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Microbial Genomics Jan 2024is a food-borne pathogen, typically affecting the elderly, immunocompromised patients and pregnant women. The aim of this study was to determine the population...
is a food-borne pathogen, typically affecting the elderly, immunocompromised patients and pregnant women. The aim of this study was to determine the population structure of clonal complex 1 (CC1) in the UK and describe the genomic epidemiology of this clinically significant CC. We interrogated a working dataset of 4073 sequences of isolated between January 2015 and December 2020 from human clinical specimens, food and/or food-production environments. A minimum spanning tree was reconstructed to determine the population structure of in the UK. Subsequent analysis focused on CC1, as the cause of the highest proportion of invasive listeriosis in humans. Sequencing data was integrated with metadata on food and environmental isolates, and information from patient questionnaires, including age, sex and clinical outcomes. All isolates either belonged to lineage I (=1299/4073, 32%) or lineage II (=2774/4073, 68%), with clinical isolates from human cases more likely to belong to lineage I (=546/928, 59%) and food isolates more likely to belong to lineage II (=2352/3067, 77%). Of the four largest CCs, CC1 (=237) had the highest proportion of isolates from human cases of disease (CC1 =160/237, 67.5 %; CC121 =13/843, 2 %; CC9 =53/360, 15 %; CC2 =69/339, 20%). Within CC1, most cases were female (=95/160, 59%, =0.01771) and the highest proportion of cases were in people >60 years old (39/95, 41%, =1.314×10) with a high number of them aged 20-39 years old (=35/95, 37%) most linked to pregnancy-related listeriosis (=29/35, 83%). Most of the male cases were in men aged over 60 years old (40/65, 62%), and most of the fatal cases in both males and females were identified in this age group (42/55, 76%). Phylogenetic analysis revealed 23 5 SNP single linkage clusters comprising 80/237 (34 %) isolates with cluster sizes ranging from 2 to 19. Five 5 SNP clusters comprised isolates from human cases and an implicated food item. Expanding the analysis to 25 SNP single linkage clusters resolved an additional two clusters linking human cases to a potential food vehicle. Analysis of demographic and clinical outcome data identified CC1 as a clinically significant cause of invasive listeriosis in the elderly population and in women of child-bearing age. Phylogenetic analysis revealed the population structure of CC1 in the UK comprised small, sparsely populated genomic clusters. Only clusters containing isolates from an implicated food vehicle, or food processing or farming environments, were resolved, emphasizing the need for clinical, food and animal-health agencies to share sequencing data in real time, and the importance of a One Health approach to public-health surveillance of listeriosis.
Topics: Pregnancy; Animals; Male; Humans; Female; Aged; Middle Aged; Young Adult; Adult; Listeria monocytogenes; Phylogeny; Genomics; Listeriosis; United Kingdom
PubMed: 38165396
DOI: 10.1099/mgen.0.001155 -
International Journal of Food... Jan 2024Listeria monocytogenes clonal complex 7 (CC7), belonging to lineage II, is the most common subtype among clinical listeriosis isolates in Norway, and is also commonly...
