New perspectives on transmission of foodborne pathogens and antimicrobial resistance.
Explore the source record for details and available documents.
Animals↗
SEARCH · PubMed Health
Results for “Foodborne pathogen”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Evaluation of universal preenrichment broth for the recovery of foodborne pathogens from milk and cheese.
The use of universal preenrichment broth for the recovery of verotoxigenic Escherichia coli, Salmonella spp., and Listeria monocytogenes from milk and cheese was examined. Universal preenrichment broth supported the growth of low inoculum levels (10 cfu/ml) of these organisms in pure cultures and in mixed cultures containing higher levels of other pathogens or bacterial flora from raw milk. This medium also supported the recovery and growth of heat-injured Salmonella spp., L. monocytogenes, and verotoxigenic E. coli at inoculum levels of 10(2) cfu/ml to yield cell levels of 10(8) cfu/ml in pure cultures and at least 10(5) cfu/ml in the presence of high levels of known competitive pathogens or microflora of cheese samples after 24 h of incubation. Universal preenrichment broth performed better than Listeria enrichment broth in supporting the recovery and growth of heat-injured L. monocytogenes and equally as well as buffered peptone water or trypticase soy broth in supporting the growth of uninjured L. monocytogenes, Salmonella spp., and verotoxigenic E. coli. Coenrichment of these pathogens in universal preenrichment broth reduced the quantity of milk or cheese samples that were required for analysis and also reduced the cost and labor involved in preparing and processing separate preenrichment media.
Animals↗
A study of the foodborne pathogens: Campylobacter, Listeria and Yersinia, in faeces from slaughter-age cattle and sheep in Australia.
In a study of faeces from 475 slaughter-age cattle and sheep from 19 herds or flocks, Campylobacter species (C. jejuni and C. coli) were cultured from all production systems studied and from 73.7 per cent (14/19) of herds or flocks. Within individual properties there was a higher prevalence in cattle than in sheep, with Campylobacter being most commonly isolated from feedlot cattle. The median prevalences and ranges were: for dairy cattle, six per cent (0-24%), feedlot beef cattle, 58 per cent (12-92%) pasture beef cattle, two per cent (0-52%), mutton sheep, 0 per cent (0-4%) and prime lambs eight per cent. Listeria ivanovii was cultured from one dairy cow but Yersinia enterocolitica was not cultured from any animal. Campylobacter is the leading bacterial causative agent of acute diarrhoea in humans in many industrialised countries. While the role of cattle and sheep in producing human campylobacteriosis either directly or via contaminated food, remains to be epidemiologically clarified, this study suggests that the production system, particularly for cattle, may be an important consideration.
Abattoirs↗
Susceptibility of antibiotic-resistant and antibiotic-sensitive foodborne pathogens to acid anionic sanitizers.
Acid anionic sanitizers for treatment of fruits and vegetables were prepared using ingredients generally recognized as safe by the U.S. Food and Drug Administration or anionic surfactants and organic acid food additives. They met the regulatory definition as sanitizers by showing bactericidal efficacy of 99.999% in 30 s against Staphylococcus aureus ATCC 6538 and Escherichia coli ATCC 11229. These sanitizers showed a broad spectrum of microbicidal activity against both gram-positive and gram-negative bacteria. Antibiotic-sensitive and resistant strains of Listeria monocytogenes and Salmonella typhimurium were equally susceptible to these sanitizers. The acid anionic sanitizers showed microbicidal efficacy equal to that of hypochlorite against Aeromonas hydrophila, E. coli O157:H7, L. monocytogenes, Pseudomonas aeruginosa, S. typhimurium, and S. aureus. Unlike most other sanitizers, these agents do not covalently react with organic components of food; unlike cationic agents, they do not leave residues. The acid anionic sanitizers are prepared using stable, biodegradable, and nontoxic ingredients. Rapid microbicidal activity and the ease of storage, transportation, and use make these sanitizers an attractive alternative to hypochlorite for sanitizing fruits and vegetables.
