livia ◽  
Cloacal Swab ◽  
Biochemical Tests ◽  
Salmonella Spp ◽  
E Coli ◽  
Private Laboratory ◽  
Salmonella Pullorum ◽  
Zoonotic Bacteria ◽  
The City

The rock dove Columba livia is an exotic and feral bird that has been described as carrying various agents potentially pathogenic to man and other birds, including bacteria such as Salmonella spp. and E. coli, however, there are few studies regarding infectious disease agents carried by the species in our country. The objective of the study was to determine the enterobacterias present in this free-living bird resident in the City of Lima. During the months of June and July of 2014, 27 adult individuals of C. livia were captured in two zoos located in the districts of Chorrillos and San Juan de Miraflores. A cloacal swab was made to each bird and transported in the Cary Blair transport medium at 4 °C to a private laboratory. In the laboratory, samples were plated on McConkey agar and SS agar, and then proceeded to the identification using biochemical tests (TSI, LIA, Indol, SIM, Citrate, Methyl Red and Voges Proskauer). A total of 35 bacterial colonies were isolated 85.19 % (23/27) from the samples: 62.96 % (17/27) Escherichia coli, 11.11 % (3/27) Enterobacter aerogenes, 11.11 % (3/27) Klebsiella sp., 11.11 % (3/27) Proteus vulgaris, 7.41 % (2/27) Salmonella pullorum, 14.29 % (14/27) Shiguella sp., 11.11 % (3 / 27) Staphylococcus aureus and 3.70 % (1/27) Staphylococcus sp. Here, we report a high frequency of enterobacteria of interest in public health, evidencing the importance of considering rock dove as a reservoir for zoonotic bacteria.

scholarly journals Molecular Identification of Virulence Genes of Escherichia coli Isolated from Cow Milk and Its Products in Abuja, Nigeria

2020 ◽  
pp. 11-18
Author(s):  
E. C. Okechukwu ◽  
E. U. Amuta ◽  
G. M. Gberikon ◽  
N. Chima ◽  
B. Yakubu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Virulence Genes ◽  
Foodborne Pathogen ◽  
Cow Milk ◽  
E Coli ◽  
Milk Samples ◽  
The Family ◽  
High Prevalence ◽  
Polymerase Chain

Shiga toxin-producing Escherichia coli have been identified as an emerging foodborne pathogen which portends serious risk to human health. Cow milk and its products are potential sources of shiga toxin-producing Escherichia coli. A relatively small number from the family of shiga toxin-producing Escherichia coli are pathogenic. It becomes necessary that Cow milk and milk products are regularly screened for the presence of virulence genes in microbes. The study aimed to genetically determine the presence of virulence genes that are characteristic of Enterohaemorrhagic E. coli in 600 milk samples. The E. coli isolates were recovered from the milk samples (n=35), biochemically examined and genetically screened for virulence genes by multiplex Polymerase Chain Reaction (PCR). The results of the molecular profiling revealed that (stx2) was detected in 17(60.7%), (hlyA) 11(39.3%) and eae genes 8(28.6%) of the E. coli isolates respectively, while (stx1) was not detected. The results indicated a high prevalence of virulent shiga toxin-producing Escherichia coli in the milk samples. Priority attention should be given to this microbe as it will demand stringent steps in the detection given that they are known to be rigorous in identification.

Rapid and Reliable Detection of Shiga Toxin–Producing Escherichia coli by Real-Time Multiplex PCR

2012 ◽  
Vol 75 (4) ◽  
pp. 643-650 ◽  
Author(s):  
KELLY S. ANKLAM ◽  
KAUSHI S. T. KANANKEGE ◽  
TINA K. GONZALES ◽  
CHARLES W. KASPAR ◽  
DÖRTE DÖPFER
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Multiplex Pcr ◽  
Real Time ◽  
Shiga Toxin ◽  
Virulence Genes ◽  
Health Concern ◽  
E Coli ◽  
Reliable Detection ◽  
Pcr Assays

Escherichia coli O26, O45, O103, O111, O121, O145, and O157 are the predominant Shiga toxin–producing E. coli (STEC) serogroups implicated in outbreaks of human foodborne illness worldwide. The increasing prevalence of these pathogens has important public health implications. Beef products have been considered a main source of foodborne human STEC infections. Robust and sensitive methods for the detection and characterization of these pathogens are needed to determine prevalence and incidence of STEC in beef processing facilities and to improve food safety interventions aimed at eliminating STEC from the food supply. This study was conducted to develop Taqman real-time multiplex PCR assays for the screening and rapid detection of the predominant STEC serogroups associated with human illness. Three serogroup-specific assays targeted the O-antigen gene clusters of E. coli O26 (wzy), O103 (wzx), and O145 (wzx) in assay 1, O45 (wzy), O111 (manC), and O121 (wzx) in assay 2, and O157 (rfbE) in assay 3. The uidA gene also was included in the serogroup-specific assays as an E. coli internal amplification control. A fourth assay was developed to target selected virulence genes for Shiga toxin (stx1 and stx2), intimin (eae), and enterohemolysin (ehxA). The specificity of the serogroup and virulence gene assays was assessed by testing 100 and 62 E. coli strains and non–E. coli control strains, respectively. The assays correctly detected the genes in all strains examined, and no cross-reactions were observed, representing 100% specificity. The detection limits of the assays were 103 or 104 CFU/ml for pure cultures and artificially contaminated fecal samples, and after a 6-h enrichment period, the detection limit of the assays was 100 CFU/ml. These results indicate that the four real-time multiplex PCR assays are robust and effective for the rapid and reliable detection of the seven predominant STEC serogroups of major public health concern and the detection of their virulence genes.

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