Journal articles: 'Foodborne diseases (DVA)'

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Draeger, Cainara, Rita Akutsu, Renata Zandonadi, Izabel da Silva, Raquel Botelho, and Wilma Araújo. "Brazilian Foodborne Disease National Survey: Evaluating the Landscape after 11 Years of Implementation to Advance Research, Policy, and Practice in Public Health." Nutrients 11, no. 1 (December 25, 2018): 40. http://dx.doi.org/10.3390/nu11010040.

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The poor control of public and private agencies regarding the quality of foods offered to populations has a significant impact on the occurrence of foodborne diseases. Precise information about foodborne diseases (FBD) can adequately inform policy-makers and help to allocate appropriate resources for the control of food safety. This study aimed to evaluate the Brazilian foodborne disease landscape after 11 years of implementation of the Epidemiological Surveillance System of Foodborne Diseases. The study analyzed secondary data from the National System of Injuries and Notifications (SINAN-NET), available from the Health Department. We evaluated the characteristics of FBD, such as the food involved, the location of ingestion, the total time to the outcome investigation, the microorganism involved and deaths. We also calculated the global incidence, mortality and lethality rates of the country. There were 7630 FBD outbreaks in the National Epidemiological Surveillance System of Foodborne Diseases (VE-DTA). Of the registered reports, a total of 134,046 individuals were sick with FBD; 19,394 were hospitalized, and there were 127 registered deaths. We found a coefficient of incidence of FBD of 67.57 per 100,000 inhabitants; a mortality coefficient of 0.06 per 100,000 inhabitants and lethality of 0.09% over the 11 years investigated. Data are probably underreported since the VE-DTA system lacks completeness, and because FBD symptoms are mostly mild, a large part of the population does not seek care from health services.

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Draeger, Cainara, Rita Akutsu, Wilma Araújo, Izabel da Silva, Raquel Botelho, and Renata Zandonadi. "Epidemiological Surveillance System on Foodborne Diseases in Brazil after 10-Years of Its Implementation: Completeness Evaluation." International Journal of Environmental Research and Public Health 15, no. 10 (October 17, 2018): 2284. http://dx.doi.org/10.3390/ijerph15102284.

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This study aimed to evaluate the data quality of the Brazilian Epidemiological Surveillance System on Foodborne Diseases (VE-DTA) through the evaluation of the completeness of the record after 10-years of its implementation. The study evaluated the measurement of completeness by quantifying ignored, incomplete or blank responses of the data items filled. The evaluation used the percentage of completion of these items regarding the total number of notifications registered in the system. We organized the results according to the general Category of completeness of the database, by year of notification and region of occurrence. We also evaluated the overall completeness percentages of the database and the completeness levels according to the degree of recommendation of completion of each variable (mandatory, essential, and complementary) by the VE-DTA manual. The system presented 7037 outbreaks of foodborne diseases. According to the completeness classification, the database presented general classification as Category 1 since it has 82.1% (n = 5.777) of variables with the level of completion up to 75.1%. We observed that 8.6% of the database was classified as category 2; 9.2% as category 3 and 0.1% as category 4. The improvement on database quality regarding completeness can positively impact on public health and public policies, reducing the number of FBDs deaths.

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Zhang, Xueyan, Imran Mahmood Khan, Hua Ji, Zhouping Wang, Huili Tian, Wenbo Cao, and Weiyu Mi. "A Label-Free Fluorescent Aptasensor for Detection of Staphylococcal Enterotoxin A Based on Aptamer-Functionalized Silver Nanoclusters." Polymers 12, no. 1 (January 7, 2020): 152. http://dx.doi.org/10.3390/polym12010152.

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Staphylococcal enterotoxin A (SEA) is a worldwide public health problem accounting for the majority of food poisoning which is produced by Staphylococcus aureus, threatening human health and leading to various foodborne diseases. Therefore, it is of great significance to develop a sensitive detection method for SEA to ensure food safety and prevent foodborne diseases in humans. In this study, an adaptive fluorescence biosensor for the detection of staphylococcal enterotoxin A (SEA) was designed and developed by combining DNA silver nanoclusters (DNA-AgNCs) with polypyrrole nanoparticles (PPyNPs). Fluorescent AgNCs, synthesized using aptamers as templates, were used as fluorescence probes, whose fluorescence was quenched by PPyNPs. In the presence of the target SEA, DNA-AgNCs were forced to desorb from the surface of PPyNPs through the binding of SEA with the aptamer-DNA-AgNCs, thereby resulting in fluorescence recovery. Under the optimized conditions, the relative fluorescence intensity (FI) showed a linear relationship with the SEA concentration in the range from 0.5 to 1000 ng/mL (Y = 1.4917X + 0.9100, R2 = 0.9948) with a limit of detection (LOD) of 0.3393 ng/mL. The sensor was successfully used to evaluate the content of SEA in milk samples, and the recovery efficiency of SEA was between 87.70% and 94.65%. Thus, the sensor shows great potential for application in food analysis. In short, the proposed platform consisted of an aptamer fluorescent sensor that can be used for the ultrasensitive detection of various toxins by taking advantage of the excellent affinity and specificity of corresponding aptamers.

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Mira Miralles, Marina, Lucia Maestre-Carballa, Monica Lluesma-Gomez, and Manuel Martinez-Garcia. "High-Throughput 16S rRNA Sequencing to Assess Potentially Active Bacteria and Foodborne Pathogens: A Case Example in Ready-to-Eat Food." Foods 8, no. 10 (October 11, 2019): 480. http://dx.doi.org/10.3390/foods8100480.

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Technologies to detect the entire bacterial diversity spectra and foodborne pathogens in food represent a fundamental advantage in the control of foodborne illness. Here, we applied high-throughput 16S rRNA sequencing of amplicons obtained by PCR and RT-PCR from extracted DNA and RNA targeting the entire bacterial community and the active bacterial fraction present in some of the most consumed and distributed ready-to-eat (RTE) salad brands in Europe. Customer demands for RTE food are increasing worldwide along with the number of associated foodborne illness and outbreaks. The total aerobic bacterial count in the analyzed samples was in the range of 2–4 × 106 CFU/g (SD ± 1.54 × 106). Culture validated methods did not detect Salmonella spp., Escherichia coli, and other fecal coliforms. 16S rRNA gene Illumina next-generation sequencing (NGS) data were congruent with these culture-based results and confirmed that these and other well-known foodborne bacterial pathogens, such as Listeria, were not detected. However, the fine-resolution of the NGS method unveiled the presence of the opportunistic pathogens Aeromonas hydrophyla and Rahnella aquatilis (relative frequency of 1.33–7.33%) that were metabolically active in addition to non-pathogenic, active members of Yersinia spp. (relative frequency of 0.0015–0.003%). The common ail and foxA marker genes of Yersinia enterocolitica were not detected by qPCR. Finally, our NGS data identified to non-pathogenic Pseudomonas spp. as the most abundant and metabolically active bacteria in the analyzed RTE salads (53–75% of bacterial abundance). Our data demonstrate the power of sequencing, in parallel, both 16S rRNA and rDNA to identify and discriminate those potentially and metabolically active bacteria and pathogens to provide a more complete view that facilitates the control of foodborne diseases, although further work should be conducted to determine the sensitivity of this method for targeting bacteria

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Karus, Avo, Fabrizio Ceciliani, Armand Sanches Bonastre, and Virge Karus. "Development of Simple Multiplex Real-Time PCR Assays for Foodborne Pathogens Detection and Identification On Lightcycler." Macedonian Veterinary Review 40, no. 1 (March 1, 2017): 53–58. http://dx.doi.org/10.1515/macvetrev-2017-0010.

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Abstract Most acute intestinal diseases are caused by food-borne pathogens. A fast and simple real-time PCR-based procedure for simultaneous detection of food contamination by any of the five food-borne pathogens: Campylobacter jejuni, Mycobacterium bovis, Enterobacter sakazaki, Shigella boydii, Clostridium perfrigens using multiplex EvaGreen real-time PCR for LightCycler was developed and evaluated. Real-time qPCR showed excellent sensitivity. Tm calling and Melting Curve Genotyping (MCG) were used for analysis of PCR product melting curves. The Melting Curve Genotyping option showed good performance for discrimination of positive samples containing DNA of single pathogen or pathogen mixtures from negative samples.

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Vizzini, Priya, Matteo Braidot, Jasmina Vidic, and Marisa Manzano. "Electrochemical and Optical Biosensors for the Detection of Campylobacter and Listeria: An Update Look." Micromachines 10, no. 8 (July 27, 2019): 500. http://dx.doi.org/10.3390/mi10080500.

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Foodborne safety has aroused tremendous research interest in recent years because of a global public health problem. The rapid and precise detection of foodborne pathogens can reduce significantly infection diseases and save lives by the early initiation of an effective treatment. This review highlights current advances in the development of biosensors for detection of Campylobacter spp. and Listeria monocytogenes that are the most common causes of zoonosis. The consumption of pathogen contaminated food is responsible for humans hospitalization and death. The attention focused on the recognition elements such as antibodies (Ab), DNA probes and aptamers able to recognize cells, amplicons, and specific genes from different samples like bacteria, food, environment and clinical samples. Moreover, the review focused on two main signal-transducing mechanisms, i.e., electrochemical, measuring an amperometric, potentiometric and impedimetric signal; and optical, measuring a light signal by OLED (Organic Light Emitting Diode), SPR (Surface Plasmon Resonance), and Optical fiber. We expect that high-performance of devices being developed through basic research will find extensive applications in environmental monitoring, biomedical diagnostics, and food safety.

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BORGES, KAREN APELLANIS, THALES QUEDI FURIAN, SARA NEVES de SOUZA, EDUARDO CÉSAR TONDO, ANDRÉ FELIPE STRECK, CARLOS TADEU PIPPI SALLE, HAMILTON LUIZ de SOUZA MORAES, and VLADIMIR PINHEIRO do NASCIMENTO. "Spread of a Major Clone of Salmonella enterica Serotype Enteritidis in Poultry and in Salmonellosis Outbreaks in Southern Brazil." Journal of Food Protection 80, no. 1 (December 22, 2016): 158–63. http://dx.doi.org/10.4315/0362-028x.jfp-16-299.

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ABSTRACT Salmonella spp. are among the most important agents of foodborne diseases all over the world. Human Salmonella outbreaks are often associated with the consumption of poultry products (meat and eggs), and one of the most prevalent serotypes associated with these products is Salmonella Enteritidis. Brazil is one of the most important poultry exporters in the world. In southern Brazil, three closely related clones of Salmonella Enteritidis have been responsible for the majority of foodborne Salmonella outbreaks over the past decade. However, until now, there has been little information regarding the clonal relationship among the Brazilian Salmonella strains of avian origin and those involved in foodborne outbreaks. Therefore, the aim of the present study was to complete the molecular characterization of Salmonella Enteritidis strains isolated from poultry and food sources involved in Salmonella outbreaks. PCR ribotyping was performed to discriminate the strains into different ribotype profiles according to the banding pattern amplification. This technique was able to differentiate the Salmonella Enteritidis strains into two banding patterns: R2 and R4. R2 accounted for 98.7% of the strains. DNA sequencing of the 600-bp fragment, present in all ribotypes, was applied to confirm this result. The sequences generated showed high levels of similarity, ranging from 99.7 to 100%, and were grouped into a single cluster. These results suggest that there is a clonal relationship among the Salmonella Enteritidis strains responsible for several salmonellosis outbreaks and the strains collected from poultry sources.

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Moura, Tiane Martin de, Fabrício Souza Campos, Pedro Alves d'Azevedo, Sueli Teresinha Van Der Sand, Ana Cláudia Franco, Jeverson Frazzon, and Ana Paula Guedes Frazzon. "Prevalence of enterotoxin-encoding genes and antimicrobial resistance in coagulase-negative and coagulase-positive Staphylococcus isolates from black pudding." Revista da Sociedade Brasileira de Medicina Tropical 45, no. 5 (October 2012): 579–85. http://dx.doi.org/10.1590/s0037-86822012000500008.

