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Ugeskrift For Laeger Nov 2023In this case report, a previously healthy six-year-old presented with fever and altered mental status, and was found to have bacteremia with Listeria monocytogenes,...
In this case report, a previously healthy six-year-old presented with fever and altered mental status, and was found to have bacteremia with Listeria monocytogenes, acquired from premade fish balls. Invasive L. monocytogenes infection usually occurs in immunocompromised or newborns but may occasionally occur in healthy children with food-borne gastroenteritis. L. monocytogenes should be considered in patients with severe infection and symptoms of gastroenteritis, particularly since ceftriaxone, the Danish standard treatment for meningitis in children, does not cover L. monocytogenes.
Topics: Child; Humans; Bacteremia; Ceftriaxone; Gastroenteritis; Listeria monocytogenes; Meningitis, Listeria
PubMed: 37987449
DOI: No ID Found -
Microbial Ecology Nov 2023Listeria monocytogenes, the third most deleterious zoonotic pathogen, is a major causative agent of animal and human listeriosis, an infection related to the consumption... (Review)
Review
Listeria monocytogenes, the third most deleterious zoonotic pathogen, is a major causative agent of animal and human listeriosis, an infection related to the consumption of contaminated food products. Even though, this pathogen has been responsible for the outbreaks of foodborne infections in the early 1980s, the major outbreaks have been reported during the past two decades. Listeriosis infection in the host is a rare but life-threatening disease with major public health and economic implications. Extensive reports on listeriosis outbreaks are associated with milk and milk products, meat and meat products, and fresh produce. This bacterium can adapt to any environmental and stress conditions, making it a prime causative agent for major foodborne diseases. The pathogen could survive an antibiotic treatment and persist in the host cell, thereby escaping the standard diagnostic practices. The current review strives to provide concise information on the epidemiology, serotypes, and pathogenesis of the L. monocytogenes to decipher the knowledge on the endurance of the pathogen inside the host and food products as a vehicle for Listeria contaminations. In addition, various detection methods for Listeria species from food samples and frontline regimens of L. monocytogenes treatment have also been discussed.
Topics: Animals; Humans; Listeria monocytogenes; Listeria; Virulence; Food Microbiology; Listeriosis; Virulence Factors
PubMed: 37479828
DOI: 10.1007/s00248-023-02269-9 -
Microbiology and Immunology Oct 2023The high mortality rate associated with Listeria monocytogenes can be attributed to its ability to invade the body systemically and to activate inflammasomes. Both of... (Review)
Review
The high mortality rate associated with Listeria monocytogenes can be attributed to its ability to invade the body systemically and to activate inflammasomes. Both of these processes are facilitated by expressing a major virulence factor known as listeriolysin O, a 56 kDa pore-forming protein encoded by the hly gene. Listeriolysin O plays a crucial role in the pathogenesis of the bacterium by facilitating the escape of the pathogen from the phagosome into the cytosol. This process is essential for the successful establishment of infection. In addition, listeriolysin O is known as an immunomodulator that activates host signal transduction. In addition to listeriolysin O, Listeria expresses a variety of bacterial ligands, such as lipoteichoic acid, nucleotide, and flagellin, that are recognized by host intracellular pattern-recognition receptors including Nod-like receptors, AIM2-like receptors, and RIG-I-like receptors. This review introduces intracellular recognition of Listeria monocytogenes since recent studies have revealed that the activation of inflammasome exacerbates Gram-positive bacteria infection.
Topics: Humans; Listeria monocytogenes; Inflammasomes; Hemolysin Proteins; Phagosomes; Cytosol; Virulence Factors; Listeriosis
PubMed: 37461376
DOI: 10.1111/1348-0421.13091 -
Microorganisms Sep 2023The prevalence of in 30 samples of poultry was determined using culture-dependent (isolation on OCLA and confirmation by conventional polymerase chain reaction -PCR-,...
The prevalence of in 30 samples of poultry was determined using culture-dependent (isolation on OCLA and confirmation by conventional polymerase chain reaction -PCR-, OCLA&PCR) and culture-independent (real-time polymerase chain reaction, q-PCR) methods. was detected in 15 samples (50.0%) by OCLA&PCR and in 20 (66.7%) by q-PCR. The concentrations (log cfu/g) of (q-PCR) ranged from 2.40 to 5.22 (total cells) and from <2.15 to 3.93 (viable cells). The two methods, q-PCR using a viability marker (v-PCR) and OCLA&PCR (gold standard), were compared for their capacity to detect viable cells of , with the potential to cause human disease. The values for sensitivity, specificity and efficiency of the v-PCR were 100%, 66.7% and 83.3%, respectively. The agreement between the two methods (kappa coefficient) was 0.67. The presence of nine virulence genes (, , , , , , , and ) was studied in 45 isolates (three from each positive sample) using PCR. All the strains harbored between six and nine virulence genes. Fifteen isolates (33.3% of the total) did not show the potential to form biofilm on a polystyrene surface, as determined by a crystal violet assay. The remaining strains were classified as weak (23 isolates, 51.1% of the total), moderate (one isolate, 2.2%) or strong (six isolates, 13.3%) biofilm producers. The strains were tested for susceptibility to a panel of 15 antibiotics. An average of 5.11 ± 1.30 resistances per isolate was observed. When the values for resistance and for reduced susceptibility were taken jointly, this figure rose to 6.91 ± 1.59. There was a prevalence of resistance or reduced susceptibility of more than 50.0% for oxacillin, cefoxitin, cefotaxime, cefepime ciprofloxacin, enrofloxacin and nitrofurantoin. For the remaining antibiotics tested, the corresponding values ranged from 0.0% for chloramphenicol to 48.9% for rifampicin. The high prevalence and level of with numerous virulence factors in poultry underline how crucial it is to follow correct hygiene procedures during the processing of this foodstuff in order to reduce the risk of human listeriosis.