Anions↗
Development of a lacticin 3147-enriched whey powder with inhibitory activity against foodborne pathogens.
The broad-spectrum bacteriocin lacticin 3147, produced by Lactococcus lactis DPC3147, is inhibitory to a wide range of gram-positive food spoilage and pathogenic organisms. A 10% solution of demineralized whey powder was fermented with DPC3147 at a constant pH of 6.5. The fermentate was spray dried, and the resulting powder exhibited inhibitory activity. The ability of the lacticin 3147-enriched powder to inhibit Listeria monocytogenes Scott A and Staphylococcus aureus 10 was assessed in buffer at both acidic (pH 5) and neutral (pH 7) pH. In addition, the ability of the powder to inhibit L. monocytogenes Scott A in an infant milk formulation was assessed. Resuspension of approximately 10(8) midexponential phase L. monocytogenes Scott A cells in a 10% solution of the lacticin 3147-enriched powder resulted in a 1,000-fold reduction in viable cells at pH 5 and pH 7 after 3 h at 30 degrees C. In the case of S. aureus 10, resuspension of 2.5 x 10(7) midexponential phase cells in a 15% solution of the lacticin 3147-enriched powder at pH 5 resulted in only a 10-fold reduction in viable cell counts, compared with a 1,000-fold reduction at pH 7, following incubation for 3 h at 30 degrees C. The use of the lacticin 3147 powder in an infant milk formulation resulted in greater than a 99% kill of L. monocytogenes within 3 h at 30 degrees C. These results suggest that this bioactive lacticin 3147 food ingredient may find applications in many different foods, including those with pH close to neutrality.
Animals↗
Evaluation of batch and semicontinuous application of high hydrostatic pressure on foodborne pathogens in salsa.
The effects of high hydrostatic pressure (HPP; 545 MPa) on strains of Escherichia coli O157:H7, Listeria monocytogenes, enterotoxigenic Staphylococcus aureus, and nonpathogenic microorganisms were studied in tomato-based salsa. Products were evaluated for the survival of the inoculated pathogens following HPP treatment and after storage at 4 degrees C and 21 to 23 degrees C for up to 2 months. Inoculated samples without HPP treatment, stored under the same conditions, were also evaluated to determine the effects of the acid environment of salsa on the survival of inoculated strains. None of the inoculated pathogens were detected in the HPP-treated samples for all treatments throughout the storage period. Inoculated pathogens were detected in the non-HPP-treated samples stored at 4 degrees C after 1 month, with L. monocytogenes showing the highest level of survivors. In the non-HPP-treated samples stored at 21 to 23 degrees C, E. coli and S. aureus were not detected after 1 week, but L. monocytogenes was detected in low levels. Studies with nonpathogenic strains of the pathogens were conducted at Oregon State University using HPP treatments in a semicontinuous production system. The nonpathogenic microorganisms (E. coli, Listeria innocua, Listeria welshimeri, and nonenterotoxigenic S. aureus) were inoculated together into a feeder tank containing 100 liters of salsa. Microbiological results of samples collected before HPP treatment and from the aseptic filler were similar to those obtained for the pathogenic strains. No survivors were detected in any of the HPP-treated samples.
Bacteria↗
Effects of antibacterial dishwashing liquid on foodborne pathogens and competitive microorganisms in kitchen sponges.
In response to increasing concern about home hygiene, the use of antibacterial products to reduce microorganisms in kitchen sponges and cleaning cloths is strongly promoted by some producers of detergent for domestic use. The effects of an antibacterial dishwashing liquid on Escherichia coli, Salmonella Enteritidis, Staphylococcus aureus, and Bacillus cereus were investigated in a modified suspension test and in used sponges with and without food residues under laboratory conditions. A limited study was conducted in households to assess the efficacy of antibacterial dishwashing liquid as used by the consumer. In the suspension tests, S. aureus and B. cereus were shown to be susceptible to low concentrations of antibacterial dishwashing liquid (0.5%), whereas E. coli and Salmonella Enteritidis maintained their initial numbers for at least 24 h at 25 degrees C. At higher concentrations (2 to 4%), all test organisms decreased to below the detection limit after 24 h. Over a 24-h period, the antibacterial dishwashing liquid did not significantly reduce these organisms in used sponges in which food residues were present. The antibacterial product did not reduce the competitive microorganisms either. Similar results were found for sponges involved in daily household use. The results of this study demonstrate that the antibacterial dishwashing liquid was effective in reducing pathogens in the suspension test but not in the used sponges. This finding indicates that to determine the efficacy of antibacterial products, their use in a household setting must be considered.