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INTRODUCTION: Staphylococcal species are pathogens that are responsible for outbreaks of foodborne diseases. The aim of this study was to investigate the prevalence of enterotoxin-genes and the antimicrobial resistance profile in staphylococcus coagulase-negative (CoNS) and coagulasepositive (CoPS) isolates from black pudding in southern Brazil. METHODS: Two hundred typical and atypical colonies from Baird-Parker agar were inoculated on mannitol salt agar. Eighty-two mannitol-positive staphylococci were submitted to conventional biochemical tests and antimicrobial susceptibility profiling. The presence of coagulase (coa) and enterotoxin (se) genes was investigated by polymerase chain reaction. RESULTS: The isolates were divided into 2 groups: 75.6% (62/82) were CoNS and 24.4% (20/82) were CoPS. The biochemical tests identified 9 species, of which Staphylococcus saprophyticus (37.8%) and Staphylococcus carnosus (15.9%) were the most prevalent. Antimicrobial susceptibility tests showed resistance phenotypes to antibiotics widely administered in humans, such as gentamicin, tetracycline, chloramphenicol, and erythromycin. The coa gene was detected in 19.5% (16/82) of the strains and 4 polymorphic DNA fragments were observed. Five CoNS isolates carrying the coa gene were submitted for 16S rRNA sequencing and 3 showed similarity with CoNS. Forty strains were positive for at least 1 enterotoxin-encoding gene, the genes most frequently detected were sea (28.6%) and seb (27.5%). CONCLUSIONS: The presence of antimicrobial resistant and enterotoxin-encoding genes in staphylococci isolates from black pudding indicated that this fermented food may represent a potential health risk, since staphylococci present in food could cause foodborne diseases or be a possible route for the transfer of antimicrobial resistance to humans.

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ESPINOZA-MEDINA, I. E., F. J. RODRÍGUEZ-LEYVA, I. VARGAS-ARISPURO, M. A. ISLAS-OSUNA, E. ACEDO-FÉLIX, and M. A. MARTÍNEZ-TÉLLEZ. "PCR Identification of Salmonella: Potential Contamination Sources from Production and Postharvest Handling of Cantaloupes." Journal of Food Protection 69, no. 6 (June 1, 2006): 1422–25. http://dx.doi.org/10.4315/0362-028x-69.6.1422.

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Salmonella is one of the most frequently reported etiological agents in outbreaks of foodborne diseases associated with the consumption of cantaloupes. Sensitive and reliable methods for detecting and identifying foodborne microorganisms are needed. The PCR can be used to amplify specific DNA fragments and thus to detect and identify pathogenic bacteria. In this study, a PCR method was used to evaluate the incidence of Salmonella at cantaloupe production, harvest, and packaging steps, and the results were compared with those of the standard method for detection of Salmonella in foods (Mexican NOM-114-SSA1-1994). Salmonella was detected by both standard and PCR methods in 23.5% of the irrigation water samples but only by the PCR method in 9.1% of the groundwater samples, 4.8% of the chlorinated water samples, 16.7% of samples from the hands of packing workers, 20.6% of samples from the packed cantaloupes, and 25.7% of samples from the in-field cantaloupes. With the standard method, Salmonella was found in 8.3% of the crop soil samples. Statistical analysis indicated a significant difference in sensitivity (P <0.05) between the two methods; the PCR method was 4.3 times more sensitive than the standard method. Salmonella was found at seven of the eight points evaluated during the production and postharvest handling of cantaloupe melons.

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PETERS, T. M., C. BERGHOLD, D. BROWN, J. COIA, A. M. DIONISI, A. ECHEITA, I. S. T. FISHER, et al. "Relationship of pulsed-field profiles with key phage types of Salmonella enterica serotype Enteritidis in Europe: results of an international multi-centre study." Epidemiology and Infection 135, no. 8 (February 19, 2007): 1274–81. http://dx.doi.org/10.1017/s0950268807008102.

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SUMMARYSalmonella is one of the most common causes of foodborne infection in Europe with Salmonella enterica serovar Enteritidis (S. Enteritidis) being the most commonly identified serovar. The predominant phage type for S. Enteritidis is phage type (PT) 4, although PT 8 has increased in incidence. Within these phage types, pulsed-field gel electrophoresis (PFGE) provides a method of further subdivision. The international project, Salm-gene, was established in 2001 to develop a database of PFGE profiles within nine European countries and to establish criteria for real-time pattern recognition. It uses DNA fingerprints of salmonellas to investigate outbreaks and to evaluate trends and emerging issues of foodborne infection within Europe. The Salm-gene database contains details of about 11 700 S. Enteritidis isolates, demonstrating more than 65 unique PFGE profiles. The clonal nature of S. Enteritidis is evidenced by the high similarity and distribution of PFGE profiles. Over 56% (6603/11 716) of the submitted isolates of several different phage types were profile SENTXB.0001, although this profile is most closely associated with PT 4. The next most common profiles, SENTXB.0002 and SENTXB.0005, were closely associated with PT 8 and PT 21 respectively. Studies to investigate the relationship of profile types with outbreaks and possible vehicles of infection suggest that the incidence of PFGE profile SENTXB.0002, and thus PT 8, in some countries may be due to importation of foods or food production animals from Eastern Europe, where PT 8 is amongst the most frequently identified phage types. Collation of subtyping data, especially in the commonly recognized phage types, is necessary in order to evaluate trends and emerging issues in salmonella infection.

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Jahan, Nusrat A., Laramie L. Lindsey, Evan J. Kipp, Adam Reinschmidt, Bradley J. Heins, Amy M. Runck, and Peter A. Larsen. "Nanopore-Based Surveillance of Zoonotic Bacterial Pathogens in Farm-Dwelling Peridomestic Rodents." Pathogens 10, no. 9 (September 13, 2021): 1183. http://dx.doi.org/10.3390/pathogens10091183.

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The effective control of rodent populations on farms is crucial for food safety, as rodents are reservoirs and vectors for several zoonotic pathogens. Clear links have been identified between rodents and farm-level outbreaks of pathogens throughout Europe and Asia; however, comparatively little research has been devoted to studying the rodent–agricultural interface in the USA. Here, we address this knowledge gap by metabarcoding bacterial communities of rodent pests collected from Minnesota and Wisconsin food animal farms. We leveraged the Oxford Nanopore MinION sequencer to provide a rapid real-time survey of putative zoonotic foodborne pathogens, among others. Rodents were live trapped (n = 90) from three dairy and mixed animal farms. DNA extraction was performed on 63 rodent colons along with 2 shrew colons included as outgroups in the study. Full-length 16S amplicon sequencing was performed. Our farm-level rodent-metabarcoding data indicate the presence of multiple foodborne pathogens, including Salmonella spp., Campylobacter spp., Staphylococcus aureus, and Clostridium spp., along with many mastitis pathogens circulating within five rodent species (Microtus pennsylvanicus, Mus musculus, Peromyscus leucopus, Peromyscus maniculatus, and Rattus norvegicus) and a shrew (Blarina brevicauda). Interestingly, we observed a higher abundance of enteric pathogens (e.g., Salmonella) in shrew feces compared to the rodents analyzed in our study. Knowledge gained from our research efforts will directly inform and improve farm-level biosecurity efforts and public health interventions to reduce future outbreaks of foodborne and zoonotic disease.

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ZHANG, JING, BIAO DI, HONGBO SHAN, JUNHUA LIU, YONG ZHOU, HUILING CHEN, LIN HU, XINWEI WU, and ZHIJUN BAI. "Rapid Detection of Bacillus cereus Using Cross-Priming Amplification." Journal of Food Protection 82, no. 10 (September 19, 2019): 1744–50. http://dx.doi.org/10.4315/0362-028x.jfp-19-156.

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ABSTRACT Bacillus cereus is a spore-forming gastrointestinal pathogen that can cause life-threatening diseases. Here, a simple and effective assay to detect B. cereus was developed, using cross-priming amplification (CPA). Amplicons were detected using disposable cartridges that contained nucleic acid detection strips. The sensitivity of CPA assay for B. cereus was assessed using serial dilutions of genomic DNA, which indicated a detection limit of 3.6 × 101 CFU/mL. No cross-reactions were detected when genomic DNA extracted from 12 different B. cereus strains and 20 other bacterial foodborne strains were tested, suggesting that the assay is highly specific. Finally, we evaluated the practical applications of the CPA assay for the detection of B. cereus in 150 food samples and found that its sensitivity and specificity, compared with real-time PCR, were approximately 98.18 and 100%, respectively. In conclusion, CPA combined with nucleic acid detection strips is easy to perform, requires simple equipment, and offers highly specific and sensitive B. cereus detection.

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Mthembu, Zishiri, and Zowalaty. "Detection and Molecular Identification of Salmonella Virulence Genes in Livestock Production Systems in South Africa." Pathogens 8, no. 3 (August 9, 2019): 124. http://dx.doi.org/10.3390/pathogens8030124.

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Livestock are an important source of protein and food for humans, however opportunistic pathogens such as Salmonella spp. turn livestock into vehicles of foodborne diseases. This study investigated the prevalence of virulence genes in Salmonella spp. isolated from livestock production systems in two provinces of South Africa. During the period from May to August, 2018, a total of 361 faecal (189), oral (100), environmental (soil (36) and water (27)) and feed (9) samples were randomly collected from different animals (cattle, sheep, goats, pigs, ducks and chickens) that were housed in small-scale livestock production systems from Eastern Cape and KwaZulu-Natal Provinces in South Africa. Salmonella spp. were isolated and identified using microbiological and DNA molecular methods. Salmonella spp. were present in 29.0% of the samples of which 30.2% belonged to the Salmonella enterica species as confirmed by the positive amplification of the species specific iroB gene. Virulence genes that were screened from livestock-associated Salmonella were invA, iroB, spiC, pipD and int1. Statistically significant associations (p < 0.05) were established between the virulence genes, sampling location, animal host as well as the season when samples were collected. Furthermore, statistically significant (p < 0.05) positive correlations were observed between most of the virulence genes investigated. This is one of the recent studies to detect and investigate livestock-associated Salmonella spp. in South Africa. This study highlights the importance of continuous monitoring and surveillance for pathogenic salmonellae. It also demonstrated the detection and prevalence of virulent Salmonella spp. harbored by livestock in South Africa. This study demonstrated the potential risks of pathogenic Salmonella enterica to cause foodborne diseases and zoonotic infections from farm-to-fork continuum using the global one-health approach.

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Ramarao, Nalini, Seav-Ly Tran, Marco Marin, and Jasmina Vidic. "Advanced Methods for Detection of Bacillus cereus and Its Pathogenic Factors." Sensors 20, no. 9 (May 7, 2020): 2667. http://dx.doi.org/10.3390/s20092667.

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Bacillus cereus is an opportunistic foodborne pathogen causing food intoxication and infectious diseases. Different toxins and pathogenic factors are responsible for diarrheal syndrome, like nonhemolytic enterotoxin Nhe, hemolytic enterotoxin Hbl, enterotoxin FM and cytotoxin K, while emetic syndrome is caused by the depsipeptide cereulide toxin. The traditional method of B. cereus detection is based on the bacterial culturing onto selective agars and cells enumeration. In addition, molecular and chemical methods are proposed for toxin gene profiling, toxin quantification and strain screening for defined virulence factors. Finally, some advanced biosensors such as phage-based, cell-based, immunosensors and DNA biosensors have been elaborated to enable affordable, sensitive, user-friendly and rapid detection of specific B. cereus strains. This review intends to both illustrate the state of the B. cereus diagnostic field and to highlight additional research that is still at the development level.

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Pons, Benoît J., Aurélie Pettes-Duler, Claire Naylies, Frédéric Taieb, Catherine Bouchenot, Saleha Hashim, Patrick Rouimi, et al. "Chronic exposure to Cytolethal Distending Toxin (CDT) promotes a cGAS-dependent type I interferon response." Cellular and Molecular Life Sciences 78, no. 17-18 (July 25, 2021): 6319–35. http://dx.doi.org/10.1007/s00018-021-03902-x.

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AbstractThe Cytolethal Distending Toxin (CDT) is a bacterial genotoxin produced by pathogenic bacteria causing major foodborne diseases worldwide. CDT activates the DNA Damage Response and modulates the host immune response, but the precise relationship between these outcomes has not been addressed so far. Here, we show that chronic exposure to CDT in HeLa cells or mouse embryonic fibroblasts promotes a strong type I interferon (IFN) response that depends on the cytoplasmic DNA sensor cyclic guanosine monophosphate (GMP)-adenosine monophosphate (AMP) synthase (cGAS) through the recognition of micronuclei. Indeed, despite active cell cycle checkpoints and in contrast to other DNA damaging agents, cells exposed to CDT reach mitosis where they accumulate massive DNA damage, resulting in chromosome fragmentation and micronucleus formation in daughter cells. These mitotic phenotypes are observed with CDT from various origins and in cancer or normal cell lines. Finally, we show that CDT exposure in immortalized normal colonic epithelial cells is associated to cGAS protein loss and low type I IFN response, implying that CDT immunomodulatory function may vary depending on tissue and cell type. Thus, our results establish a direct link between CDT-induced DNA damage, genetic instability and the cellular immune response that may be relevant in the context of natural infection associated to chronic inflammation or carcinogenesis.

