scholarly journals PCR Based Detection of Shiga Toxin Producing E. coli in Commercial Poultry and Related Environments

Author(s):  
Homaira Anzum Himi ◽  
Md. Shafiullah Parvej ◽  
M. Bahanur Rahman ◽  
K M Nasiruddin ◽  
Wahedul Karim Ansari ◽  
...  

Shiga toxin (Stx)-producing E. coli (STEC) is the most important foodborne pathogen which is the causal agent of mild diarrhea, bloody diarrhea, hemolytic-uremic syndrome (HUS) in human. The present study was designed to determine the prevalence and identification of Shiga toxin (Stx)-producing E. coli in poultry, detection of its source of infection in poultry and transmission pattern to human. For this purpose a total of 150 samples (cloacal swab-60, feed -15, water-15 and egg -60) were collected and analyzed in bacteriology laboratory by cultured in different bacteriological media followed by gram’s staining, biochemical tests and Polymerase Chain reaction (PCR). The PCR was performed by targeting 16s rRNA gene and shiga toxin producing gene in E. coli. Out of 150 collected samples, E. coli was found in 81 (54%) samples. Presence of E. coli was 100% in both feed (n=15) and egg (n=60), whereas 10% in cloacal swab (n=6). Water samples were totally free of E. coli. The stx2 gene was detected in all samples whether all samples were negative for stx1 gene. The study revealed that, poultry feed acts as a source of E. coli infection in poultry, which may be transmitted to environment and human via meat or eggs. Antibiotic sensitivity test revealed that isolated bacteria were highly sensitive to Ciprofloxacin.

2021 ◽  
Vol 14 (2) ◽  
pp. 78-90
Author(s):  
Ahmed Jarad ◽  
Kh. Al- Jeboori

The present study focus on non-O157 Shiga toxin-producing E. Coli (STEC), included a bacteriological study was subjected to provide additional information for non-O157 STEC prevalence in children and calves. Isolation by using selective culturing media (CHROMagar STEC and CHROMagar O157) from 127 children suffering from diarrhea and 133 calves in Al- Muthanna province. Characterization depends on culturing positive colony on MacConkey agar and Levin’s Eosin Methylene blue agar, staining single colony from the growth by gram stain, biochemical tests; Indole, the Methyl Red, Voges-Proskauer, Citrate test, Oxidase, Catalase, Urease, Motility, Kligler Iron and Api-20E, were done to confirm a diagnosis of non-O157 STEC, The reliable isolation as non-O157 STEC serotyping by specific latex agglutination test for the target non-O157 STEC (big six) serogroup (O26, O45, O103, O111, O121 and O145). The current study showed the prevalence of non-O157 STEC was 20 of out 127 (15.73%) in samples collected from children and 27 / 133 (20.30%) in calves samples in conclusion the Non-O157 STEC is an important cause of diarrhea in children, and calves; finally, the calves play an important reservoir for Non-O157 STEC.


2019 ◽  
Vol 7 (3) ◽  
pp. 91 ◽  
Author(s):  
Sunniva Hoel ◽  
Olav Vadstein ◽  
Anita Jakobsen

Minimally processed and ready-to-eat (RTE) seafood products are gaining popularity because of their availability in retail stores and the consumers’ perception of convenience. Products that are subjected to mild processing and products that do not require additional heating prior to consumption are eaten by an increasing proportion of the population, including people that are more susceptible to foodborne disease. Worldwide, seafood is an important source of foodborne outbreaks, but the exact burden is not known. The increased interest in seafood products for raw consumption introduces new food safety issues that must be addressed by all actors in the food chain. Bacteria belonging to genus Aeromonas are ubiquitous in marine environments, and Aeromonas spp. has held the title “emerging foodborne pathogen” for more than a decade. Given its high prevalence in seafood and in vegetables included in many RTE seafood meals, the significance of Aeromonas as a potential foodborne pathogen and a food spoilage organism increases. Some Aeromonas spp. can grow relatively uninhibited in food during refrigeration under a broad range of pH and NaCl concentrations, and in various packaging atmospheres. Strains of several Aeromonas species have shown spoilage potential by the production of spoilage associated metabolites in various seafood products, but the knowledge on spoilage in cold water fish species is scarce. The question about the significance of Aeromonas spp. in RTE seafood products is challenged by the limited knowledge on how to identify the truly virulent strains. The limited information on clinically relevant strains is partly due to few registered outbreaks, and to the disputed role as a true foodborne pathogen. However, it is likely that illness caused by Aeromonas might go on undetected due to unreported cases and a lack of adequate identification schemes. A rather confusing taxonomy and inadequate biochemical tests for species identification has led to a biased focus towards some Aeromonas species. Over the last ten years, several housekeeping genes has replaced the 16S rRNA gene as suitable genetic markers for phylogenetic analysis. The result is a more clear and robust taxonomy and updated knowledge on the currently circulating environmental strains. Nevertheless, more knowledge on which factors that contribute to virulence and how to control the potential pathogenic strains of Aeromonas in perishable RTE seafood products are needed.


