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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 -
Animals : An Open Access Journal From... Dec 2023Small ruminants often suffer from central nervous system (CNS) disorders, and cerebrospinal fluid (CSF) analysis can be used as a diagnostic tool in this regard. In...
BACKGROUND
Small ruminants often suffer from central nervous system (CNS) disorders, and cerebrospinal fluid (CSF) analysis can be used as a diagnostic tool in this regard. In small animals and cattle, specific CSF patterns have been defined for specific disease categories. No data exist regarding CSF results obtained from small ruminants and their association with certain CNS diseases.
OBJECTIVES
The objective of this study was to retrospectively investigate CSF findings obtained from sheep and goats and to identify possible CSF patterns associated with disease categories.
METHODS
CSF samples and medical records from 44 sheep and 27 goats were included in this study. All animals were presented to the Veterinary Teaching Hospital Zurich of the Veterinary Teaching Hospital Zurich of the Vetsuisse Faculty of the University of Zurich between 2003 and 2016 and had either a confirmed CNS diagnosis or showed CSF changes without a specific CNS diagnosis.
RESULTS
Mixed mononuclear pleocytosis was the most common CSF pattern in sheep (25%), followed by monocytic pleocytosis (21%). Lymphocytic pleocytosis was most frequently found in goats (37%). In 75% of sheep and 56% of goats, infectious CNS diseases were diagnosed, with listeriosis being the most common infectious disease in both species, followed by parasitic disorders (nematodiasis and coenurosis).
CONCLUSIONS
The cytologic CSF patterns in small ruminants are mainly based on the increased presence of monocytic and lymphocytic cells with variable quantitative expression, whereas neutrophilic pleocytosis and cytoalbuminologic dissociation were rare findings. Infectious diseases of bacterial origin were the most common underlying causes for CSF alterations in sheep and goats, followed by parasitic disorders. The pleocytosis type is not helpful for differentiating disease types.
PubMed: 38200777
DOI: 10.3390/ani14010046 -
Foods (Basel, Switzerland) Nov 2023In recent years, essential oils (EOs) have received interest due to their antibacterial properties. Accordingly, the present study aimed to investigate the effectiveness...
In recent years, essential oils (EOs) have received interest due to their antibacterial properties. Accordingly, the present study aimed to investigate the effectiveness of the EOs obtained from seven species of on three strains of (two serotyped wild strains and one ATCC strain), a bacterium able to contaminate food products and cause foodborne disease in humans. The species analysed in the present study were cultivated at the Botanic Garden and Museum of the University of Pisa, and their air-dried aerial parts were subjected to hydrodistillation using a Clevenger apparatus. The obtained EOs were analysed via gas chromatography coupled with mass spectrometry for the evaluation of their chemical composition, and they were tested for their inhibitory and bactericidal activities by means of MIC and MBC. The tested Eos showed promising results, and the best outcomes were reached by EO, showing an MIC of 1:256 and an MBC of 1:64. The predominant compounds of this EO were the sesquiterpenes caryophyllene oxide and β-caryophyllene, together with the monoterpenes bornyl acetate and borneol. These results suggest that these EOs may possibly be used in the food industry as preservatives of natural origins.
PubMed: 38231686
DOI: 10.3390/foods12234235 -
Nature Communications Oct 2023Listeriosis is one of the most serious foodborne diseases caused by the intracellular bacterium Listeria monocytogenes. Its two major virulence factors, broad-range...
Listeriosis is one of the most serious foodborne diseases caused by the intracellular bacterium Listeria monocytogenes. Its two major virulence factors, broad-range phospholipase C (LmPC-PLC) and the pore-forming toxin listeriolysin O (LLO), enable the bacterium to spread in the host by destroying cell membranes. Here, we determine the crystal structure of LmPC-PLC and complement it with the functional analysis of this enzyme. This reveals that LmPC-PLC has evolved several structural features to regulate its activity, including the invariant position of the N-terminal tryptophan (W1), the structurally plastic active site, Zn-dependent activity, and the tendency to form oligomers with impaired enzymatic activity. We demonstrate that the enzymatic activity of LmPC-PLC can be specifically inhibited by its propeptide added in trans. Furthermore, we show that the phospholipase activity of LmPC-PLC facilitates the pore-forming activity of LLO and affects the morphology of LLO oligomerization on lipid membranes, revealing the multifaceted synergy of the two virulence factors.