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Khambaty, F. M., R. W. Bennett, and D. B. Shah. "Application of pulsed-field gel electrophoresis to the epidemiological characterization ofStaphylococcus intermediusimplicated in a food-related outbreak." Epidemiology and Infection 113, no. 1 (August 1994): 75–81. http://dx.doi.org/10.1017/s0950268800051487.

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SUMMARYAn outbreak of food intoxication involving over 265 cases in western United States occurred in October 1991.Staphylococcus intermediuswas implicated as the aetiologic agent. Representative outbreak isolates (five clinical and ten from foods) produced type A enterotoxin. DNA fragments generated by four restriction endonucleases and analysed by pulsed-field gel electrophoresis (PFGE) provided definitive evidence that all isolates from nine different counties in California and Nevada were derived from a single strain. The PFGE pattern of these outbreak isolates was distinct from those of a heterogeneous collection of sevenS. intermediusstrains of veterinary origin and five unrelatedS. aureuslaboratory strains. The data show a significant PFGE pattern heterogeneity not only among members of differentStaphylococcusspecies but also within members of the same species and even the same enterotoxin type. The results indicate that PFGE is a valuable strain-specific discriminator for the epidemiological characterization ofS. intermedius. To our knowledge, this represents the first documented foodborne outbreak caused byS. intermedius. These findings suggest that the presence ofS. intermediusand other species such asS. hyicusin food should be reason for concern.

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Qvarnstrom, Yvonne, Theresa Benedict, Paula L. Marcet, Ryan E. Wiegand, Barbara L. Herwaldt, and Alexandre J. da Silva. "Molecular detection ofCyclospora cayetanensisin human stool specimens using UNEX-based DNA extraction and real-time PCR." Parasitology 145, no. 7 (November 8, 2017): 865–70. http://dx.doi.org/10.1017/s0031182017001925.

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AbstractCyclospora cayetanensisis a coccidian parasite associated with diarrheal illness. In the USA, foodborne outbreaks of cyclosporiasis have been documented almost every year since the mid-1990s. The typical approach used to identify this parasite in human stools is an examination of acid-fast-stained smears under bright-field microscopy. UV fluorescence microscopy of wet mounts is more sensitive and specific than acid-fast staining but requires a fluorescence microscope with a special filter not commonly available in diagnostic laboratories. In this study, we evaluated a new DNA extraction method based on the Universal Nucleic Acid Extraction (UNEX) buffer and compared the performances of four published real-time polymerase chain reaction (PCR) assays for the specific detection ofC. cayetanensisin stool. The UNEX-based method had an improved capability to recover DNA from oocysts compared with the FastDNA stool extraction method. The best-performing real-time PCR assay was aC. cayetanensis-specific TaqMan PCR that targets the 18S ribosomal RNA gene. This new testing algorithm should be useful for detection ofC. cayetanensisin human stool samples.

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Pons, Benoît J., Nicolas Loiseau, Saleha Hashim, Soraya Tadrist, Gladys Mirey, and Julien Vignard. "Functional Study of Haemophilus ducreyi Cytolethal Distending Toxin Subunit B." Toxins 12, no. 9 (August 19, 2020): 530. http://dx.doi.org/10.3390/toxins12090530.

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The Cytolethal Distending Toxin (CDT) is produced by many Gram-negative pathogenic bacteria responsible for major foodborne diseases worldwide. CDT induces DNA damage and cell cycle arrest in host-cells, eventually leading to senescence or apoptosis. According to structural and sequence comparison, the catalytic subunit CdtB is suggested to possess both nuclease and phosphatase activities, carried by a single catalytic site. However, the impact of each activity on cell-host toxicity is yet to be characterized. Here, we analyze the consequences of cell exposure to different CDT mutated on key CdtB residues, focusing on cell viability, cell cycle defects, and DNA damage induction. A first class of mutant, devoid of any activity, targets putative catalytic (H160A), metal binding (D273R), and DNA binding residues (R117A-R144A-N201A). The second class of mutants (A163R, F156-T158, and the newly identified G114T), which gathers mutations on residues potentially involved in lipid substrate binding, has only partially lost its toxic effects. However, their defects are alleviated when CdtB is artificially introduced inside cells, except for the F156-T158 double mutant that is defective in nuclear addressing. Therefore, our data reveal that CDT toxicity is mainly correlated to CdtB nuclease activity, whereas phosphatase activity may probably be involved in CdtB intracellular trafficking.

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Zhang, Zilei, Danlei Liu, Dapeng Wang, and Qingping Wu. "Library Preparation Based on Transposase Assisted RNA/DNA Hybrid Co-Tagmentation for Next-Generation Sequencing of Human Noroviruses." Viruses 13, no. 1 (January 6, 2021): 65. http://dx.doi.org/10.3390/v13010065.

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Human noroviruses (HuNoVs) are one of the leading causes of foodborne illnesses globally. The viral genome is the most essential information for viral source tracing and viral transmission pattern monitoring. However, whole genome sequencing of HuNoVs is still challenging due to the sequence heterogeneity among different genotypes and low titer in samples. To address this need, in this study, the Transposase assisted RNA/DNA hybrid Co-tagmentation (TRACE-seq) method was established for next generation sequencing library preparation of HuNoVs. Our data demonstrated that almost the whole HuNoVs genome (>7 kb) could be obtained from all of the 11 clinical samples tested. Twelve genotypes including GI.3, GI.4, GI.5, GI.8, GII.2, GII.3, GII.4, GII.6, GII.12, GII.13, GII.14, and GII.21 were involved. Compared with the traditional method for viral metagenomics library preparation, optimized TRACE-seq greatly reduced the interference from the host’s and bacterial RNAs. In addition, viral genome sequences can be assembled by using less raw data with sufficient depth along the whole genome. Therefore, for the high versatility and reliability, this method is promising for whole viral genome attainment. It is particularly applicable for the viruses with a low titer that are mixed with a complicated host background and are unable to be cultured in vitro, like the HuNoVs utilized in this study.

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Sawadpanich, Kookwan, Nitiwat Chansuk, Patcharaporn Boonroumkaew, Lakkhana Sadaow, Rutchanee Rodpai, Oranuch Sanpool, Penchom Janwan, Pewpan M. Intapan, and Wanchai Maleewong. "An Unusual Case of Gastric Gnathostomiasis Caused by Gnathostoma spinigerum Confirmed by Video Gastroscopy and Morphological and Molecular Identification." American Journal of Tropical Medicine and Hygiene 104, no. 6 (June 2, 2021): 2050–54. http://dx.doi.org/10.4269/ajtmh.21-0015.

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Abstract.Human gnathostomiasis is a harmful foodborne parasitic infection caused by nematodes of the genus Gnathostoma. Here, we report an unusual case of gastric gnathostomiasis seen in a hospital in Thailand along with the clinical characteristics, treatment, and outcome. A 39-year-old man presented with complaints of epigastric pain, dizziness, and history of passing dark, tarry stools for 2 days. The patient had a history of consuming raw freshwater fish. Supplementary differential diagnosis was performed via rapid serological testing, and presence of the causative agent was confirmed based on video gastroscopy, morphology of the removed parasite, and molecular identification. After its surgical removal from the stomach, the parasite was morphologically identified as Gnathostoma species. Molecular identification was performed via DNA extraction from the recovered worm, and amplification and sequencing of the second internal transcribed spacer (ITS2) region and partial cytochrome c oxidase subunit I (cox1) gene. The ITS2 and cox1 sequences were consistent with those of Gnathostoma spinigerum. Clinicians in endemic areas should therefore be aware of the rare clinical manifestations and use of supplementary serological tests to facilitate early diagnosis and treatment of gastric gnathostomiasis.

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Yu, Tao, Xiaojie Jiang, Qiaohong Zhou, Junmei Wu, and Zhenbin Wu. "Antimicrobial resistance, class 1 integrons, and horizontal transfer in Salmonella isolated from retail food in Henan, China." Journal of Infection in Developing Countries 8, no. 06 (June 11, 2014): 705–11. http://dx.doi.org/10.3855/jidc.4190.

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Introduction: Salmonellosis remains one of the most frequently occurring foodborne diseases worldwide, especially in developing countries. The increasing prevalence of multidrug resistance among Salmonella isolates from food has been an emerging problem in China. Methodology: In this study, a total of 638 food samples including raw meat, seafood, vegetables, and cooked meat were collected in Henan province of China between July 2007 and August 2008 to determine the prevalence of Salmonella. These isolates were subjected to serotyping, antimicrobial susceptibility, presence of class 1 integrons, and horizontal transfer of integrons. Results: The overall percentage of Salmonella prevalence was 9.7% (n = 62). Among these isolates, S. Anatum and S. Senftenberg were most common, and high rates of antimicrobial resistance were observed to sulfamethoxazole (90.3%), trimethoprim/sulfamethoxazole (87.1%), streptomycin (29.0%), and ciprofloxacin (25.8%). Class 1 integrons were detected in 16.1% of these isolates, and contained gene cassettes dfrA12-aadA2, dfrA1-aadA1, and dfrA1. Three Salmonella isolates could transfer their integrons and resistance genes to Escherichia coli by conjugation. Conclusions: Our findings indicate that the mobile DNA elements could play an important role in the dissemination of resistance determinants among those Salmonella isolates.

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HASSENA, AMAL BEN, MARIAM SIALA, SONDA GUERMAZI, SONIA ZORMATI, RADHOUANE GDOURA, and HANEN SELLAMI. "Occurrence and Phenotypic and Molecular Characterization of Antimicrobial Resistance of Salmonella Isolates from Food in Tunisia." Journal of Food Protection 82, no. 7 (June 24, 2019): 1166–75. http://dx.doi.org/10.4315/0362-028x.jfp-18-607.

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ABSTRACT Salmonella is a leading cause of foodborne diseases worldwide. The use of antibiotics in food-producing animals may contribute to the development of antimicrobial resistance in nontyphoidal Salmonella. The development of resistance to potent antimicrobials such as fluoroquinolones and extended-spectrum β-lactamases is a significant public health problem. The present study was conducted to examine the occurrence and antimicrobial resistance of Salmonella isolates obtained from food samples. Salmonella was cultured according to ISO 6579:2002 method, and antimicrobial resistance was evaluated with the Kirby-Bauer disk diffusion method. Forty-five Salmonella isolates were recovered, and a high Salmonella prevalence was detected in clams (7 of 20 samples, 35%), chicken (28 of 97 samples, 28.9%) and cow's milk (10 of 80 samples, 12.5%). Salmonella Enteritidis (n = 19) and Salmonella Kentucky (n = 18) were the most prevalent isolates. Multidrug resistance was found in 31.1% of the isolates (14 of 45); 84, 46, 28, and 17% of the isolates were resistant to nalidixic acid, ciprofloxacin, amoxicillin–clavulanic acid, and both ofloxacin and cefotaxime, respectively. The isolates resistant to cefotaxime were screened by PCR for the genes for TEM β-lactamase, extended-spectrum β-lactamases (CTX and OXA), and AmpC β-lactamases (FOX, MOX, DHA, ACC, CIT, and EBC). One Salmonella Kentucky isolate from milk harbored an AmpC gene (FOX), and the same serotype isolated from chicken carried the EBC AmpC determinant. The blaTEM gene was detected in all nonsusceptible isolates. We also screened isolates with reduced fluoroquinolone susceptibility for the presence of transferable plasmid-mediated quinolone resistance determinants. Three qnr genes (qnrB, qnrD, and qnrS) were detected in four isolates (two from milk and two from chicken). To our knowledge, this is the first report of the AmpC FOX and EBC gene families and the qnrD gene within a foodborne pathogen in Tunisia. These findings highlight the emergence of multidrug-resistant Salmonella isolates with decreased susceptibility to fluoroquinolones and third-generation cephalosporins, which are drugs commonly used for the treatment of Salmonella infections. HIGHLIGHTS

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Kobayashi, Patrícia De Freitas, Aline Feola de Carvalho, Rodrigo César Fredrigo, Andréa Moura Costa, Rosa Maria Piatti, and Eliana Scarcelli Pinheiro. "Detection of Brucella spp., Campylobacter spp. and Listeria monocytogenes in raw milk and cheese of uninspected production in the metropolitan area of São Paulo." Semina: Ciências Agrárias 38, no. 4 (August 4, 2017): 1897. http://dx.doi.org/10.5433/1679-0359.2017v38n4p1897.