Bacillus cereus↗
Microbial antagonists of foodborne pathogens on fresh, minimally processed vegetables.
On many types of raw or minimally processed foods, the bacterial microbiota is often composed of mixed species. The activities of one bacterial species may influence the growth and activities of others that are present. The objective of this project was to evaluate the microbial composition of fresh and minimally processed vegetables to determine if naturally occurring bacteria on produce are competitive with or antagonistic to potentially encountered pathogens. Naturally occurring bacteria were obtained from ready-to-eat salad vegetables on four occasions to allow for seasonal variation. Minimally processed vegetables were sampled at various stages in their processing from raw vegetables to packaged products. Some portions were analyzed microbiologically within 24 h, while other portions were stored refrigerated and analyzed after 72 h. Microbiological analysis was conducted for bacterial enumeration and to obtain isolates. An agar spot method was used to screen isolates for antimicrobial activity against Staphylococcus aureus ATCC 27664, Escherichia coli O157:H7 E009, Listeria monocytogenes LCDC 81-861, and Salmonella Montevideo. Of the 1,180 isolates screened for inhibitory activity, 37 (3.22%) were found to have various degrees of inhibitory activity against at least one test pathogen. Many isolates showed inhibitory activity against all four pathogens. The isolates with the most extensive inhibition were removed from finished lettuce piece shreds. Of the 37 inhibitory isolates, 34 (91.9%) were gram negative. All isolates with inhibitory activity are able to multiply at both 4 and 10 degrees C.
Bacterial Physiological Phenomena↗
Inactivation of foodborne pathogens in milk using dynamic high pressure.
Improving the microbiological safety of perishable foods is currently a major preoccupation in the food industry. The aim of this study was to investigate the inactivation of three major food pathogens (Listeria monocytogenes [LSD 105-1], Escherichia coli O157:H7 [ATCC 35150], and Salmonella enterica serotype Enteritidis ATCC [13047]) by dynamic high pressure (DHP) in order to evaluate its potential as a new alternative for the cold pasteurization of milk. The effectiveness of DHP treatment against L. monocYtogenes, E. coli O157:H7, and Salmonella Enteritidis was first evaluated in 0.01 M phosphate-buffered saline (PBS) at pH 7.2 as a function of applied pressure (100, 200, and 300 MPa) and of the number of passes (1, 3, and 5) at 25 degrees C. A single pass at 100 MPa produced no significant inactivation of the three pathogens, while increasing the pressure up to 300 MPa or the number of passes to five increased inactivation. From an initial count of 8.3 log CFU/ml, complete inactivation of viable L. monocytogenes was achieved after three successive passes at 300 MPa, while 200-MPa treatments with three and five passes completely eliminated viable Salmonella Enteritidis and E. coli O157:H7, respectively. The effectiveness of DHP for the inactivation of these pathogens was compared to that of hydrostatic high pressure (HHP) using the same pressure (200 MPa, single pass at 25 degrees C). In general, two additional log reductions in viable count were obtained with DHP DHP was less effective against L. monocytogenes and E. coli O157:H7 in raw milk than in PBS. After five passes at 200 MPa, an 8.3-log reduction was obtained for E. coli O157:H7, while a reduction of about 5.8 log CFU/ml was obtained for L. monocytogenes exposed to 300 MPa for five passes. Exposing milk or buffer samples to mild heating (45 to 60 degrees C) prior to dynamic pressurization enhanced the lethal effect of DHP The inactivation of pathogens also depended on the initial bacterial concentration. The highest reduction was obtained when the bacterial load did not exceed 10(5) CFU/ml. In conclusion, DHP was shown to be very effective for the destruction of the tested pathogens. It offers a promising alternative for the cold pasteurization of milk and possibly other liquid foods.