2013 ◽  
Vol 142 (5) ◽  
pp. 1029-1033 ◽  
Author(s):  
S. SÁNCHEZ ◽  
M. GARCÍA CENOZ ◽  
C. MARTÍN ◽  
X. BERISTAIN ◽  
M. T. LLORENTE ◽  
...  

SUMMARYA Spanish household was identified through a Public Health follow up on a Shiga toxin-producingEscherichia coli(STEC)-positive 14-month-old girl reporting bloody diarrhoea, with the four household members experiencing either symptomatic or asymptomatic STEC and/or atypical enteropathogenicE. coli(aEPEC) shedding. In total, two different O76:H19 STEC strains and six aEPEC strains belonging to multiple serotypes were isolated and characterized in the household during a 5-month period. Prolonged asymptomatic shedding of O76:H19 STEC and O51:H49 aEPEC was detected in two family members. Although there was no conclusive evidence, consumption of vegetables fertilized with sheep manure was the suspected source of infection. This study highlights the risk of cross-infections posed by prolonged asymptomatic carriage and close household contact between family members, and illustrates the importance of molecular epidemiology in understanding disease clusters.


2017 ◽  
Vol 14 (2) ◽  
pp. 289-295
Author(s):  
M. M. Islam ◽  
S. Ahamed ◽  
M. Y. Arafat ◽  
I. Hasan ◽  
M. Rahman ◽  
...  

This study was designed to determine the shiga toxin producing genes and to investigate antibiotic sensitivity or resistant patterns of the Escherichia coli isolated from diarrheic children at Mymensingh Medical College Hospital, Bangladesh. A total of 83 stool samples were collected and screened for the detection of E. coli on the basis of cultural, staining and biochemical properties followed by molecular detection by Polymerase Chain Reaction (PCR) using genus specific 16SrRNA primers. Antimicrobial susceptibility pattern of E. coli was determined by disc diffusion method against 9 antimicrobial agents. In this study, 27 (32.53%) out of 83 samples, were confirmed as E. coli. Overall prevalence of shiga toxin producing E. coli (STEC) among the examined children was 1.20% (n=1/83).  Further, 27 E. coli isolates were analyzed for the presence of Stx-1 and Stx-2 genes by duplex-PCR.  The STEC isolate was confirmed to be positive for the presence of the Stx-2 gene only. Highest susceptibility of the E. coli isolates was found against Gentamicin (92.59%), followed by Ciprofloxacin (48.14%) and Moxifloxacin (33.33%). More than 77.78% of the isolates were resistant to more than three antibiotics thus defined as multi-drug resistant (MDR). In conclusion, Gentamicin and Ciprofloxacin can be recommended as the effective drugs successful treatment of STEC infections in children.


2018 ◽  
Vol 9 (2) ◽  
pp. 275-780 ◽  
Author(s):  
O. М. Berhilevych ◽  
V. V. Kasianchuk ◽  
O. M. Deriabin ◽  
M. D. Kukhtyn

Escherichia coli is part of the normal microflora of the intestinal tract of humans and warm-blooded animals, but its presence in raw material and food of animal origin is considered as fecal contamination and can be very dangerous for consumers. The determination of the number of E. coli in raw material and food is important because among them can be pathogenic strains. The most dangerous strains are considered enterohemorrhagic E. coli as a causative agent of severe bloody diarrhea and hemorrhagic uremic syndrome in humans through the production of Shiga-toxin, which is the main virulence factor, responsible for disease. The aim of this study was to identify the prevalence of Shiga toxin-producing strains of E. coli (STEC) from swabs of beef and swine carcass in slaughterhouses in Ukraine and characterize their genes, which are responsible for pathogenic properties. A total of 230 samples of swabs from beef (130) and swine (100) carcasses were obtained from 5 slaughterhouses in Ukraine between 2012 and 2015. Samples of swabs from carcasses were randomly selected at the final point of the process after the final washing of the carcass from the following areas: distal hind limb, abdomen (lateral and medial) from swine carcasses, brisket, flank and flank groin areas from beef carcasses. All samples were examined by culture-dependent method, after that each positive isolate of STEC was analyzed by multiplex PCR to detect the stx1, stx2, and eae genes. Out of 230 collected samples, seven (7.2%) were contaminated with STEC. The highest prevalence of STEC was found in swabs from beef carcasses (8.1%) in comparison to swabs from swine carcasses (5.7%). The stx1 gene was the predominant gene detected in all STEC positive samples. The eae gene was found in one of the examined isolates from beef carcass. Three isolates from swabs of beef carcass carried both stx1 and stx2 genes, one isolate showed association between stx1 and eae genes, one isolate was positive for stx1 gene only. In swabs from swine carcasses (2 isolates) stx1 and stx2 genes were presented simultaneously. The results of this study suggested that fresh raw meat could be a potential vehicle for transmission of the Shiga toxin-producing strain of E. coli to humans. This is the first report of STEC prevalence in beef and swine carcasses in Ukraine and these data will be valuable for microbiological risk assessment and help the appropriate services to develop strategies to mitigate health risk.