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Foodborne diseases are a major public health issue but their overall incidence is underestimated due to insufficient report. The present study aimed to investigate the presence of Brucella spp., Campylobacter spp. and Listeria monocytogenes in raw milk and cheese of uninspected production obtained from cattle bred on the polluted banks of the Tietê River. Generally, milk from these animals is used to prepare fresh cheese, which is then commercialized by the producers themselves or in local markets. We analyzed 81 samples consisting of 38 samples of cheeses, 15 samples of raw milk and 28 samples of water collected from the Tietê River. These samples were evaluated for the presence of the three pathogens using bacteriological methods and the conventional polymerase chain reaction (PCR), with primers specific for each bacterial genus. In the bacteriological examination, all samples were negative for Brucella spp., Campylobacter spp. and Listeria monocytogenes. In the PCR test, Brucella spp. was detected in 5/38 (13.16%) cheese samples. Campylobacter spp. was present in 18/38 (47.37%) cheese samples, 1/15 (6.66%) raw milk samples and in 12/28 (42.86%) water samples. Listeria monocytogenes was not detected by PCR. The detection of Brucella spp. DNA in cheese and Campylobacter spp. DNA in cheese, milk and water may reflect inadequate animal sanitary management and deficiencies in good manufacturing practices. The presence of these pathogens in the food and water may pose a threat to the health of the consumer and increase the incidence of zoonosis.

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CHEN, Y., T. WEN, D. H. LAI, Y. Z. WEN, Z. D. WU, T. B. YANG, X. B. YU, G. HIDE, and Z. R. LUN. "Development and evaluation of loop-mediated isothermal amplification (LAMP) for rapid detection of Clonorchis sinensis from its first intermediate hosts, freshwater snails." Parasitology 140, no. 11 (July 22, 2013): 1377–83. http://dx.doi.org/10.1017/s0031182013000498.

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SUMMARYClonorchiasis, caused by Clonorchis sinensis, is a key foodborne zoonosis, which is mainly found in China, Korea and Vietnam. Detection of this parasite from the second intermediate host, the freshwater fish is the common method for epidemiological surveys of this parasite, but is time consuming, labour intensive and easily leads to misdiagnosis. In this study, we have developed a rapid, sensitive and reliable molecular method for the diagnosis of C. sinensis from its first intermediate hosts, freshwater snails, based on a loop-mediated isothermal amplification (LAMP) method. The specific amplified fragment from genomic DNA of C. sinensis did not cross-react with those from other relevant trematodes and a range of hosts (freshwater fish, shrimps and snails) of C. sinensis living in similar environments. The detection limit of the LAMP method was as low as 10 fg which was 1000 times more sensitive than conventional PCR, which was also demonstrated by successful application to field samples. These results show that the LAMP method is a more sensitive tool than conventional PCR for the detection of C. sinensis infection in the first intermediate hosts and, due to a simpler protocol, is an ideal molecular method for field-based epidemiological surveys of this parasite.

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Kawase, Jun, Yoshiki Etoh, Tetsuya Ikeda, Keiji Yamaguchi, Masanori Watahiki, Tomoko Shima, Mitsuhiro Kameyama, et al. "An Improved Multiplex Real-Time SYBR Green PCR Assay for Analysis of 24 Target Genes from 16 Bacterial Species in Fecal DNA Samples from Patients with Foodborne Illnesses." Japanese Journal of Infectious Diseases 69, no. 3 (2016): 191–201. http://dx.doi.org/10.7883/yoken.jjid.2015.027.

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Saadati, Amirhossein, Zohreh Mashak, and Mohammad Saeid Yarmand. "Prevalence of Staphylococcal Cassette Chromosome mec and Panton-Valentine Leukocidin Gene Amongst the Methicillin-resistant Staphylococcus aureus Strains Isolated From Fowl Meat." International Journal of Enteric Pathogens 7, no. 3 (August 30, 2019): 93–98. http://dx.doi.org/10.15171/ijep.2019.20.

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Background: Methicillin-resistant Staphylococcus aureus (MRSA) is considered to be one of the most important causes of foodborne diseases. Objective: The current examination was performed to examine the distribution of staphylococcal cassette chromosome mec (SCCmec) and Panton-Valentine leukocidin (PVL) gene amongst the MRSA strains isolated from raw fowl meat samples. Materials and Methods: A total of 240 fowl meat samples were collected and cultured. MRSA strains were identified using cefoxitin and oxacillin susceptibility tests. DNA samples extracted from the MRSA strains were subjected to polymerase chain reaction (PCR) for detection of SCCmec and PVL gene. Results: Twenty-two out of 240 (9.16%) raw fowl meat samples were positive for S. aureus strains. Twelve out of 22 S. aureus strains (54.54%) were determined as MRSA strains. The incidence of MRSA strains in raw chicken, turkey, quail, and ostrich meat samples was 66.66%, 50%, 50%, and 33.33%, respectively. The incidence of SCCmec IVa, SCCmec IVd, and SCCmec V was 50%, 8.33% and 41.66%, respectively. The applied method failed to detect SCCmec types I, II, III, IVb, and IVc. The incidence of the PVL gene amongst the MRSA strains was 75%. Conclusion: The presence of SCCmec IV and SCCmec V and PVL gene revealed occurrence of community-associated MRSA (CA-MRSA) in fowl meat samples. Further studies are required to find additional epidemiological aspects of the MRSA strains in fowl meat samples.

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Kusumaningsih, Purwaningtyas, and Ni Made Diaris. "BACTERIAL IDENTIFICATION ON MACKEREL TUNA (EUTHYNNUS AFFINIS) BRINE SALTING TRADED IN TRADISIONAL MARKET OF SEMARAPURA, KLUNGKUNG, BALI." Jurnal Veteriner 22, no. 1 (March 31, 2021): 68–78. http://dx.doi.org/10.19087/jveteriner.2021.22.1.68.

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Mackerel tuna (Euthynnus affinis) brine salting is a famous seafood product in Indonesia due to its good nutrition content. Bacterial contamination on this product may increase risk of foodborne diseases to happen, in addition to a decrease in quality and nutritionous value of the product. The main objective of this research was to identify bacteria contaminating the brine salting Mackerel tuna (Euthynnus affinis) sold in Tradisional Markets in Klungkung, Bali, Indonesia. Polymerase Chain Reaction (PCR) was apllied in the process of identification of bacterial contaminants. Samples were collected from 5 fish kiosks at the Tradisional market in Klungkung, Bali Indonesia. Each sample was cultured in Blood Agar or Nutrient Agar. Colonies with different morfology were selected, enriched in Tryptic Soy Broth (TSB), and their DNA was extracted before being amplified with 16S rRNA primers. This PCR products were then sequenced, and the results were compared with those available in the geneBank. Basic Local Alignment Search Tool was conducted with help of MEGA software version 6. Seven bacterial species were identified, and these included Serratia nematodiphila, Bacillus cereus, Shewanella seohaensis, Vibrio alginolyticus, Kurthia gibsonii, Enterobacter cloacae, and Staphylococcus sciuri. All but one Kurthia gibsonii are potensial pathogens in human. Staphylococcus sciuri is not commonly found in seafood. The present of such species in the mackerel tuna brine salting product was probably due to poor handling during the process and distribution.

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Bazhenova, A. E., O. S. Rudenko, M. A. Pesterev, N. A. Shcherbakova, and S. Yu Misteneva. "Identification of the yeast strain cystobasidium slooffiae isolated from the cake test sample." Food systems 4, no. 2 (July 22, 2021): 111–16. http://dx.doi.org/10.21323/2618-9771-2020-4-2-111-116.

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Nowadays, the problem of food safety and quality assurance throughout the product life cycle is topical in the whole world. According to the WHO data, foodborne diseases linked with consumption of unsafe food, including diseases caused by microbial pathogens, are common in many world countries and are still the main cause of morbidity and mortality. Therefore, prevention of the microbiological spoilage of food products is an important task in all food industry sectors. One of the ways for its solution is to carry out investigations to reveal potential sources of microbial contamination of food products including flour confectionery. Cakes are multi-component confectionery products. As a rule, they have the high moisture mass fraction, which conditions the presence of a favorable environment for the development of all types of microorganisms and contributes to the instability of this product type to the effects of environmental conditions during storage. In this study, yeast and mold counts were determined by growing cultures on the solid culture medium (Sabouraud). Pure cultures were isolated by the streak plate method. Stained and unstained microorganisms were examined by the microscopic method. Saccharolytic enzymes of the isolated bacterial cultures were identified using the Hiss’s culture media. Based on the analysis of the ribosomal gene sequence obtained by sequencing the DNA region encoding the ITS-D1/D2 rDNA region, an accurate identification of the strain was performed. The phylogenetic relationship analysis carried out using strains of closely related microorganisms showed that species Cystobasidium slooffiae was the closest relative of the studied strain. The source of Cystobasidium slooffiae was the environment. The detection of this strain indicates violations of the sanitary and hygienic condition of inventory, equipment, industrial premises, including hard-to-reach places, as well as violations of the hygiene rules by personnel; in addition, this indicates the high contamination of raw materials.

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Bai, Li, Jiayong Zhao, Xin Gan, Juan Wang, Xiuli Zhang, Shenghui Cui, Shengli Xia, et al. "Emergence and Diversity of Salmonella enterica Serovar Indiana Isolates with Concurrent Resistance to Ciprofloxacin and Cefotaxime from Patients and Food-Producing Animals in China." Antimicrobial Agents and Chemotherapy 60, no. 6 (March 21, 2016): 3365–71. http://dx.doi.org/10.1128/aac.02849-15.

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Salmonellosis is a major global foodborne infection, and strains that are resistant to a great variety of antibiotics have become a major public health concern. The aim of this study was to identify genes conferring resistance to fluoroquinolones and extended-spectrum β-lactams in nontyphoidalSalmonella(NTS) from patients and food-producing animals in China. In total, 133 and 21 NTS isolates from animals and humans, respectively, exhibiting concurrent resistance to ciprofloxacin and cefotaxime were cultured independently from 2009 to ∼2013. All of the isolates were identified, serotyped, and subjected to antimicrobial susceptibility testing. Importantly, the isolates with concurrent resistance to ciprofloxacin and cefotaxime all were confirmed asS. entericaserovar Indiana. The presence of fluoroquinolone resistance genes and extended-spectrum β-lactamases (ESBLs) was established by PCR and DNA sequencing. The occurrence and diversity of different genes conferring fluoroquinolone resistance [qepA,oqxAB, andaac(6′)-Ib-cr] with mutations in topoisomerase-encoding genes (gyrAandparC) and several ESBLs (including CTX-M-65, CTX-M-27, CTX-M-15, CTX-M-14, and CTX-M-14/CTX-M-15) were noteworthy. Genes located on mobile genetic elements were identified by conjugation and transformation. Pulsed-field gel electrophoresis, used to determine the genetic relationships between these isolates, generated 91 pulsotypes from 133 chicken isolates and 17 pulsotypes from the 21 clinical isolates that showed considerable diversity. Analysis of the pulsotypes obtained with the isolates showed some clones appeared to have existed for several years and had been disseminating between humans and food-producing animals. This study highlights the emergence of ciprofloxacin- and cefotaxime-resistantS. entericaserovar Indiana, posing a threat to public health.

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Liao, Yen-Te, Alexandra Salvador, Leslie A. Harden, Fang Liu, Valerie M. Lavenburg, Robert W. Li, and Vivian C. H. Wu. "Characterization of a Lytic Bacteriophage as an Antimicrobial Agent for Biocontrol of Shiga Toxin-Producing Escherichia coli O145 Strains." Antibiotics 8, no. 2 (June 5, 2019): 74. http://dx.doi.org/10.3390/antibiotics8020074.