Animals↗
Composition and antimicrobial properties of Sardinian Juniperus essential oils against foodborne pathogens and spoilage microorganisms.
In this work, the chemical compositions and antimicrobial properties of Juniperus essential oils and of their main components were determined. Five berry essential oils obtained from different species of Juniperus growing wild in Sardinia were analyzed. The components of the essential oils were identified by gas chromatography-mass spectrometry (GC-MS) analysis. The antimicrobial activities of the oils and their components against food spoilage and pathogenic microorganisms were determined by a broth microdilution method. The GC-MS analysis showed a certain variability in the concentrations of the main constituents of the oils. Alpha-pinene was largely predominant in the oils of the species J. phoenicea subsp. turbinata and J. oxycedrus. Alpha-pinene and myrcene constituted the bulk (67.56%) of the essential oil of J. communis. Significant quantitative differences were observed for myrcene, delta-3-carene, and D-germacrene. The results of the antimicrobial assay show that the oils of J. communis and J. oxycedrus failed to inhibit any of the microorganisms at the highest concentrations tested (MLC > or = 900 microg/ml), while the oils extracted from J. turbinata specimens were active against fungi, particularly against a strain of Aspergillus flavus (an aflatoxin B1 producer). Of the single compounds tested, delta-3-carene was found to possess the broadest spectrum of activity and appeared to contribute significantly to the antifungal activity observed for J. turbinata oils. This activity may be helpful in the prevention of aflatoxin contamination for many foods.
Antifungal Agents↗
Surface material, temperature, and soil effects on the survival of selected foodborne pathogens in the presence of condensate.
The effects of surface type (stainless steel, acetal resin, and fiberglass reinforced plastic wall paneling [FRP]), soil, and temperature on the survival of Listeria monocytogenes, Salmonella spp., and Yersinia enterocolitica, in the presence of condensate were evaluated. Surface coupons--half soiled with sterile porcine serum--were exposed to cell suspensions made from individual five-strain cocktails composed of organisms from the same genus (10(7) CFU/ml) in Butterfield's phosphate buffer and incubated for 2 h at 25 degrees C allowing attachment of cells to coupon surfaces. Coupons were rinsed to remove unattached cells, incubated at either 4 or 10 degrees C under condensate-forming conditions, and sampled at six time intervals over a 15-day period. For enumeration, cells were removed from the coupons by vigorous shaking in 100 ml of Butterfield's phosphate buffer with 3 g of glass beads and plated on tryptic soy agar with 0.6% yeast extract. Stainless steel did not support the survival of Listeria as well as acetal resin or FRP. Acetal resin and stainless steel were less supportive of Salmonella than FRP. All surfaces supported the survival of Yersinia over the 15-day trial equally. Temperature had little effect on survival of all organisms across all surfaces with one exception. However, Yersinia displayed growth on FRP at 10 degrees C. but death at 4 degrees C. Serum had a protective effect on L. monocytogenes on all surfaces, with populations sustained at significantly (P < or = 0.05) higher numbers over time than unsoiled coupons. Serum didnot effect survival of Salmonella or Yersinia on stainless steel, acetal resin, or FRP.
Bacterial Adhesion↗
In vitro antimicrobial activity of essential oils from aromatic plants against selected foodborne pathogens.