PubMed: 37764076
DOI: 10.3390/microorganisms11092232 -
Journal of Veterinary Research Dec 2023is one of the most dangerous food-borne pathogens and is responsible for human listeriosis, a severe disease with a high mortality rate, especially among the elderly,...
is one of the most dangerous food-borne pathogens and is responsible for human listeriosis, a severe disease with a high mortality rate, especially among the elderly, pregnant women and newborns. Therefore, this bacterium has an important impact on food safety and public health. It is able to survive and even grow in a temperature range from -0.4°C to 45°C, a broad pH range from 4.6 to 9.5 and at a relatively low water activity (a < 0.90), and tolerates salt content up to 20%. It is also resistant to ultraviolet light, biocides and heavy metals and forms biofilm structures on a variety of surfaces in food-production environments. These features make it difficult to remove and allow it to persist for a long time, increasing the risk of contamination of food-production facilities and ultimately of food. In the present review, the key mechanisms of the pathogen's survival and stress adaptation have been presented. This information may grant better understanding of bacterial adaptation to food environmental conditions.
PubMed: 38130454
DOI: 10.2478/jvetres-2023-0068 -
Applied Microbiology and Biotechnology Jun 2024Bacteriocins have the potential to effectively improve food-borne infections or gastrointestinal diseases and hold promise as viable alternatives to antibiotics. This...
Bacteriocins have the potential to effectively improve food-borne infections or gastrointestinal diseases and hold promise as viable alternatives to antibiotics. This study aimed to explore the antibacterial activity of three bacteriocins (nisin, enterocin Gr17, and plantaricin RX-8) and their ability to attenuate intestinal barrier dysfunction and inflammatory responses induced by Listeria monocytogenes, respectively. Bacteriocins have shown excellent antibacterial activity against L. monocytogenes without causing any cytotoxicity. Bacteriocins inhibited the adhesion and invasion of L. monocytogenes on Caco-2 cells, lactate dehydrogenase (LDH), trans-epithelial electrical resistance (TEER), and cell migration showed that bacteriocin improved the permeability of Caco-2 cells. These results were attributed to the promotion of tight junction proteins (TJP) assembly, specifically zonula occludens-1 (ZO-1), occludin, and claudin-1. Furthermore, bacteriocins could alleviate inflammation by inhibiting the mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) pathways and reducing the secretion of interleukin-6 (IL-6), interleukin-1 β (IL-1β) and tumor necrosis factor α (TNF-α). Among three bacteriocins, plantaricin RX-8 showed the best antibacterial activity against L. monocytogenes and the most pronounced protective effect on the intestinal barrier due to its unique structure. Based on our findings, we hypothesized that bacteriocins may inhibit the adhesion and invasion of L. monocytogenes by competing adhesion sites. Moreover, they may further enhance intestinal barrier function by inhibiting the expression of L. monocytogenes virulence factors, increasing the expression of TJP and decreasing the secretion of inflammatory factors. Therefore, bacteriocins will hopefully be an effective alternative to antibiotics, and this study provides valuable insights into food safety concerns. KEY POINTS: • Bacteriocins show excellent antibacterial activity against L. monocytogenes • Bacteriocins improve intestinal barrier damage and inflammatory response • Plantaricin RX-8 has the best protective effect on Caco-2 cells damage.