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Shiga toxin-producing Escherichia coli (STEC) O145 is one of the most prevalent non-O157 serogroups associated with foodborne outbreaks. Lytic phages are a potential alternative to antibiotics in combatting bacterial pathogens. In this study, we characterized a Siphoviridae phage lytic against STEC O145 strains as a novel antimicrobial agent. Escherichia phage vB_EcoS-Ro145clw (Ro145clw) was isolated and purified prior to physiological and genomic characterization. Then, in vitro antimicrobial activity against an outbreak strain, E. coli O145:H28, was evaluated. Ro145clw is a double-stranded DNA phage with a genome 42,031 bp in length. Of the 67 genes identified in the genome, 21 were annotated with functional proteins, none of which were stx genes. Ro145clw had a latent period of 21 min and a burst size of 192 phages per infected cell. The phage could sustain a wide range of pH (pH 3 to pH 10) and temperatures (−80 °C to −73 °C). Ro145clw was able to reduce E. coli O145:H28 in lysogeny broth by approximately 5 log at 37 °C in four hours. These findings indicate that the Ro145clw phage is a promising antimicrobial agent that can be used to control E. coli O145 in adverse pH and temperature conditions.

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DEER, DEANNE M., and KEITH A. LAMPEL. "Development of a Multiplex Real-Time PCR Assay with Internal Amplification Control for the Detection of Shigella Species and Enteroinvasive Escherichia coli." Journal of Food Protection 73, no. 9 (September 1, 2010): 1618–25. http://dx.doi.org/10.4315/0362-028x-73.9.1618.

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Shigella species, particularly S. sonnei and S. flexneri, remain some of the leading bacterial etiological agents of gastrointestinal diseases in the United States and globally. The isolation and detection of these foodborne pathogens are critical for preventing the spread of disease and facilitating epidemiological investigations aimed at determining the source of a Shigella infection outbreak. A multiplex real-time PCR-based assay was developed that targets all four species of Shigella plus enteroinvasive Escherichia coli. The assay incorporates primers directed to the ipaH genes located on both the virulence plasmid and chromosome, the plasmid-encoded virulence gene mxiC, a mutated mxiC gene (mxiC::kan) that differentiates wild-type strains from a laboratory control strain, and an internal amplification control. More than 50 isolates of all four Shigella species were tested for inclusivity and specificity of the multiplex PCR assay, and more than 30 non-Shigella isolates were tested for exclusivity of the assay. The sensitivity of the assay was 1 to 3 CFU and 5 to 50 fg of target (total) DNA for the ipaH, mxiC, and mxiC::kan gene targets. The assay performed equally well and with no measurable inhibition in the Shigella target reactions when rinsates of several high-risk produce commodities (parsley, cilantro, alfalfa sprouts, and lettuce) were added to the reactions. This multiplex PCR assay is sensitive and specific and has the added dimension of discriminating all Shigella species from the positive control strain so that in any sample analysis other strains can be excluded as a source of contamination.

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Pascal, Stefanía B., Juan R. Lorenzo Lopez, Paula M. A. Lucchesi, and Alejandra Krüger. "Subtypes of NanS-p Sialate O-Acetylesterase Encoded by Stx2a Bacteriophages." Proceedings 66, no. 1 (January 4, 2021): 15. http://dx.doi.org/10.3390/proceedings2020066015.

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Shiga toxin (Stx)-producing Escherichia coli strains are foodborne pathogens that can cause severe human diseases, such as haemorrhagic colitis and haemolytic uraemic syndrome. Stxs are encoded by bacteriophages (Stx phages) which show remarkable variations in genome composition and harbour several genes of unknown function. Recently, a gene encoding a sialate O-acetylesterase (NanS-p) was identified in some relevant Stx2a phages and it was suggested that it could provide advantages for bacterial growth in the gut. The aim of this study was to analyse the presence and sequence of nanS-p genes in available Stx2a phage genomes. A total of 59 DNA sequences of Stx2a phages were extracted from the NCBI GenBank database with the BLAST program using the stx2a sequence from phage 933W as a query sequence, either as complete phage genomes (45) or from bacterial genomes by subsequent analysis with the PHASTER web server (14). Comparative analysis revealed that nanS-p was located downstream of stx2a in all genomes. Twenty different amino acid sequences of NanS-p were identified. Specifically, catalytic esterase domains showed only 11 possible sequences, with differences mainly observed in nine amino acid positions. Sequences corresponding to the N-terminal domain (DUF1737) showed three possible sequences, two of them closely related, while the C-terminal domain was highly variable, with four groups with structural differences. Since sialate O-acetylesterase activity has been determined from particular Stx2a phages, new studies are necessary to evaluate if the NanS-p subtypes identified in the present study also differ in their biological activity.

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BAYSAL, AYSE HANDAN. "Comparison of Conventional Culture Method and Fluorescent In Situ Hybridization Technique for Detection of Listeria spp. in Ground Beef, Turkey, and Chicken Breast Fillets in İzmir, Turkey." Journal of Food Protection 77, no. 12 (December 1, 2014): 2021–30. http://dx.doi.org/10.4315/0362-028x.jfp-14-034.

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The occurrence of Listeria species in refrigerated fresh chicken breast fillet, turkey breast fillet, and ground beef was evaluated, comparing the conventional culture method and fluorescent in situ hybridization (FISH). FISH uses hybridization of a nucleic acid sequence target of a microorganism with a specific DNA probe labeled with a fluorochrome and imaging by a fluorescence microscope. First, Listeria was inoculated in chicken breast fillet, turkey breast fillet, or ground beef, and the applicability of the FISH method was evaluated. Second, Listeria was detected in fresh chicken breast fillet, turkey breast fillet, and ground beef by culture and FISH methods. Listeria was isolated from 27 (37.4%) of 216 samples by the standard culture method, whereas FISH detected 25 (24.7%) preenriched samples. Of these isolates, 17 (63%) were L. innocua, 6 (22%) L. welshimeri, and 4 (14.8%) L. seeligeri. Overall, the prevalences of Listeria spp. found with the conventional culture method in chicken breast fillet, turkey breast fillet, and ground beef were 9.7, 6.9, and 20.8%, whereas with the FISH technique these values were 11.1, 6.9, and 16.7%, respectively. The molecular FISH technique appears to be a cheap, sensitive, and time-efficient procedure that could be used for routine detection of Listeria spp. in meat. This study showed that retail raw meats are potentially contaminated with Listeria spp. and are, thus, vehicles for transmitting diseases caused by foodborne pathogens, underlining the need for increased precautions, such as implementation of hazard analysis and critical control points and consumer food safety education.

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JOHLER, SOPHIA, FRANZISKA LAYER, and ROGER STEPHAN. "Comparison of Virulence and Antibiotic Resistance Genes of Food Poisoning Outbreak Isolates of Staphylococcus aureus with Isolates Obtained from Bovine Mastitis Milk and Pig Carcasses." Journal of Food Protection 74, no. 11 (November 1, 2011): 1852–59. http://dx.doi.org/10.4315/0362-028x.jfp-11-192.

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Staphylococcus aureus is the etiological agent in a variety of infections in humans and livestock and produces enterotoxins leading to staphylococcal food poisoning (SFP), one of the most prevalent foodborne intoxication diseases worldwide. Pork and bovine milk are considered possible sources of SFP because pig skin is often colonized by S. aureus and bovine mastitis caused by S. aureus is common, but conclusive data are limited. The objective of the present study was to compare S. aureus isolates associated with cases of SFP with isolates obtained from bovine mastitis milk and pig carcasses. DNA microarray analysis and spa gene typing were performed with 100 S. aureus isolates: 20 isolates related to outbreaks of SFP in humans, 39 isolates obtained from pig carcasses, and 41 isolates collected from bovine mastitis milk. No overlap in spa types was observed for SFP isolates (t008, t015, t018, t024, t056, t084, t279, t377, t383, t648, t733, t912, t1239, t1270, t4802, and t6969) and isolates gathered from milk or pork. The porcine isolates were assigned to t034, t208, t337, t524, t899, t1939, t2922, t2971, t4475, and t7006, and the bovine isolates belonged to t267, t524, t529, t1403, t2953, t7007, t7008, and t7013. Comparison of microarray profiles revealed similar virulence gene patterns for isolates collected from the same host (pigs or cattle) but few similarities between SFP isolate profiles and the profiles of isolates obtained from bovine mastitis milk and pig carcasses. Although only some bovine and porcine isolates possessed the β-lactamase gene blaZ (milk, 24%; pork, 28%), significantly higher numbers of SFP isolates contained blaZ (90%). Investigations of these isolates provided no evidence that pork or bovine mastitis milk represent common sources of SFP.

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Li, Yongru, Hongwei Su, and Yajia Lan. "Simultaneous Detection of Yersinia Enterocolitica and Listeria Monocytogenes in Foodstuffs by Capillary Electrophoresis and Microchip Capillary Electrophoresis Laser-Induced Fluorescence Detector." Journal of AOAC INTERNATIONAL 101, no. 6 (November 1, 2018): 1833–38. http://dx.doi.org/10.5740/jaoacint.17-0507.

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Abstract Background: Food safety is one of the most important public health problems in the world, and pathogenic bacterium is a major factor causing serious foodborne diseases. Objective: Two methods of duplex PCR combined with capillary electrophoresis laser-induced fluorescence detector (CE-LIF) and microchip capillary electrophoresis laser-induced fluorescence detector (MCE-LIF) have been developed for the simultaneous detection of Yersinia Enterocolitica and Listeria Monocytogenes in various foods. The specific conservative sequences of these two bacteria were amplified. Methods: After labelled with nucleic acid dye SYBR Gold and SYBR Orange, the PCR products were analyzed by CE-LIF and MCE-LIF, respectively. Under the optimal conditions, the detection of PCR products of the target bacteria was achieved in less than 15 min by CE-LIF and within 6 min by MCE-LIF. Results: The alignment analysis demonstrated that the PCR products had good agreement with the sequences published in GenBank. The CE-LIF method could detect 10 CFU/mL Y. enterocolitica and L. monocytogenes, and the MCE-LIF method could detect 100 CFU/mL Y. enterocolitica and L. monocytogenes. The intraday precisions of migration time and peak area of DNA markers and PCR products were in the range of 1.13 to 1.18% and 1.60 to 6.29%, respectively, for CE-LIF and 1.18 to 1.48% and 2.85 to 4.06%, respectively, for MCE-LIF. Conclusions: The proposed methods could be applied to target bacterial detection infood samples rapidly, sensitively, and specifically. Highlights: Two new methods based on CE and MCE have been developed for the simultaneous detection of Y. enterocolitica and L. monocytogenes in foodstuffs, and they can detect the bacteria directly without any enrichment because of their high sensitivity.

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Sithole, Viwe, Daniel Gyamfi Amoako, Akebe Luther King Abia, Keith Perrett, Linda A. Bester, and Sabiha Y. Essack. "Occurrence, Antimicrobial Resistance, and Molecular Characterization of Campylobacter spp. in Intensive Pig Production in South Africa." Pathogens 10, no. 4 (April 7, 2021): 439. http://dx.doi.org/10.3390/pathogens10040439.

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Campylobacter spp. are among the leading foodborne pathogens, causing campylobacteriosis, a zoonotic infection that results in bacterial gastroenteritis and diarrheal disease in animals and humans. This study investigated the molecular epidemiology of antibiotic-resistant Campylobacter spp. isolated across the farm-to-fork-continuum in an intensive pig production system in South Africa. Following ethical approval, samples were collected over sixteen weeks from selected critical points (farm, transport, abattoir, and retail) using a farm-to-fork sampling approach according to WHO-AGISAR guidelines. Overall, 520 samples were investigated for the presence of Campylobacter spp., which were putatively identified using selective media with identity and speciation confirmed by polymerase chain reaction (PCR) of specific genes. Resistance profiles were ascertained by the Kirby–Bauer disk diffusion method. Antibiotic resistance and virulence genes were identified using PCR and DNA sequencing. Clonal relatedness was determined using ERIC-PCR. Altogether, 378/520 (72.7%) samples were positive for Campylobacter spp., with Campylobacter coli being the predominant species (73.3%), followed by Campylobacter jejuni (17.7%); 8.9% of the isolates were classified as “other spp”. Relatively high resistance was observed in C. coli and C. jejuni to erythromycin (89% and 99%), streptomycin (87% and 93%), tetracycline (82% and 96%), ampicillin (69% and 85%), and ciprofloxacin (53% and 67%), respectively. Multidrug resistance (MDR) was noted in 330 of the 378 (87.3%) isolates. The antibiotic resistance genes observed were tetO (74.6%), blaOXA-61 (2.9%), and cmeB (11.1%), accounting for the resistance to tetracycline and ampicillin. The membrane efflux pump (cmeB), conferring resistance to multiple antibiotics, was also detected in most resistant isolates. Chromosomal mutations in gyrA (Thr-86-Ile) and 23S rRNA (A2075G and A2074C) genes, conferring quinolone and erythromycin resistance, respectively, were also found. Of the virulence genes tested, ciaB, dnaJ, pldA, cdtA, cdtB, cdtC, and cadF were detected in 48.6%, 61.1%, 17.4%, 67.4%, 19.3%, 51%, and 5% of all Campylobacter isolates, respectively. Clonal analysis revealed that isolates along the continuum were highly diverse, with isolates from the same sampling points belonging to the same major ERIC-types. The study showed relatively high resistance to antibiotics commonly used in intensive pig production in South Africa with some evidence, albeit minimal, of transmission across the farm-to-fork continuum. This, together with the virulence profiles present in Campylobacter spp., presents a challenge to food safety and a potential risk to human health, necessitating routine surveillance, antibiotic stewardship, and comprehensive biosecurity in intensive pig production.