Listeria monocytogenes clonal complex 7 (CC7), belonging to lineage II, is the most common subtype among clinical listeriosis isolates in Norway, and is also commonly found in Norwegian food industry and outdoor environments. In the present study, the relative prevalence of CCs among clinical isolates of L. monocytogenes in European countries during 2010-2015 was determined. Then, phylogenomic and comparative genomic analyses was performed for 115 Norwegian and 255 international reference genomes from various sources, to examine potential explanations underlying the high prevalence of CC7 among Norwegian listeriosis cases. Selected isolates were also compared using in vitro virulence assays. The results showed a high relative prevalence of CC7 in clinical isolates from Norway and the neighboring Nordic countries Sweden and Finland. In contrast to in most other European countries, lineage II dominated among clinical isolates in these countries. Phylogenetic analysis of the 370 CC7 isolates separated the genomes into four clades, with the majority of Norwegian isolates (69 %) clustered in one of these clades, estimated to have diverged from the other clades around year 1830. The Norwegian isolates within this clade were widely distributed in different habitats; several (poultry) meat processing factories, a salmon processing plant, in nature, farms, and slugs, and among human clinical isolates. In particular, one pervasive CC7 clone was found across three poultry processing plants and one salmon processing plant, and also included three clinical isolates. All analysed CC7 isolates harbored the same set of 72 genes involved in both general and specific stress responses. Divergence was observed for plasmid-encoded genes including genes conferring resistance against arsenic (Tn554-arsCBADR), cadmium (cadA1C1 and cadA2C2), and the biocide benzalkonium chloride (bcrABC). No significant difference in prevalence of these genes was seen between isolates from different habitats or sources. Virulence attributes were highly conserved among the CC7 isolates. In vitro virulence studies of five representative CC7 isolates revealed a virulence potential that, in general, was not significantly lower than that of the control strain EGDe, with isolate-dependent differences that could not be correlated with genetic determinants. The study shows that CC7 is widespread in Norway, and that a pervasive CC7 clone was present in food processing plants. The study highlights the importance of CC7 and lineage II strains in causing listeriosis and shows that more research is needed to understand the reasons behind geographical differences in CC prevalence.
Topics: Animals; Humans; Listeria monocytogenes; Phylogeny; Food Microbiology; Listeriosis; Poultry; Genomics
PubMed: 37977076
DOI: 10.1016/j.ijfoodmicro.2023.110482 -
Le Infezioni in Medicina 2023Listeriosis is a known cause of community acquired bacterial meningitis/meningoencephalitis. It occurs more frequently in neonates, older people and immunocompromised...
BACKGROUND
Listeriosis is a known cause of community acquired bacterial meningitis/meningoencephalitis. It occurs more frequently in neonates, older people and immunocompromised hosts. Rarely, brain abscesses can complicate the course of infection, which poses a difficulty in the management and elevates morbidity and mortality. Myasthenia gravis is an autoimmune disease that often requires immunosuppressive treatment, which increases the risk for invasive infections.
CASE DESCRIPTION
A 75-year-old myasthenic patient, treated with prednisone and pyridostigmine, was diagnosed with invasive listeriosis. He presented with muscle weakness, dyspnea, hemiparesis and altered mental status. Brain imaging revealed multiple abscesses and blood cultures were positive for . Despite combination antibiotic therapy, he died 6 weeks after admission.
SYSTEMATIC REVIEW
Ninety-six cases of brain abscesses from 1968 to 2023 were reviewed; the majority of the patients were men, 54 years-old on average, and had at least one risk factor for invasive listeriosis. The mortality exceeded 22%. Blood cultures and CSF/abscess cultures were positive in only 79.2% and 54.6%, respectively. The most common therapeutic approach was a combination regimen that included amoxicillin or ampicillin. Only 8 patients underwent surgery, of which one died.
CONCLUSION
This case highlights the importance of as a cause of brain abscesses in populations at risk, including myasthenic patients. The challenge of diagnosing and treating this condition is aggravated by the paucity of literature and the high mortality rate.
PubMed: 38075415
DOI: 10.53854/liim-3104-16 -
Infection and Immunity Sep 2023Apolipoprotein E (ApoE) is a lipid transport protein that is hypothesized to suppress proinflammatory cytokine production, particularly after stimulation with Toll-like...