The purpose of this study was to examine the effectiveness of selected essential oils for the control of growth and survival of pathogenic microorganisms of significant importance in food hygiene and to determine whether the antimicrobial effect was due to the major compounds of the oils. MIC and MBC were determined by the tube dilution method. Essential oils from Thymus vulgaris from Spain and France, Salvia sclarea, Salvia officinalis, Salvia lavandulifolia, Lavandula latifolia, Lavandula angustifolia, three hybrids of Lavandula latifolia x Lavandula angustifolia (Lavandin 'Super', Lavandin 'Abrialis', and Lavandin 'Grosso'), Rosmarinus officinalis, Hissopus officinalis, and Satureja montana were evaluated. Inhibition ranged from the strong activity of Satureja montana and Thymus vulgaris (France) to no inhibition with Salvia sclarea and Hissopus officinalis for each of the test strains: Salmonella Enteritidis, Salmonella Typhimurium, Escherichia coli O157:H7, Yersinia enterocolitica, Shigella flexneri, Listeria monocytogenes serovar 4b, and Staphylococcus aureus. Because some of the essential oils were highly inhibitory in small quantities to selected pathogenic microorganisms, they may provide alternatives to conventional antimicrobial additives in foods.
Bacteria↗
Occurrence of selected foodborne pathogens on poultry and poultry giblets from small retail processing operations in Trinidad.
We conducted a study to determine quantitatively and qualitatively the presence of Campylobacter spp., Escherichia coli, staphylococci, total coliforms, total aerobic bacteria, and Salmonella on broiler carcasses from selected small retail processors in Trinidad. We used standard media and procedures for detection and quantification. All carcass and weep samples were positive for aerobic bacteria, E. coli, total coliforms, and staphylococci. Significant differences in the mean counts of aerobic bacteria were observed for samples of carcass (P = 0.001), weep (P = 0.038), and liver and heart (P = 0.017). There was a significant difference (P < 0.05) in the prevalence of E. coli and Campylobacter for liver and heart samples and gizzard samples across various areas (health divisions) in Trinidad and for Campylobacter jejuni and Campylobacter coli for offal samples. The prevalence of Salmonella in carcass, drip, gizzard, and liver and heart samples was 7.3, 3.1, 2.1, and 1.0%, respectively, and three serotypes, Salmonella Kiambu (53.8%), Salmonella Kentucky (38.5%), and Salmonella Mbandaka (7.7%) were isolated. Of the six groups of microbes considered with respect to sale activity, the differences in the prevalence of Campylobacter in medium-activity sale shops (95.8%) and low-activity sale shops (83.3%) and the mean counts of staphylococci for medium-activity sale shops (5.5 +/- 0.9) and low-activity sale shops (5.1 +/- 0.8) were statistically significant (P < 0.05). Carcasses rinsed in a stagnant system had a significantly higher (P < 0.05) prevalence (92.3%) and mean count per milliliter (3.1 +/- 0.7) for Campylobacter compared with 77.8% and 2.7 +/- 0.7 for shops that rinsed with constantly running water. The frequency of rinse water change significantly (P = 0.04) affected the prevalence of Salmonella on carcasses. It is recommended that a quality control system be introduced for these shops, particularly with respect to evisceration and rinsing practices.
Animals↗
Rabbit meat as a source of bacterial foodborne pathogens.
Even though worldwide production of rabbit meat is >1,000,000 tons, little information is available for rabbit meat microbiology. This study provides data on the prevalence of Salmonella, Escherichia coli O157:H7, Yersinia enterocolitica, Listeria spp., motile Aeromonas spp., and Staphylococcus aureus on rabbit meat. A total of 24 rabbit carcasses from two abattoirs and 27 rabbit meat packages from supermarket displays were examined. In addition to culturing methods, associated virulence genes were investigated by PCR in suspect isolates and samples. Neither Salmonella nor E. coli O157:H7 was detected. All samples were negative for virulence-associated invA, stx1, and stx2 genes. At one abattoir, two carcasses (3.9%) carried Y. enterocolitica yst-, and two were positive for the yst gene, although viable Y. enterocolitica cells were not recovered from these samples. Seven samples (13.7%) were contaminated with Listeria. Of them, three were positive for hly and iap genes (Listeria monocytogenes hly+ / iap+), two carried Listeria seeligeri, one carried Listeria ivanovii, and one carried Listeria innocua. For detectable motile Aeromonas spp. (average count, 1.77 +/- 0.62 log CFU/g), the contamination rate was 35.3%, although ca. 90% of the samples were positive for the aerA and/or hlyA genes. The majority of aeromonad isolates were Aeromonas hydrophila aerA+ / hlyA+. Aeromonas caviae, Aeromonas popoffii, Aeromonas schubertii, and the two biovars of Aeromonas veronii were also isolated. The prevalence of S. aureus contamination (average count, 1.37 +/- 0.79 log CFU/g) was 52.9%. Among 27 S. aureus isolates, two harbored genes for staphylococcal enterotoxin B (seb), and two harbored genes for staphylococcal enterotoxin C (sec). The remaining isolates were negative for sea, seb, sec, sed, and see.