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Marlina. "MULTIDRUG RESISTANCE (MDR) OF V. Parahaemolyticus." Jurnal Riset Kimia 2, no. 2 (February 12, 2015): 112. http://dx.doi.org/10.25077/jrk.v2i2.150.

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Vol. 2, No. 2 ABSTRACT A total of 97 V. parahaemolyticus isolate from Padang were examined for their resistance to 15 antibiotics. V. parahaemolyticus isolated behaved as resistant to sulfamethoxazole (100%), rifampin (95%) and tetracycline (75%) and sensitive to norfloxacin (96%). Ampicillin still sensitive for V. parahaemolyticus isolated from human stools. All of isolates were sensitive to namely chloramphenicol and floroquinolones (ciprofloxacin and norfloxacin agents). RAPD-PCR profiling with three primers (OPAR3, OPAR4 and OPAR8) produced four major clusters (R1, R2, R3 and R4), 7 minor clusters (I, II, III, IV, V, VI and VII) and three single isolates. Keywords: V. parahaemolyticus, MDR, RAPD 1. D. Ottaviani, I. Bacchiocchi, L. Masini, F. Leoni, A. Carraturo, M. Giammarioli, and G. Sbaraglia, Antimicrobial susceptibility of potentially halophilic vibrios isolated from seafood, International Journal of Antimicrobial Agents 18: 135-140, (2001).2. A. Cespedes, and E. Larson, Knowledge, attitude and practices regarding antibiotic use among Latinos in the United States: Review and Recommendations, American Journal of Infection Control 34: 495-502, (2006).3. M. Lesmana, D. Subekti, C.H. Simanjuntak, P. Tjaniadi, J. R. Campbell, and B. A. Ofoyo, Vibrio parahaemolyticus associated with cholera-like diarrhea among patients in North Jakarta, Indonesia, Diagnostic Microbiology and Infectious Disease, 39: 71-75, (2001).4. S. Lu, B. Liu, B. Zhou, And R. E. Levin, Incidence and Enumeration of Vibrio parahaemolyticus in Shellfish from two retail Sources and the Genetic Diversity of isolates as Determined by RAPD-PCR Analysis, Food Biotechnology, 20: 193-209, (2006).5. M. Nishibuchi, Vibrio parahaemolyticus. In International handbook of foodborne pathogens, ed. M.D. Milliots and J. W. Bier, United States: Marcel Dekker, Inc. P, 2004, 237-252.6. L. Poirel, M. R. Martinez, H. Mammeri, A. Liard, and P. Nordmann, Origin of Plasmid-Mediated Quinolone Resistance Determinant QnrA, Antimicrobial Agents and Chemotherapy, 49: 3523-3525, (2005).7. S. Radu, N. Elhadi, Z. Hassan, G. Rusul, S. Lihan, N. Fifadara, Yuherman and E. Purwati, Characterization of Vibrio vulnificus isolated from cockles (Anadara granosa): antimicrobial resistance, plasmid profiles and random amplification of polymorphic DNA analysis, FEMS Microbiology Letters, 165: 139–143, (1998).8. S. Radu, N. Ahmad, F. H. Ling, and A. Reezal, Prevalence and resistance to antibiotics for Aeromonas species from retail fish in Malaysia, International of Journal Food Microbiology, 81: 261–266, (2003).9. B. Sarkar, N. R. Chowdhury, G. B. Nair, M. Nishibuchi, S. Yamasaki, Y. Takeda, S. K. Gupta, S. K. Bhattacharya, and Ramamurthy, Molecular characterization of Vibrio parahaemolyticus of similar serovars isolated from sewage and clinical cases of diarrhea in Calcutta, India, World Journal of Microbiology and Biotechnology, 19: 771-776, (2003). 10. S. Schwarz, and E. Chaslus-Dancla, Use of antimicrobials in veterinary medicine and mechanisms of resistance, Veterinary Residue, 32: 201–225, (2001).11. H. Sörum, and T.M. L’Abèe-Lund,. Antibiotic resistance in food-related bacteria – a result of interfering with the global web of bacterial genetics, International Journal of Food Microbiology, 78: 43–56, (2002).12. P. Tjaniadi, M. Lesmana, D. Subekti, N. Machpud, S. Komalarini, W. Santoso, C. H. Simanjuntak, N. Punjabi, J. R. Campbell, W. K. Alexander, H. J. Beecham, A. L. Corwin, and B. A. Oyofo, Antimicrobial Resistance of Bacterial Pathogens Associated with Diarrheal Patients in Indonesia, American Journal of Tropical Medicine and Hygiene, 68: 666-670, (2003).13. X. Zhao, and D. Drlica, Restricting the Selection of Antibiotic-Resistant Mutants: A General Strategy Derived from Fluoroquinolone Studies, Clinical Infectious Diseases, 33: S147-S156, (2001).

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Andrade Júnior, Francisco Patricio de, Brenda Tamires de Medeiros Lima, Brencarla de Medeiros Lima, Laísa Vilar Cordeiro, Vanessa Santos de Arruda Barbosa, and Edeltrudes de Oliveira Lima. "Contamination of chickens by Salmonella spp., in Brazil: an important public health problem." ARCHIVES OF HEALTH INVESTIGATION 9, no. 5 (April 20, 2020): 474–78. http://dx.doi.org/10.21270/archi.v9i5.4793.

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Introduction: Bacteria of the genus Salmonella are important pathogens involved in the contamination of various foods, such as chickens, and may cause food poisoning. Aim: The present study aimed to review the literature on the prevalence of chickens contaminated with Salmonella spp., which are commercializated in different Brazilian states. Material and methods: This was a literary review. The absolute frequency and the total percentage of contaminated samples was calculated and the Qui-square statistical test was applied, considering statistically significant p <0.05. Results: 616 publications were retrieved, but only 10 articles were included to compose the results. The cataloged studies were carried out in 14 different brazilian states, and it was observed that of 5,030 chicken samples analyzed, the mean prevalence of samples contaminated with Salmonellawas 7,3% (n= 365). In addition, the prevalence of samples in the different studies ranged from 2.5% to 44.6%. The most prevalent serotype was S. Enteritidis (28,7%) and a statistically significant association between the type of raw material for commercialization and the result of the chicken samples microbiological analysis was observed (p<0.001), where the carcasses represented 90.1% of the contaminated samples. Conclusion: Thus, the data presented in this study can serve as subsidy for the development of necessary, political or legislative, measures that allow a better control of commercialized chickens in Brazil.Descriptors: Salmonella; Foodborne Diseases; Epidemiology.ReferencesSouza GC, Gonsalves HRO, Gonsalves HEO, Coêlho JLS. Característica microbiológica da carne de frango. ACSA. 2014;10(1):12-17.Pinto LAM, Pinto MM, Bovo J, Mateus GAP, Tavres FO, Baptista ATA, et al. Aspectos ambientais do abate de aves: uma revisão. Rev Uningá. 2018;22(3):44-50.Oliveira ME, Oliveira RLZ, Souza MFLZ, Harada ES, Tech ARB. Desenvolvimento de sensores para monitoramento de ambiente aviário com ênfase em controle térmico. Int J Agric & Biol Eng. 2018;12(3):234-40.Cintra APR, Andrade MCG, Lazarini MM, Assis DCS, Silva GR, Menezes LDM, et al. Influence of cutting room temperature on the microbiological quality of chicken breast meat. Arq Bras Med Vet Zootc. 2016;68(3):814-20.Rückert DAS, Pinto PSA, Santos BM, Moreira MAS, Rodrigues ACA. Pontos críticos de controle de Salmonella spp. no abate de frangos. Arq Bras Med Vet Zootec. 2009;61(2):326-30.Oliveira AP, Sola MC, Feistel JC, Moreira NM, Oliveira JJ. 2013. Salmonella enterica: genes de virulência e ilhas de patogenicidade. Enciclopedia Biosfera. 2013;9(16):1947-72.Brasil. Ministério da Saúde [homepage na internet]. Surtos de doenças transmitidas por alimentos no Brasil [acesso em 15 jul 2018]. Disponível em: http://portalarquivos2.saude.gov.br/images/pdf/2018/julho/02/Apresentacao-Surtos-DTA-Junho-2018.pdf.Borsoi A, Moraes HLS, Salle CTP, Nascimento VP. Número mais provável de Salmonella isoladas de carcaças de frango resfriadas. Ciênc Rural. 2010;40(11):2338-42.Cardoso KF, Rall VLM, Mendes AA, Paz ICLA, Komiyama CM. Pesquisa de salmonella e coliformes termotolerantes em cortes de frango obtidos no comércio de Botucatu/SP. Hig Aliment. 2009;23(176/179):165-68.Cunha-Neto AD, Carvalho LA, Carvalho RCT, Dos Prazeres Rodrigues D, Mano SB, Figueiredo EES, Conte-Junior CA. Salmonella isolated from chicken carcasses from a slaughterhouse in the state of Mato Grosso, Brazil: antibiotic resistance profile, serotyping, and characterization by repetitive sequence-based PCR system. Poult Sci. 2018;97(4):1373-81. Duarte DAM, Ribeiro AR, Vasconcelos AMM, Santos SB, Silva JVD, Andrade PLA, et al. Occurrence of Salmonella spp. in broiler chicken carcasses and their susceptibility to antimicrobial agents. Braz J Microbiol. 2009;40(3):569-73.Medeiros MA, Oliveira DC, Rodrigues DP, Freitas DR. Prevalence and antimicrobial resistance of Salmonella in chicken carcasses at retail in 15 Brazilian cities. Rev Panam Salud Publica. 2011;30(6):555-60.Menezes LDM, Lima AL, Pena EC, Silva GR, Klein RWT, Silva CA, et al. Caracterização microbiológica de carcaças de frangos de corte produzidas no estado de Minas Gerais. Arq Bras Med Vet Zootec. 2018;70(2):623-27.Moreira GN, Rezende CSM, Carvalho RN, Mesquita SQP, Oliveira AN, Arruda MLT. Ocorrência de Salmonella sp. em carcaças de frangos abatidose comercializados em municípios do estado de Goiás. Rev Inst Adolfo Lutz. 2008;67(2):126-30.Possebon FS, Costa LFZP, Yamatogi RS, Rodrigues MV, Sudano MJ, Pinto JPAN. A refrigeração no diagnóstico de Salmonella spp. utilizando o método microbiológico tradicional e reação em cadeia da polimerase em carcaças de frango. Ciênc Rural. 2012;42(1):131-35.Tessari ENC, Cardoso ALSP, Kanashiro AMI, Stoppa GFZ, Luciano RL, Castro AGM. Ocorrência de Salmonella spp. em carcaças de frangos industrialmente processadas procedentes de explorações industriais do Estado de São Paulo, Brasil. Cienc Rural, 2008; 38(9):2557-60.Yamatogi RS, Galvão JA, Baldini ED, Souza Júnior LCT, Rodrigues MV, Pinto JPAN. Avaliação da unidade analítica na detecção de Salmonella spp. em frangos a varejo. Rev Inst Adolfo Lutz. 2011;70(4):637-40.Sharma J, Kumar D, Hussain S, Pathak A, Shukla M, Kumar VP, et al. Prevalence, antimicrobial resistence and virulence genes characterization of montyphoidal Salmonella isolated from retail chicken meat shops in Northern India. Food Control. 2019;102:104-11.Harb A, Babib I, Mezal EH, Kareem HS, Laird T, O’dea M, et al. Ocurrence, antimicrobial resistence and whole-genome sequencing analysis of Salmonella isolates from chicken carcasses imported into Iraq from four different countries. Int J Food Microbiol. 2018;284:84-90.Zwe YH, Yentang VC, Aung KT, Gutiérrez RA, Ng LC, Yuk HG. Prevalence, sequence types, antibiotic resistance and, gyrA mutations of Salmonella isolated from retail fresh chicken meat in Singapore. Food Control. 2018;90:233-40.Goni AM, Effarizah ME, Rusul G. Prevalence, antimicrobial resistance, resistance genes and class 1 integrons of Salmonella serovars in leafy vegetables, chicken carcasses and related processing environments in Malaysian fresh food markets. Food Control. 2018;91:170-80.Zhu J, Wang Y, Song X, Cui S, Xu H, Yang B, et al. Prevalence and quantification of Salmonella contamination in raw chicken carcasses at the retail in China. Food Control. 2014;44:198-202.Kramarenko T, Nurmoja I, Karssin A, Meremae K., Horman A, Roasto M. The prevalence and serovar diversity of Salmonella in various food products in Estonia. Food Control. 2014;42:43-7.Smadi H, Sargeant JM, Shannon HS, Raina P. Growth and inactivation of Salmonella at low refrigerated storage temperatures and thermal inactivation on raw chicken meat and laboratory media: Mixed effect meta-analysis. Journal of Epidemiology and global Health. 2012;2(4):165-79.Cardoso ALSP, Tessari ENC. Salmonella enteritidis em aves e na saúde pública: revisão da literatura. R cient eletr Med Vet. 2013;11(21).Realpe-Delgado ME, Muñoz-Delgado AB, Donado-Godoy P, Rey-Ramírez LM, Díaz-Guevara PL, Arévalo-Mayorga SA. Epidemiología de Salmonella spp., Listeria monocytogenes y Campylobacter spp., en la cadena productiva avícula. Iatreia. 2016;22(4):397-406.Shinohara NKS, Barros VB, Jimenez SMC, Machado ECL, Dutra RAF, Lima Filho JL. Salmonella spp., importante agente patogênico veiculado em alimentos. Ciênc. sáude coletiva. 2008;13(5):1675-83.Lv S, Si W, Yu S, Li Z, Wang X, Chen L, Zhang W, Liu S. Characteristics of invasion-reduced hilA gene mutant of Salmonella Enteritidis in vitro and in vivo. Res Vet Sci. 2015;101:63-8.Feasey NA, Hadfield J, Keddy KH, Dallman TJ, Jacobs J, Deng X, et al. Distinct Salmonella Enteritidis lineages associated with enterocolitis in high-income settings and invasive disease in low-income settings. Nat Genet. 2014;48(10):1211-17.