Topics: Humans; Listeria monocytogenes; Type C Phospholipases; Listeriosis; Hemolysin Proteins; Cell Membrane; Virulence Factors
PubMed: 37838694
DOI: 10.1038/s41467-023-42134-4 -
Life (Basel, Switzerland) Nov 2023of the phylogenetic lineage II (PLII) are common in the European environment and are hypovirulent. Despite this, they caused more than a third of the sporadic cases of...
of the phylogenetic lineage II (PLII) are common in the European environment and are hypovirulent. Despite this, they caused more than a third of the sporadic cases of listeriosis and multi-country foodborne outbreaks. ST37 is one of them. During the COVID-19 pandemic, ST37 appeared in clinical cases and ranked second in occurrence among food isolates in the Moscow region. The aim of this study was to describe the genomic features of ST37 isolates from different sources. All clinical cases of ST37 were in the cohort of male patients (age, 48-81 years) with meningitis-septicemia manifestation and COVID-19 or Influenza in the anamnesis. The core genomes of the fish isolates were closely related. The clinical and meat isolates revealed a large diversity. Prophages (2-4/genome) were the source of the unique genes. Two clinical isolates displayed pseudolysogeny, and excided prophages were A006-like. In the absence of plasmids, the assortment of virulence factors and resistance determinants in the chromosome corresponded to the hypovirulent characteristics. However, all clinical isolates caused severe disease, with deaths in four cases. Thus, these studies allow us to speculate that a previous viral infection increases human susceptibility to listeriosis.
PubMed: 38004307
DOI: 10.3390/life13112167 -
Foods (Basel, Switzerland) Jan 2024A review of the published quantitative risk assessment (QRA) models of in meat and meat products was performed, with the objective of appraising the intervention... (Review)
Review
A review of the published quantitative risk assessment (QRA) models of in meat and meat products was performed, with the objective of appraising the intervention strategies deemed suitable for implementation along the food chain as well as their relative effectiveness. A systematic review retrieved 23 QRA models; most of them (87%) focused on ready-to-eat meat products and the majority (78%) also covered short supply chains (end processing/retail to consumption, or consumption only). The processing-to-table scope was the choice of models for processed meats such as chorizo, bulk-cooked meat, fermented sausage and dry-cured pork, in which the effects of processing were simulated. Sensitivity analysis demonstrated the importance of obtaining accurate estimates for lag time, growth rate and maximum microbial density, in particular when affected by growth inhibitors and lactic acid bacteria. In the case of deli meats, QRA models showed that delicatessen meats sliced at retail were associated with a higher risk of listeriosis than manufacture pre-packed deli meats. Many models converged on the fact that (1) controlling cold storage temperature led to greater reductions in the final risk than decreasing the time to consumption and, furthermore, that (2) lower numbers and less prevalence of at the end of processing were far more effective than keeping low temperatures and/or short times during retail and/or home storage. Therefore, future listeriosis QRA models for meat products should encompass a processing module in order to assess the intervention strategies that lead to lower numbers and prevalence, such as the use of bio-preservation and novel technologies. Future models should be built upon accurate microbial kinetic parameters, and should realistically represent cross-contamination events along the food chain.
PubMed: 38338495
DOI: 10.3390/foods13030359 -
Microorganisms Aug 2023is an important pathogen that can cause listeriosis. Despite the growing recognition of spp. as a foodborne and environmental pathogen, the understanding of its...
is an important pathogen that can cause listeriosis. Despite the growing recognition of spp. as a foodborne and environmental pathogen, the understanding of its prevalence and characteristics of spp. in the marine environment remains unknown. In this study, we first investigated the genetic and phenotypic characteristics of species isolated in a coastal city in China. The findings revealed that the sequence type 87 (ST87) , a prevalent clinical and seafood strain in China, dominates in recreational beach sands and possesses a notable biofilm-forming capacity in seawater. The presence of ST87 in coastal environments indicates the potential health risks for both recreational activities and seafood consumption. Moreover, the ST121 isolates from sand had a versatile plasmid encoding multifunctional genes, including for UV resistance, for salt resistance, and for oxidative resistance and multiple transposases, which potentially aid in survival under natural environments. Black-headed gulls potentially facilitate the spread of , with similar ST35 strains found in gulls and beach sand. As a reservoir of microbes from marine environments and human/animal excrement, coastal sand would play an important role in the spread of and is an environmental risk for human listeriosis.
PubMed: 37764010
DOI: 10.3390/microorganisms11092166 -
Frontiers in Cellular and Infection... 2023() is associated with severe foodborne infections and ubiquitous in the nature. Identification of characteristics of transmission through trading of food products is...