Apolipoprotein E (ApoE) is a lipid transport protein that is hypothesized to suppress proinflammatory cytokine production, particularly after stimulation with Toll-like receptor (TLR) ligands such as lipopolysaccharide (LPS). Studies using transgenic ApoE human replacement mice (APOE) expressing one of three different allelic variants suggest that there is a hierarchy in terms of responsiveness to proinflammatory stimuli such as APOE4/E4 > APOE3/E3 > APOE2/E2. In this study, we test the hypothesis that genotype can also predict susceptibility to infection with the facultative intracellular gram-positive bacterium . We found that bone-marrow-derived macrophages isolated from aged APOE4/E4 mice expressed elevated levels of nitric oxide synthase 2 and were highly resistant to infection with compared to APOE3/E3 and APOE2/E2 mice. However, we did not find statistically significant differences in cytokine or chemokine output from either macrophages or whole splenocytes isolated from APOE2/E2, APOE3/E3, or APOE4/E4 mice following infection. , overall susceptibility to foodborne listeriosis also did not differ by genotype in either young (2 mo old) or aged (15 mo old) C57BL/6 mice. However, we observed a sex-dependent susceptibility to infection in aged APOE2/E2 male mice and a sex-dependent resistance to infection in aged APOE4/E4 male mice that was not present in female mice. Thus, these results suggest that genotype does not play an important role in innate resistance to infection with but may be linked to sex-dependent changes that occur during immune senescence.
Topics: Animals; Female; Humans; Male; Mice; Apolipoprotein E2; Apolipoprotein E3; Apolipoprotein E4; Apolipoproteins E; Cytokines; Genotype; Listeria monocytogenes; Listeriosis; Mice, Inbred C57BL; Mice, Transgenic
PubMed: 37594272
DOI: 10.1128/iai.00251-23 -
International Journal of Molecular... Mar 2024() is a food-borne pathogenic bacteria that frequently contaminates animal-derived food and low-temperature preserved food. caused by its infection has a high...
() is a food-borne pathogenic bacteria that frequently contaminates animal-derived food and low-temperature preserved food. caused by its infection has a high mortality rate and poses a serious threat to human health. Therefore, it is crucial to establish a sensitive, rapid and easy-to-operate technique. In this study, a Recombinase Aided Amplification (RAA) assisted CRISPR/Cas12a (RAA-CRISPR/Cas12a) fluorescence platform was established for highly sensitive nucleic acid detection of . The established RAA-CRISPR/Cas12a showed high sensitivity and high specificity, with the sensitivity of 350 CFU/mL and 5.4 × 10 ng/μL for pure bacterial solution and genomic DNA, and good specificity for 5 strains of spp. and 14 strains of other common pathogenic bacteria. could be detected at an initial concentration of 2.3 CFU/25g within 2 h of enriching the beef in the food matrix, and this method could be applied to food samples that were easily contaminated with The results of RAA-CRISPR/Cas12a could be observed in 5 min, while the amplification was completed in 20-30 min. The speed and sensitivity of RAA-CRISPR/Cas12a were significantly higher than that of the national standard method. In conclusion, the RAA-CRISPR/Cas12a system established in this study has new application potential in the diagnosis of food-borne pathogens.
Topics: Animals; Cattle; Humans; Listeria monocytogenes; CRISPR-Cas Systems; Food Microbiology; Nucleic Acid Amplification Techniques; Recombinases; DNA
PubMed: 38542449
DOI: 10.3390/ijms25063477 -
Frontiers in Microbiology 2023is the etiologic agent of listeriosis, a foodborne disease that poses a threat to public health globally. Chicken meat exhibits heightened susceptibility to...