Abattoirs↗
Some foodborne pathogens can hasten progression of HIV.
Explore the source record for details and available documents.
Communicable Diseases↗
DNA microarray technology used for studying foodborne pathogens and microbial habitats: minireview.
Microarray analysis is an emerging technology that has the potential to become a leading trend in bacterial identification in food and feed improvement. The technology uses fluorescent-labeled probes amplified from bacterial samples that are then hybridized to thousands of DNA sequences immobilized on chemically modified glass slides. The whole gene or open reading frame(s) is represented by a polymerase chain reaction fragment of double-strand DNA, approximately 1000 base pair (bp) or 20-70 bp single-strand oligonucleotides. The technology can be used to identity bacteria and to study gene expression in complex microbial populations, such as those found in food and gastrointestinal tracts. Data generated by microarray analysis can be potentially used to improve the safety of our food supply as well as ensure the efficiency of animal feed conversion to human food, e.g., in meat and milk production by ruminants. This minireview addresses the use of microarray technology in bacterial identification and gene expression in different microbial systems and in habitats containing mixed populations of bacteria.
Animals↗
Listeria monocytogenes: a foodborne pathogen.
Listeriosis, caused by Listeria monocytogenes, appears to be increasing in incidence worldwide. The disease is of great concern to the food industry. A recent outbreak in California was linked to the consumption of Mexican-style soft cheese and involved more than 300 cases, 30% of which were fatal. L. monocytogenes can be found in a variety of dairy products, leafy vegetables, fish and meat products. It can grow in refrigerated foods and is more heat resistant than most vegetative microbes. The epidemiologic features of listeriosis are poorly understood, and the minimum infectious dose is unknown. Those predisposed to listeriosis include immunocompromised people and pregnant women and their fetuses. Meningitis, spontaneous abortion and septicemia are the primary manifestations of the disease. Early recognition is critical for successful treatment, and ampicillin is the preferred drug. Listeriosis should be considered in any febrile patient with neurologic symptoms of unknown origin, as well as in women with unexplained recurrent miscarriages, premature labour or fetal death. A food source should be the prime suspect if any isolated case or outbreak occurs.
Abortion, Spontaneous↗
Risk assessment prediction from genome sequences: promises and dreams.
The application of bacterial genomics opens new avenues of research on foodborne pathogens. Foodborne pathogens must be able to colonize their hosts and survive transmission from host to host. Different groups of genes are involved in the processes of survival, colonization, and virulence, and such genes are potential targets for risk assessment and intervention strategies. Filtering from genome sequences the genes relevant to these processes is a major challenge, and although many tools are already available for analyses, this type of data mining is just beginning. For the simplest application, gene comparison, it is important to know how gene function, for instance in virulence, is being defined and tested. In other genomic applications, reserachers look for specific properties or characteristics of (virulence) genes to identify novel gene candidates. Each approach has pitfalls, and gene candidates must be tested in the lab to confirm their function. Models for colonization and virulence are available for most although not all pathogens. Models for survival and stress responses are needed to increase the utilization of genomic approaches to risk assessment. Here, I discuss how genome sequences are likely to help in microbial risk assessment of foodborne pathogens and how dreams may become promises.
Animals↗