Topics: Listeria monocytogenes; Bacteriocins; Humans; Caco-2 Cells; Anti-Bacterial Agents; Inflammation; NF-kappa B; Bacterial Adhesion; Tight Junction Proteins; Cytokines; Listeriosis; Cell Movement
PubMed: 38896287
DOI: 10.1007/s00253-024-13228-w -
Environmental persistence of Listeria monocytogenes and its implications in dairy processing plants.Comprehensive Reviews in Food Science... Nov 2023Listeriosis, an invasive illness with a fatality rate between 20% and 30%, is caused by the ubiquitous bacterium Listeria monocytogenes. Human listeriosis has long been... (Review)
Review
Listeriosis, an invasive illness with a fatality rate between 20% and 30%, is caused by the ubiquitous bacterium Listeria monocytogenes. Human listeriosis has long been associated with foods. This is because the ubiquitous nature of the bacteria renders it a common food contaminant, posing a significant risk to the food processing sector. Although several sophisticated stress coping mechanisms have been identified as significant contributing factors toward the pathogen's persistence, a complete understanding of the mechanisms underlying persistence across various strains remains limited. Moreover, aside from genetic aspects that promote the ability to cope with stress, various environmental factors that exist in food manufacturing plants could also contribute to the persistence of the pathogen. The objective of this review is to provide insight into the challenges faced by the dairy industry because of the pathogens' environmental persistence. Additionally, it also aims to emphasize the diverse adaptation and response mechanisms utilized by L. monocytogenes in food manufacturing plants to evade environmental stressors. The persistence of L. monocytogenes in the food processing environment poses a serious threat to food safety and public health. The emergence of areas with high levels of L. monocytogenes contamination could facilitate Listeria transmission through aerosols, potentially leading to the recontamination of food, particularly from floors and drains, when sanitation is implemented alongside product manufacturing. Hence, to produce safe dairy products and reduce the frequency of outbreaks of listeriosis, it is crucial to understand the factors that contribute to the persistence of this pathogen and to implement efficient control strategies.
Topics: Humans; Listeria monocytogenes; Food Microbiology; Food Contamination; Listeriosis; Public Health
PubMed: 37680027
DOI: 10.1111/1541-4337.13234 -
Food Science and Technology... Dec 2023This study aimed to evaluate the behavior of during the manufacture and storage of artisanal kefir. A five-strain cocktail of was introduced (at 3.0 log CFU/mL) into...
This study aimed to evaluate the behavior of during the manufacture and storage of artisanal kefir. A five-strain cocktail of was introduced (at 3.0 log CFU/mL) into UHT milk as a pre-fermentation contaminant. The growth of lactic acid bacteria and yeasts was monitored during the 24-h fermentation period of milk with two types of kefir grains at 20 °C and the subsequent storage of kefir under adequate (4 °C) and inadequate (10 °C) refrigerated-storage conditions. grew into much higher cell densities (5.3-5.8 log CFU/mL) by the end of the fermentation period, but the final (24-h) counts were substantially lower than those obtained in the corresponding control trials with unfermented milk (7.2 log CFU/mL). The growth rate of during fermentation differed depending on the type of kefir grain used. During the subsequent 11-day storage of the kefir filtrates at 4 °C or 10 °C, the behavior of varied from no growth to further population increases (of up to 1.1 log CFU/mL), depending on the storage temperature, but also depending on the type of kefir grain and the grain surface-to-weight ratio that had been used to ferment the milk. This study highlights the need for strict adherence to good hygiene practices during artisanal kefir making and shows that can sustain considerable growth during milk fermentation and further grow during the subsequent cold storage of kefir, particularly under inadequate refrigerated storage conditions.
Topics: Animals; Kefir; Listeria monocytogenes; Milk; Food Microbiology; Temperature; Colony Count, Microbial
PubMed: 35903903
DOI: 10.1177/10820132221117462 -
Journal of Food Protection Oct 2023Imported mangoes have been linked to outbreaks of salmonellosis in the USA. The purpose of this research was to evaluate the persistence and growth kinetics of...
Imported mangoes have been linked to outbreaks of salmonellosis in the USA. The purpose of this research was to evaluate the persistence and growth kinetics of Salmonella and Listeria monocytogenes on the intact surface of whole 'Ataulfo', 'Kent', and 'Tommy Atkins' mangoes stored at three different temperatures. L. monocytogenes was also evaluated on fresh-cut 'Tommy Atkins' mangoes stored at 4, 12, 20 ± 2°C. Whole mangoes were spot inoculated with rifampicin-resistant pathogen cocktails (6 log CFU/mango) onto the midsection of whole fruit (n = 6). Fruit was stored at 12, 20, or 30 ± 2°C and sampled for up to 28 days. The specific growth rates derived from DMFit models as a function of time were used to develop secondary models. On 'Kent' mangoes, Salmonella had a population increase from 0.3 to 1.1 log CFU/mango with a linear growth rate of ∼0.004, 0.01, and 0.06 log CFU/mango/h at 12, 20, and 30°C, respectively. At 20 and 30°C, Salmonella growth rates were significantly higher than 12°C (P < 0.05). No clear Salmonella growth trend was observed; populations decreased up to 1.6 log CFU/mango on 'Tommy Atkins' and 'Ataulfo' at 12°C. Populations of L. monocytogenes on whole and fresh-cut mangoes declined regardless of temperature and storage period. Food safety during storage should be the top priority for fresh-cut tropical fruit processors.
Topics: Food Microbiology; Listeria monocytogenes; Mangifera; Colony Count, Microbial; Salmonella; Temperature; Food Handling
PubMed: 37634809
DOI: 10.1016/j.jfp.2023.100151