2019 ◽  
Author(s):  
Solomon Abreham ◽  
Akafete Teklu ◽  
Eric Cox ◽  
Tesfaye Sisay Tessema

Abstract Background : Cattle have been identified as a major reservoir of E. coli O157:H7 for human infection; the ecology of the organism in sheep and goats is less understood. This study was carried out to determine prevalence, source of infection, antibiotic resistance and molecular characterization of Escherichia coli O157: H7 isolated from sheep and goat. Methods : Systematic random sampling was carried out at Modjo export abattoir, Ethiopia, from November 2012 to April 2013 to collect 408 samples from 72 sheep and 32 goats. Samples collected were skin swabs, fecal samples, intestinal mucosal swabs and the inside and outside part of carcasses as well as carcass in contacts such as workers hands, knife, hook and carcass washing water. Then, samples were processed following standard bacteriological procedures. Non-Sorbitol fermenting colonies were tested on latex agglutination test and the positives are subjected to PCR for detection of attaching and effacing genes ( eaeA) and shiga toxin producing genes ( stx1 and stx2 ). All E. coli O157:H7 isolates were checked for their susceptibility pattern towards 15 selected antibiotics. Results : E. coli O157:H7 were detected in only 20/408 samples (4.9%). Among these 20 positive samples, 70% (14/20), 25% (5/20) and 5% (1/20) were from sheep, goats and knife samples, respectively. No significant associations were found between carcasses and the assumed sources of contaminations. Of all the 20 isolates virulence genes were found in 10 (50%) of them; 3 (15%) with only the eaeA gene and 7(35%) expressing eaeA and stx2 genes. All the isolates were susceptible to Norfloxacin (NOR) (100%). Conclusions : The presence of virulence genes shows E. coli O157:H7 is a potential source of human infection in Ethiopia. Key words : Abattoir, antibiotic sensitivity, CT-SMAC, E. coli O157:H7, IMS, Latex agglutination, multiplex PCR.


2020 ◽  
pp. JCM.02624-20
Author(s):  
Nguyen Thi Thu Huong ◽  
Atsushi Iguchi ◽  
Ritsuko Ohata ◽  
Hisahiro Kawai ◽  
Tadasuke Ooka ◽  
...  

Shiga toxin-producing Escherichia coli (STEC) is an important foodborne pathogen. Although most cases of STEC infection in humans are due to O157 and non-O157 serogroups, there are also reports of infection with STEC strains that cannot be serologically classified into any O-serogroup (O-serogroup untypeable, OUT). Recently, it has become clear that even OUT strains can be subclassified based on the diversity of O-antigen biosynthesis gene cluster (O-AGC) sequences. Cattle are thought to be a major reservoir of STEC strains belonging to various serotypes; however, the internal composition of OUT STEC strains in cattle remains unknown. In this study, we screened 366 STEC strains isolated from healthy cattle by using multiplex PCR kits including primers that targeted novel O-AGC types (Og-types) found in OUT E. coli and Shigella strains in previous studies. Interestingly, 94 (25.7%) of these strains could be classified into 13 novel Og-types. Genomic analysis revealed that the results of the in silico serotyping of novel Og-type strains were perfectly consistent with those of the PCR experiment. In addition, it was revealed that a dual Og8+OgSB17-type strain carried two types of O-AGCs from E. coli O8 and Shigella boydii type 17 tandemly inserted at the locus, with both antigens expressed on the cell surface. The results of this comprehensive analysis of cattle-derived STEC strains may help improve our understanding of the strains circulating in the environment. Additionally, the DNA-based serotyping systems used in this study could be used in future epidemiological studies and risk assessments of other STEC strains.


Mobile phone is a device that keeps in contact with our sensitive body parts including faces, hands, nose, ears, and lips, etc. most of the time. Although we know many bad aspects of mobile phones; we are indifferent to its bacterial contamination. Smartphone screen is an endless reservoir of pathogenic bacteria and works as an object in spreading those bacteria. The purpose of the study was to identify pathogenic bacteria from smartphone screen and finding some common causes of bacterial contamination. So, a public survey was conducted among 100 students from the Dept. of Genetic Engineering & Biotechnology, University of Rajshahi to know the uses pattern of their particular smartphone. Then, for the lab-based work samples were collected from the smartphone screen of the students by sterile swabs moistened with normal saline water. Among the samples, four strains were selected based on bacterial concentration for further analysis. Out of four, two strains were gram-positive and two were gram-negative. Biochemical tests indicated that all of them were pathogenic and the selected gram-positive bacteria were coagulase-positive Staphylococcus species and coagulase-negative Staphylococcus species.16S-rRNA gene sequencing identified the selected two-gram negative strains as Stenotrophomonas maltophilia and Klebsiella pneumoniae. The antibiotic sensitivity test referred that all the bacteria were multidrug-resistant and may be dangerous for compromised immune patients.


2017 ◽  
Vol 4 (1) ◽  
pp. 9
Author(s):  
Nancy Carlos ◽  
Eduardo Tafur ◽  
Elizabeth Solano ◽  
Paloma Alcazar

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.


Author(s):  
E. C. Okechukwu ◽  
E. U. Amuta ◽  
G. M. Gberikon ◽  
N. Chima ◽  
B. Yakubu ◽  
...  

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.


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