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Muriuki, Susan W., Michael S. Rengan, and Nancy L. M. Budambula. "Prokaryotic diversity and potentially pathogenic bacteria in vended foods and environmental samples." Annals of Microbiology 71, no. 1 (July 12, 2021). http://dx.doi.org/10.1186/s13213-021-01640-w.

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Abstract Purpose Ready-to-eat fast food vending outlets provide a cheap and readily available food. Foodborne diseases have been previously reported in Embu, Kenya, but data on the prokaryotic metagenome in vended foods is scanty. This study aimed to determine the prokaryotic diversity in fruits, vegetable salad, African sausage, chips (potato fries), fried fish, roasted beef (meat), smokies, samosa, soil, and water collected from food vendors and the surrounding environment in Embu Town and Kangaru Market. Methods The study used 454 pyrosequencing, Illumina high-throughput sequencing of 16S rRNA gene in the analysis of total community DNA extracted from samples using the phenol-chloroform method. The 16S rRNA gene variable region (V4-V7) of the extracted DNA was amplified and library construction performed. Sequence analysis was done using QIIME2. Hierarchical clustering of samples, diversity indices, rarefaction curves, and Venn diagrams were generated using the R programming language in R software version 3.6.3. Results Bacterial operational taxonomic units (OUTs) were distributed in Proteobacteria (52.81%), Firmicutes (31.16%), and Lentisphaerae (0.001%). The OTUs among archaea were Candidatus Nitrososphaera (63.56%) and Nitrososphaera spp. (8.77%). Brucella spp. and Bacillus cereus associated with foodborne diseases were detected. Potential pathogens, Rickettsia spp. in risk group 2 and Brucella spp. in risk group 3, were detected. Uncultured Candidatus Koribacter and Candidatus Solibacter were also detected in the food samples. There was a significant difference in the microbial community structure among the sample types (P<0.1). Conclusion The results demonstrated the presence of some prokaryotes that are associated with food spoilage or foodborne diseases in vended foods and environmental samples. This study also detected uncultured prokaryotes. The presence of potential pathogens calls for stringent hygiene measures in food vending operations.

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Lass, Anna, Beata Szostakowska, Przemyslaw Myjak, and Krzysztof Korzeniewski. "Detection of Echinococcus multilocularis DNA in fruit, vegetable, and mushroom samples collected in the non-endemic territory of the Pomerania province and comparison of the results with data from rural areas of the neighbouring highly endemic Warmia-Masuria province, Poland." Acta Parasitologica 62, no. 2 (January 1, 2017). http://dx.doi.org/10.1515/ap-2017-0053.

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Abstractis a tapeworm that may cause alveolar echinococcosis (AE), one of the most dangerous parasitic zoonoses. As in the case of some foodborne diseases, unwashed fruits and vegetables contaminated with eggs of

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Zhang, Mimi, Jinfeng Liu, Zhiqiang Shen, Yongxin Liu, Yang Song, Yu Liang, Zhende Li, Lingmei Nie, Yanjun Fang, and Youquan Zhao. "A newly developed paper embedded microchip based on LAMP for rapid multiple detections of foodborne pathogens." BMC Microbiology 21, no. 1 (June 28, 2021). http://dx.doi.org/10.1186/s12866-021-02223-0.

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Abstract Background Microfluidic chip detection technology is considered a potent tool for many bioanalytic applications. Rapid detection of foodborne pathogens in the early stages is imperative to prevent the outbreak of foodborne diseases, known as a severe threat to human health. Conventional bacterial culture methods for detecting foodborne pathogens are time-consuming, laborious, and lacking in pathogen diagnosis. To overcome this problem, we have created an embedded paper-based microchip based on isothermal loop amplification (LAMP), which can rapidly and sensitively detect foodborne pathogens. Results We embed paper impregnated with LAMP reagent and specific primers in multiple reaction chambers of the microchip. The solution containing the target pathogen was injected into the center chamber and uniformly distributed into the reaction chamber by centrifugal force. The purified DNA of Escherichia coli O157:H7, Salmonella spp., Staphylococcus aureus, and Vibrio parahaemolyticus has been successfully amplified and directly detected on the microchip. The E. coli O157:H7 DNA was identified as low as 0.0134 ng μL− 1. Besides, the potential of this microchip in point-of-care testing was further tested by combining the on-chip sample purification module and using milk spiked with Salmonella spp.. The pyrolyzed milk sample was filtered through a polydopamine-coated paper embedded in the inside of the sample chamber. It was transported to the reaction chamber by centrifugal force for LAMP amplification. Then direct chip detection was performed in the reaction chamber embedded with calcein-soaked paper. The detection limit of Salmonella spp. in the sample measured by the microchip was approximately 12 CFU mL− 1. Conclusion The paper embedded LAMP microchip offers inexpensive, user-friendly, and highly selective pathogen detection capabilities. It is expected to have great potential as a quick, efficient, and cost-effective solution for future foodborne pathogen detection.

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Pettengill, James B., Jennifer Beal, Maria Balkey, Marc Allard, Hugh Rand, and Ruth Timme. "Interpretative Labor and the Bane of Nonstandardized Metadata in Public Health Surveillance and Food Safety." Clinical Infectious Diseases, July 8, 2021. http://dx.doi.org/10.1093/cid/ciab615.

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Abstract Open-source DNA sequence databases have long been touted as beneficial to public health, including the facilitation of earlier detection and response to infectious disease outbreaks. Of critical importance to harnessing these benefits is the metadata that describe general and other domain-specific attributes (eg, collection location, isolate type) of a sample. Unlike the sequence data, metadata are often incomplete and lack adherence to an international standard. Here, we describe the problem posed by such variable and incomplete metadata in terms of interpretative labor costs (the time and energy necessary to make sense of the signal in the genetic data) and the impact such metadata have on foodborne outbreak detection and response. Improving the quality of sequence-associated metadata would allow for earlier detection of emerging food safety hazards and allow faster response to foodborne outbreaks.

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Huang, Andrew D., Chengwei Luo, Angela Pena-Gonzalez, Michael R. Weigand, Cheryl L. Tarr, and Konstantinos T. Konstantinidis. "Metagenomics of Two Severe Foodborne Outbreaks Provides Diagnostic Signatures and Signs of Coinfection Not Attainable by Traditional Methods." Applied and Environmental Microbiology 83, no. 3 (November 23, 2016). http://dx.doi.org/10.1128/aem.02577-16.

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ABSTRACT Diagnostic testing for foodborne pathogens relies on culture-based techniques that are not rapid enough for real-time disease surveillance and do not give a quantitative picture of pathogen abundance or the response of the natural microbiome. Powerful sequence-based culture-independent approaches, such as shotgun metagenomics, could sidestep these limitations and potentially reveal a pathogen-specific signature on the microbiome that would have implications not only for diagnostics but also for better understanding disease progression and pathogen ecology. However, metagenomics have not yet been validated for foodborne pathogen detection. Toward closing these gaps, we applied shotgun metagenomics to stool samples collected from two geographically isolated (Alabama and Colorado) foodborne outbreaks, where the etiologic agents were identified by culture-dependent methods as distinct strains of Salmonella enterica subsp. enterica serovar Heidelberg. Metagenomic investigations were consistent with the culture-based findings and revealed, in addition, the in situ abundance and level of intrapopulation diversity of the pathogen, the possibility of coinfections with Staphylococcus aureus, overgrowth of commensal Escherichia coli, and significant shifts in the gut microbiome during infection relative to reference healthy samples. Additionally, we designed our bioinformatics pipeline to deal with several challenges associated with the analysis of clinical samples, such as the high frequency of coeluting human DNA sequences and assessment of the virulence potential of pathogens. Comparisons of these results to those of other studies revealed that in several, but not all, cases of diarrheal outbreaks, the disease and healthy states of the gut microbial community might be distinguishable, opening new possibilities for diagnostics. IMPORTANCE Diagnostic testing for enteric pathogens has relied for decades on culture-based techniques, but a total of 38.4 million cases of foodborne illness per year cannot be attributed to specific causes. This study describes new culture-independent metagenomic approaches and the associated bioinformatics pipeline to detect and type the causative agents of microbial disease with unprecedented accuracy, opening new possibilities for the future development of health technologies and diagnostics. Our tools and approaches should be applicable to other microbial diseases in addition to foodborne diarrhea.

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Zhao, Liwei, Jianchang Wang, Xiao Xia Sun, Jinfeng Wang, Zhimin Chen, Xiangdong Xu, Mengyuan Dong, et al. "Development and Evaluation of the Rapid and Sensitive RPA Assays for Specific Detection of Salmonella spp. in Food Samples." Frontiers in Cellular and Infection Microbiology 11 (February 25, 2021). http://dx.doi.org/10.3389/fcimb.2021.631921.

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Salmonella spp. is among the main foodborne pathogens which cause serious foodborne diseases. An isothermal real-time recombinase polymerase amplification (RPA) and lateral flow strip detection (LFS RPA) were used to detect Salmonella spp. targeting the conserved sequence of invasion protein A (invA). The Real-time RPA was performed in a portable florescence scanner at 39°C for 20 min. The LFS RPA was performed in an incubator block at 39°C for 15 min, under the same condition that the amplifications could be inspected by the naked eyes on the LFS within 5 min. The detection limit of Salmonella spp. DNA using real-time RPA was 1.1 × 101 fg, which was the same with real-time PCR but 10 times higher than that of LFS RPA assay. Moreover, the practicality of discovering Salmonella spp. was validated with artificially contaminated lamb, chicken, and broccoli samples. The analyzing time dropped from 60 min to proximately 5–12 min on the basis of the real-time and LFS RPA assays compared with the real-time PCR assay. Real-time and LFS RPA assays’ results were equally reliable. There was no cross-reactivity with other pathogens in both assays. In addition, the assays had good stability. All of these helped to show that the developed RPA assays were simple, rapid, sensitive, credible, and could be a potential point-of-need (PON) test required mere resources.