is the etiologic agent of listeriosis, a foodborne disease that poses a threat to public health globally. Chicken meat exhibits heightened susceptibility to contamination during butchery. The persistence of this pathogen in the slaughterhouse environment enables recurring contamination of meat products. This study aimed at identifying the sources and transmission routes of contamination within an abattoir where it was consistently detected for three consecutive years (2019-2021). Furthermore, the environmental factors aiding contamination along chicken processing lines were determined by surveying the microbiome within the facility. Samples collected in 2019 to 2021 were subjected to culture-dependent analysis to assess the prevalence, serotypes, and multi-locus sequence typing (MLST) of . Additionally, the specimens collected in 2021 underwent culture-independent analysis via real-time quantitative polymerase chain reaction (qPCR) and 16S rRNA gene amplicon sequencing to identify the contamination sources and characterize the entire microbial community within the slaughterhouse. was isolated only from the clean zone, where the final slaughtering stage occurs. Most strains isolated from the final carcasses showed the same genetic cluster as the isolate in the chilling water and were assigned to MLST profile ST3. Culture-independent qPCR confirmed contamination in all samples, excluding post-scalding carcasses, prewashed post-evisceration carcasses, and the bleeding areas. Consequently, qPCR enabled more comprehensive identification of contamination points than culture-dependent approaches. Moreover, 16S rRNA gene amplicon sequencing demonstrated that psychro-tolerant and spoilage-related bacteria with -like attributes exhibited enhanced viability in the clean zone and immersion-chilling water. Metagenomics-based source tracking analysis further revealed that the shackles and chilling waters represent predominant sources of cross-contamination between different slaughterhouse zones, whereas the grading and packaging workstations and chilling water in the clean zone were deemed crucial sources affecting final carcass contamination. Collectively, these findings demonstrate through culture-dependent and -independent methods that spreads along the slaughter line, contaminating the slaughterhouse. Moreover, by investigating changes in microbial community and bacterial flow along the slaughter line within the facility, the sources influencing carcass contamination can be effectively traced.
PubMed: 38098672
DOI: 10.3389/fmicb.2023.1282961 -
Journal of Infection and Public Health Apr 2024Food-borne pathogen Listeria monocytogenes is abundantly present in nature and accountable for sporadic and epidemic cases of listeriosis in humans. The objective of...
BACKGROUND
Food-borne pathogen Listeria monocytogenes is abundantly present in nature and accountable for sporadic and epidemic cases of listeriosis in humans. The objective of this study was to screen common food sources for L. monocytogenes using biochemical and molecular methods to detect and characterise its toxin genes as well as for biofilm formation.
METHODS
A total of 92 samples, comprising dairy and street food products, were randomly collected from various sources for this investigation. The collected samples were processed for biochemical and molecular methods to detect L. monocytogenes. Additionally, virulence factors associated genes, antibiogram profiles and biofilm formation related assays were determined.
RESULTS
L. monocytogenes presence was confirmed using molecular detection methods targeting prs and lmo1030 genes, along with MALDI-TOF MS. Following 16 S rRNA sequencing, the identified Listeria species were further categorised into two groups. L. monocytogenes was detected in two (2.17%) food samples tested (L-23 and L-74). Multiplex PCR indicated the presence of seven virulence-related genes in L. monocytogenes isolates, i.e., inlA, inlB, prfA, iap, actA, plcB, and hlyA. In addition, 17 antibiotics were tested, whereby two isolates showed resistance to clindamycin and azithromycin, while one isolate (L-74) was also resistant to nalidixic acid, co-trimoxazole, ampicillin, norfloxacin, and cefotaxime. L-23 and L-74 isolates showed biofilm formation, especially at pH 8.6 and 37°C.
CONCLUSIONS
Besides the demonstration of the presence of L. monocytogenes in some dairy and street food products, this study underscores the need to increase the standards of hygiene on the one hand and the importance of the surveillance of food-borne pathogens on the other.
Topics: Humans; Listeria monocytogenes; India; Listeriosis; Anti-Bacterial Agents; Virulence Factors; Food Microbiology
PubMed: 38479066
DOI: 10.1016/j.jiph.2024.02.014 -
Revista Argentina de Microbiologia 2023Listeria monocytogenes is an opportunistic foodborne pathogen. It can resist stress conditions by adapting through the production of biofilms, which represents a serious...