() is associated with severe foodborne infections and ubiquitous in the nature. Identification of characteristics of transmission through trading of food products is essential for rapidly tracking sources and controlling dissemination of listeriosis. In this study, a total of 44 strains were isolated from food products originating from 14 countries/regions during 2003-2018 at the Shanghai port. The genomes of these Lm strains were sequenced by high-throughput sequencing. Multilocus sequence typing (MLST) analysis showed that 43 isolates were divided into 17 sequence types (STs). The distribution of STs was decentralized, with the dominant ST2 accounting for only 18.18% of the strains. The LM63 strain did not match with any of the existing STs. Core-genome MLST (cgMLST) analysis based on 1748 core genes categorized the 44 strains into 30 cgMLST types (CTs), with CT10153 and CT7892 as the most predominant CTs. Notably, LM63 and LM67 shared the same CT in the cgMLST analysis. The phylogenetic analysis based on single-copy homologous genes revealed that the 44 strains were primarily classified into two lineages. The SNP analysis also indicated that these strains were roughly divided into two clades, with strains in the first clade mainly collected earlier than those in the second clade, which were predominantly collected from 2010 onwards. The analysis using the virulence factor database (VFDB) indicated that the virulence gene was the most prevalent among these 44 strains. Notably, , , and were enriched in this dataset, requiring further clarification of their roles in through future studies. These results might provide a clue for understanding of the global epidemiology and surveillance of and present insights for implementing effective measures to reduce or prevent contamination outbreaks in imported food products.
Topics: Humans; Listeria monocytogenes; Multilocus Sequence Typing; Phylogeny; Food Microbiology; China; Listeriosis
PubMed: 38179422
DOI: 10.3389/fcimb.2023.1287564 -
Microorganisms Aug 2023Probiotics for humans and direct-fed microbials for livestock are increasingly popular dietary ingredients for supporting immunity. The aim of this study was to...
Probiotics for humans and direct-fed microbials for livestock are increasingly popular dietary ingredients for supporting immunity. The aim of this study was to determine the effects of dietary supplementation of MB40 (MB40) on immunity in piglets challenged with the foodborne pathogen (LM). Three-week-old piglets ( = 32) were randomly assigned to four groups: (1) basal diet, (2) basal diet with LM challenge, (3) MB40-supplemented diet, and (4) MB40-supplemented diet with LM challenge. Experimental diets were provided throughout a 14-day (d) period. On d8, piglets in groups 2 and 4 were intraperitoneally inoculated with LM at 10 CFU/mL per piglet. Blood samples were collected at d1, d8, and d15 for biochemical and immune response profiling. Animals were euthanized and necropsied at d15 for liver and spleen bacterial counts and intestinal morphological analysis. At d15, LM challenge was associated with increased spleen weight ( = 0.017), greater circulating populations of neutrophils ( = 0.001) and monocytes ( = 0.008), and reduced ileal villus height to crypt depth ratio ( = 0.009), compared to non-challenged controls. MB40 supplementation reduced LM bacterial counts in the liver and spleen by 67% ( < 0.001) and 49% ( < 0.001), respectively, following the LM challenge, compared to the basal diet. MB40 supplementation was also associated with decreased circulating concentrations of monocytes ( = 0.007). Altogether, these data suggest that MB40 supplementation is a safe and well-tolerated approach to enhance immunity during systemic infection.
PubMed: 37630670
DOI: 10.3390/microorganisms11082110 -
BMC Infectious Diseases May 2024We report a very rare case of Listeria multiple brain abscesses manifested as delirium, which represented diagnostic and therapeutic challenges overcome only by the...
We report a very rare case of Listeria multiple brain abscesses manifested as delirium, which represented diagnostic and therapeutic challenges overcome only by the close cooperation between Infectious Diseases and Neuroradiology, without which a satisfactory outcome would not be achieved.An elderly man presented with confusion and drowsiness with a background of type-II diabetes mellitus. Although computed tomography of the brain only showed frontal lobe oedema, contrast magnetic resonance (MR) imaging showed numerous irregular rim-enhancing lesions containing central diffusion restriction, suggesting multiple pyogenic cerebral abscesses of unclear aetiology. Thereafter, Listeria monocytogenes was isolated from blood cultures, suggesting this as the causative organism. Deemed unsuitable for neurosurgical drainage, the patient received medical management with a protracted course of antibiotics. This case was extremely challenging, due to 1) the impossibility of source control, 2) the small number of effective antibiotics available to treat this condition, and 3) the inevitable antibiotic side-effects, derived from long-term exposure. A successful outcome was only possible thanks to strict close multidisciplinary follow up, requiring frequent MR imaging and a judicious antibiotic choice, including monitoring of their side-effects. Due to the rarity of this condition, there is lack of guidance on its management, hence the importance of multidisciplinary involvement with very close imaging and antibiotic monitoring.
Topics: Humans; Male; Brain Abscess; Listeriosis; Anti-Bacterial Agents; Listeria monocytogenes; Aged; Magnetic Resonance Imaging; Tomography, X-Ray Computed; Brain; Delirium
PubMed: 38720244
DOI: 10.1186/s12879-024-09295-z