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Buuck, S., K. Smith, R. C. Fowler, E. Cebelinski, V. Lappi, D. Boxrud, and C. Medus. "Epidemiology of Enterotoxigenic Escherichia coli infection in Minnesota, 2016–2017." Epidemiology and Infection 148 (2020). http://dx.doi.org/10.1017/s0950268820001934.

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Abstract Enterotoxigenic Escherichia coli (ETEC) is a well-established cause of traveller's diarrhoea and occasional domestic foodborne illness outbreaks in the USA. Although ETEC are not detected by conventional stool culture methods used in clinical laboratories, syndromic culture-independent diagnostic tests (CIDTs) capable of detecting ETEC have become increasingly prevalent in the last decade. This study describes the epidemiology of ETEC infections reported to the Minnesota Department of Health (MDH) during 2016–2017. ETEC-positive stool specimens were submitted to MDH to confirm the presence of ETEC DNA by polymerase chain reaction (PCR). Cases were interviewed to ascertain illness and exposures. Contemporaneous Salmonella cases were used as a comparison group in a case-case comparison analysis of risk factors. Of 222 ETEC-positive specimens received by MDH, 108 (49%) were concordant by PCR. ETEC was the sixth most frequently reported bacterial enteric pathogen among a subset of CIDT-positive specimens. Sixty-nine (64%) laboratory-confirmed cases had an additional pathogen codetected with ETEC, including enteroaggregative E. coli (n = 40) and enteropathogenic E. coli (n = 39). Although travel is a risk factor for ETEC infection, only 43% of cases travelled internationally, providing evidence for ETEC as an underestimated source of domestically acquired enteric illness in the USA.

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Huang, Yu, Dan Gu, Han Xue, Jinyan Yu, Yuanyue Tang, Jinlin Huang, Yunzeng Zhang, and Xinan Jiao. "Rapid and Accurate Campylobacter jejuni Detection With CRISPR-Cas12b Based on Newly Identified Campylobacter jejuni-Specific and -Conserved Genomic Signatures." Frontiers in Microbiology 12 (April 27, 2021). http://dx.doi.org/10.3389/fmicb.2021.649010.

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Campylobacter jejuni is among the most prevalent foodborne zoonotic pathogens leading to diarrheal diseases. In this study, we developed a CRISPR-Cas12b-based system to rapidly and accurately detect C. jejuni contamination. Identification of C. jejuni-specific and -conserved genomic signatures is a fundamental step in development of the detection system. By comparing C. jejuni genome sequences with those of the closely related Campylobacter coli, followed by comprehensive online BLAST searches, a 20-bp C. jejuni-conserved (identical in 1024 out of 1037 analyzed C. jejuni genome sequences) and -specific (no identical sequence detected in non-C. jejuni strains) sequence was identified and the system was then assembled. In further experiments, strong green fluorescence was observed only when C. jejuni DNA was present in the system, highlighting the specificity of this system. The assay, with a sample-to-answer time of ∼40 min, positively detected chicken samples that were contaminated with a dose of approximately 10 CFU C. jejuni per gram of chicken, which was >10 times more sensitive than the traditional Campylobacter isolation method, suggesting that this method shows promise for onsite C. jejuni detection. This study provides an example of bioinformatics-guided CRISPR-Cas12b-based detection system development for rapid and accurate onsite pathogen detection.

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Morrison, Holly A., David Lowe, Jennifer R. Robbins, and Anna I. Bakardjiev. "In VivoVirulence Characterization of Pregnancy-AssociatedListeria monocytogenesInfections." Infection and Immunity 86, no. 11 (August 13, 2018). http://dx.doi.org/10.1128/iai.00397-18.

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ABSTRACTListeria monocytogenesis a foodborne pathogen that infects the placenta and can cause pregnancy complications. Listeriosis usually occurs as a sporadic infection, but large outbreaks are also reported. Virulence from clinical isolates is rarely analyzed due to the large number of animals required, but this knowledge could help guide the response to an outbreak. We implemented a DNA barcode system using signature tags that allowed us to efficiently assay variations in virulence across a large number of isolates. We tested 77 signature-tagged clones of clinicalL. monocytogenesstrains from 72 infected human placentas and 5 immunocompromised patients, all of which were isolated since 2000. These strains were tested for virulence in a modified competition assay in comparison to that of the laboratory strain 10403S. We used twoin vivomodels of listeriosis: the nonpregnant mouse and the pregnant guinea pig. Strains that were frequently found at a high abundance within infected organs were considered hypervirulent, while strains frequently found at a low abundance were considered hypovirulent. Virulence split relatively evenly among hypovirulent strains, hypervirulent strains, and strains as virulent as 10403S. The laboratory strain was found to have an intermediate virulence phenotype, supporting its suitability for use in pathogenesis studies. Further, we found that splenic virulence and placental virulence are closely linked in both the guinea pig and mouse models. This suggests that outbreak and sporadic pregnancy-associatedL. monocytogenesstrains are not generally more virulent than lab reference strains. However, some strains did show consistent and reproducible virulence differences, suggesting that their further study may reveal deeper insights into the biological underpinnings of listeriosis.

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48

Hald, T. "Using novel methodologies to support burden of disease estimates." European Journal of Public Health 30, Supplement_5 (September 1, 2020). http://dx.doi.org/10.1093/eurpub/ckaa165.951.

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Abstract A challenge to estimating burden of diarrheal diseases, particularly in LMICs, where laboratory capacity and surveillance systems are limited, is obtaining valid estimates of etiology proportions of cases. A commonly used method is systematic review of studies reporting pathogen isolation in diarrhea cases. However, studies often differ in design, source population, timeframe, and pathogens included, hampering extrapolation to the target population. In a study co-funded by the Bill and Melinda Gates Foundation and the UK Department for International Development, we explore a novel approach for estimating diarrhea etiology proportions in urban and rural populations in four African countries. We analyse sewage samples using short-read next-generation sequencing (NGS) to determine abundance of genes that can be mapped to specific bacterial genera, providing an estimate of the relative abundance of specific pathogens in each sample. In parallel to collecting sewage samples, a questionnaire-based population survey will estimate diarrheal incidence. By combining results, pathogen-specific incidence will be estimated and compared with incidence estimates from the traditional approach. The application NGS to human sewage has great potential for surveillance of foodborne infections, particularly in resource-poor settings where laboratory capacity for bacterial isolation is limited. First, NGS is a one method takes all approach, as it is based on detection of RNA/DNA, a language common across pathogens. Second, it is culture independent, allowing for real-time data generation and standardized sharing. Finally, few samples are needed to survey large populations for several pathogens at the same time. Thus, surveillance based on NGS of sewage may prove to be an indirect measure of incidence. Although it will not provide an estimate for the true incidence in the population, it will increase our understanding of the burden and as such be a proxy and novel way of ranking diseases.

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Jafari, Erfaneh, Mana Oloomi, and Saeid Bouzari. "Characterization of antimicrobial susceptibility, extended-spectrum β-lactamase genes and phylogenetic groups of Shigatoxin producing Escherichia coli isolated from patients with diarrhea in Iran." Annals of Clinical Microbiology and Antimicrobials 20, no. 1 (April 15, 2021). http://dx.doi.org/10.1186/s12941-021-00430-1.

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Abstract Background Shiga toxin‐producing Escherichia coli (STEC) are among common foodborne bacterial pathogens and healthy livestock are the main source of this bacterium. Severe diseases attribute to two types of cytotoxin Stx1 and Stx2, which are also called Shiga toxin (Stx). Infection of humans with STEC may result in Acute diarrhea with or without bleeding, hemorrhagic colitis (HC) and the hemolytic uremic syndrome (HUS). As antibiotic resistance is increasingly being reported among STEC isolates obtained from livestock and patients worldwide, in this study the pattern of antibiotic resistance in clinical isolates was determined. Methods Stool samples were collected from patients with diarrhea. All samples were cultured and identified by biochemical and molecular tests. Antimicrobial susceptibility test and assessment of extended-spectrum β-lactamase (ESBL)-related genes were conducted. Moreover, phylogenetic groups were analyzed using quadruplex PCR, and DNA analysis assessed multi-locus sequence types (MLST). Results Out of 340 E. coli samples, 174 were identified as STEC by PCR. Antimicrobial susceptibility test results showed that, 99.4%, 96% and 93.1% of isolates were susceptible to imipenem/ertapenem, piperacillin–tazobactam and amikacin, respectively. The highest resistance was towards ampicillin (68.4%), followed by trimethoprim–sulfamethoxazole (59.8%), and tetracycline (57.5%). A total of 106 (60.9%) isolates were multidrug resistance (MDR) and 40.8% of isolates were determined to be extended spectrum β-lactamase producers. In 94.4% of isolates, genes responsible for ESBL production could be detected, and blaTEM was the most prevalent, followed by blaCTX-M9. Furthermore, phylogenetic grouping revealed that majority of STEC strains belonged to Group C, followed by Groups E, B2 and A. MLST unveiled diverse ST types. Conclusion A periodical surveillance studies and thorough understanding of antibiotic resistant profiles in STEC isolates could help select effective antibiotic treatment for patients and develop strategies to effectively manage food contamination and human infections.

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Ellermann, Melissa, Angel G. Jimenez, Reed Pifer, Nestor Ruiz, and Vanessa Sperandio. "The Canonical Long-Chain Fatty Acid Sensing Machinery Processes Arachidonic Acid To Inhibit Virulence in Enterohemorrhagic Escherichia coli." mBio 12, no. 1 (January 19, 2021). http://dx.doi.org/10.1128/mbio.03247-20.

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ABSTRACT The mammalian gastrointestinal tract is a complex biochemical organ that generates a diverse milieu of host- and microbe-derived metabolites. In this environment, bacterial pathogens sense and respond to specific stimuli, which are integrated into the regulation of their virulence programs. Previously, we identified the transcription factor FadR, a long-chain fatty acid (LCFA) acyl coenzyme A (acyl-CoA) sensor, as a novel virulence regulator in the human foodborne pathogen enterohemorrhagic Escherichia coli (EHEC). Here, we demonstrate that exogenous LCFAs directly inhibit the locus of enterocyte effacement (LEE) pathogenicity island in EHEC through sensing by FadR. Moreover, in addition to LCFAs that are 18 carbons in length or shorter, we introduce host-derived arachidonic acid (C20:4) as an additional LCFA that is recognized by the FadR system in EHEC. We show that arachidonic acid is processed by the acyl-CoA synthetase FadD, which permits binding to FadR and decreases FadR affinity for its target DNA sequences. This interaction enables the transcriptional regulation of FadR-responsive operons by arachidonic acid in EHEC, including the LEE. Finally, we show that arachidonic acid inhibits hallmarks of EHEC disease in a FadR-dependent manner, including EHEC attachment to epithelial cells and the formation of attaching and effacing lesions. Together, our findings delineate a molecular mechanism demonstrating how LCFAs can directly inhibit the virulence of an enteric bacterial pathogen. More broadly, our findings expand the repertoire of ligands sensed by the canonical LFCA sensing machinery in EHEC to include arachidonic acid, an important bioactive lipid that is ubiquitous within host environments. IMPORTANCE Polyunsaturated fatty acids (PUFAs) play important roles in host immunity. Manipulation of lipid content in host tissues through diet or pharmacological interventions is associated with altered severity of various inflammatory diseases. Our work introduces a defined host-pathogen interaction by which arachidonic acid, a host-derived and dietary PUFA, can impact the outcome of enteric infection with the human pathogen enterohemorrhagic Escherichia coli (EHEC). We show that long-chain fatty acids including arachidonic acid act as signaling molecules that directly suppress a key pathogenicity island in EHEC following recognition by the fatty acyl-CoA-responsive transcription factor FadR. Thus, in addition to its established effects on host immunity and its bactericidal activities against other pathogens, we demonstrate that arachidonic acid also acts as a signaling molecule that inhibits virulence in an enteric pathogen.

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Journal articles on the topic 'Foodborne diseases (DVA)'

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