Listeria monocytogenes is an opportunistic foodborne pathogen. It can resist stress conditions by adapting through the production of biofilms, which represents a serious problem for the food industry. It is classified into 14 serotypes, although only four (1/2a, 1/2b, 1/2c, and 4b) account for 89.0-98.0% of listeriosis cases worldwide. The objective of this study was to detect and serotype L.monocytogenes isolated from different food matrices from processing plants in Argentina. In the period 2016-2021, 1832 samples (meat, ready-to-eat foods, ice cream, dairy foods, and frozen vegetables) were analyzed, of which 226 (12.34%) isolates compatible with L.monocytogenes were detected. At the same time, environmental and surface samplings were performed in processing plants for ready-to-eat foods, sausages and dairy products, where environmental contamination with L.monocytogenes was detected in numerous critical points of the process, yielding a positivity rate of 22.7%. The molecular analysis of serogroups was performed, where it was observed that serogroup IIb was the most frequent with 66.5% (n=107), and in descending order IIc with 22.3% (n=36), and IIa (n=9) and IVb (n=9) with 5.6%. The serogroup mostly isolated in environmental monitoring was IIb. This work highlights the importance of the detection and serotyping of L.monocytogenes for taking actionable measures and identifying outbreaks, and is the first study in Argentina to describe an extensive study in food matrices.
Topics: Listeria monocytogenes; Serotyping; Food Contamination; Food Microbiology; Argentina; Polymerase Chain Reaction
PubMed: 37479608
DOI: 10.1016/j.ram.2023.05.004 -
Journal of Veterinary Internal Medicine 2024Listeriosis is a severe foodborne infection caused by Listeria monocytogenes, an important foodborne pathogen of animals and humans. Listeriosis is a rare disease in...
BACKGROUND
Listeriosis is a severe foodborne infection caused by Listeria monocytogenes, an important foodborne pathogen of animals and humans. Listeriosis is a rare disease in cats.
OBJECTIVE
To describe the clinical, diagnostic imaging, histological, and microbiological features of L. monocytogenes-associated mesenteric lymphadenitis in a cat.
ANIMALS
Listeria monocytogenes-associated mesenteric lymphadenitis was confirmed in a cat by histology and microbiology.
RESULTS
Two distinct isolates of L. monocytogenes were cultured from the affected mesenteric lymph node and whole genome sequencing was performed.
CONCLUSION AND CLINICAL IMPORTANCE
This report should alert veterinary clinicians and microbiologists to the syndrome, which may have implications for health and food safety in animals and humans.
Topics: Humans; Cats; Animals; Listeria monocytogenes; Mesenteric Lymphadenitis; Food Microbiology; Listeriosis; Genomics; Cat Diseases
PubMed: 38051604
DOI: 10.1111/jvim.16961 -
Acta Crystallographica. Section D,... May 2024CdaA is the most widespread diadenylate cyclase in many bacterial species, including several multidrug-resistant human pathogens. The enzymatic product of CdaA, cyclic...
CdaA is the most widespread diadenylate cyclase in many bacterial species, including several multidrug-resistant human pathogens. The enzymatic product of CdaA, cyclic di-AMP, is a secondary messenger that is essential for the viability of many bacteria. Its absence in humans makes CdaA a very promising and attractive target for the development of new antibiotics. Here, the structural results are presented of a crystallographic fragment screen against CdaA from Listeria monocytogenes, a saprophytic Gram-positive bacterium and an opportunistic food-borne pathogen that can cause listeriosis in humans and animals. Two of the eight fragment molecules reported here were localized in the highly conserved ATP-binding site. These fragments could serve as potential starting points for the development of antibiotics against several CdaA-dependent bacterial species.
Topics: Listeria monocytogenes; Crystallography, X-Ray; Binding Sites; Bacterial Proteins; Models, Molecular; Dinucleoside Phosphates; Anti-Bacterial Agents; Humans; Phosphorus-Oxygen Lyases; Protein Conformation
PubMed: 38682668
DOI: 10.1107/S205979832400336X