Medical students are exposed to the hospital environment and patients during their studies, increasing the risk of exposure to virulent and antibiotic-resistant isolates of Staphylococcus aureus. The aim of the study is to determine the prevalence of Staphylococcus aureus among medical students who have varying levels of exposure to the hospital environment to provide valuable insights into the risk of colonization and transmission. Nasal swabs and fingerprints were obtained and cultured on a selective medium for staphylococci. The obtained isolates were confirmed as methicillin-sensitive S. aureus (MSSA) or methicillin-resistant (MRSA) using PCR. Antibiotic resistance, the presence of virulence genes including enterotoxin encoding genes, and spa typing were performed. Among pre-clinical students, MSSA was detected on the nose in 45.2% and on the fingerprints in 10.6% of the participants. Among clinical students, MSSA was detected on the nose in 42.0% and on the fingerprints in 25.4%. Only one MRSA isolate was obtained. Genes seg and sei were the most frequently detected in both student groups, with their presence in over 40% of isolates among clinical students. The eta and etb genes were mainly detected from the nose in both student groups. In pre-clinical students, S. aureus carrying eta gene occurred in 6.4% and etb in 8.5%. In clinical students, the occurrence was 5.1% for eta and 8.5% for etb. The tst gene was identified only in the nose and fingerprints of the clinical student group. The most frequently observed resistance was to clindamycin and erythromycin. In total 58 different spa types were identified. High rates of asymptomatic MSSA carriage were observed in both groups of medical students. Detected MSSA strains showed a high degree of genetic variability, with a number of them carrying the virulence and antibiotic resistance genes. Although students do not exhibit increased risk to their patient's, increased hygiene is required in asymptomatic carriage personnel. The overall prevalence of MRSA was low, with a minimal risk of spread.
- MeSH
- Anti-Bacterial Agents pharmacology MeSH
- Adult MeSH
- Virulence Factors * genetics MeSH
- Humans MeSH
- Methicillin-Resistant Staphylococcus aureus genetics isolation & purification drug effects classification MeSH
- Microbial Sensitivity Tests MeSH
- Young Adult MeSH
- Carrier State * microbiology epidemiology MeSH
- Prevalence MeSH
- Staphylococcal Infections * microbiology epidemiology MeSH
- Staphylococcus aureus * genetics isolation & purification drug effects classification MeSH
- Students, Medical * MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Young Adult MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
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- MeSH
- Exfoliatins isolation & purification adverse effects MeSH
- Leukocidins isolation & purification adverse effects MeSH
- Humans MeSH
- Polymerase Chain Reaction MeSH
- Shock, Septic etiology MeSH
- Staphylococcal Infections * mortality MeSH
- Staphylococcus aureus * isolation & purification classification MeSH
- Check Tag
- Humans MeSH
- Geographicals
- Czech Republic MeSH
Národní referenční laboratoř pro stafylokoky CEM SZÚ se i v roce 2021, v rámci zajištění surveillance stafylokokových infekcí, věnovala podrobnému vyšetřování kmenů stafylokoků z humánního klinického materiálu. Celkem to bylo 659 kmenů, převážně druhu Staphylococcus aureus, které byly zaslány asi z 90 bakteriologických pracovišť z celé České republiky. Metodou PCR byla zjišťována přítomnost genů kódujících především Pantonův - Valentinův leukocidin, toxin Syndromu toxického šoku, exfoliatiny A, B, D a enterotoxiny A–D. Informace o produkci faktorů virulence jsou důležité pro ošetřující lékaře ke správnému stanovení klinické diagnózy a tedy i vhodné terapie. V roce 2021 jsme zaregistrovali 13 případů závažného onemocnění - syndrom toxického šoku, kdy jsme mohli potvrdit původce – toxinogenní kmen S. aureus. Pomohli jsme řešit i hromadný výskyt puchýřnatého onemocnění novorozenců v jedné porodnici, kdy byl příčinou kmen S. aureus s produkcí exfoliatinu A. V celém souboru bylo i 45 (5,9 %) kmenů koaguláza negativních stafylokoků. U těchto podmíněných patogenů jsme fenotypizací a metodou hmotnostní spektrometrie kmeny identifikovali, resp. konfirmovali identifikaci zjištěnou již v terénních laboratořích.
The main focus of the National Reference Laboratory for Staphylococci (NRL) in 2020 was again on the investigation of staphylococcal strains from human clinical specimens within the surveillance of staphylococcal infections. In total, 659 strains mostly of the species Staphylococcus aureus referred to the NRL by 90 bacteriological laboratories from all over the Czech Republic were analysed. The strains were screened by PCR for the genes encoding Panton-Valentine leukocidin, toxic shock syndrome toxin, exfoliative toxins A, B, and D, and enterotoxins A–D. Data on the production of virulence factors are helpful for attending physicians in determining the right diagnosis and effective treatment. In 2021, 13 cases of severe toxic shock syndrome were reported, with toxigenic strain of S. aureus being confirmed as the causative agent. The NRL also participated in the investigation of an outbreak of blistering skin condition in newborns in one maternity hospital where the cause of infection was an exfoliative toxin A producing strain of S. aureus. Fifty-eight strains (5.9%) referred to the NRL were coagulase-negative staphylococci. These opportunistic pathogens were identified or confirmed, after previous identification by field laboratories, by phenotyping and mass spectrometry.
- MeSH
- Enterotoxins isolation & purification adverse effects MeSH
- Exfoliatins isolation & purification adverse effects MeSH
- Coagulase isolation & purification MeSH
- Leukocidins isolation & purification adverse effects MeSH
- Humans MeSH
- Microbiological Techniques MeSH
- Shock, Septic epidemiology etiology classification MeSH
- Staphylococcal Infections * epidemiology mortality pathology prevention & control MeSH
- Staphylococcus aureus isolation & purification classification pathogenicity MeSH
- Staphylococcus isolation & purification classification pathogenicity MeSH
- Statistics as Topic MeSH
- Check Tag
- Humans MeSH
- Geographicals
- Czech Republic MeSH
Staphylococcus aureus is a major bacterial human pathogen that causes a wide variety of clinical manifestations. The main aim of the presented study was to determine and optimize a novel sequencing independent approach that enables molecular typing of S. aureus isolates and elucidates the transmission of emergent clones between patients. In total, 987 S. aureus isolates including both methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) isolates were used to evaluate the novel typing approach combining high-resolution melting (HRM) analysis of multilocus sequence typing (MLST) genes (mini-MLST) and spa gene (spa-HRM). The novel approach's discriminatory ability was evaluated by whole-genome sequencing (WGS). The clonal relatedness of tested isolates was set by the BURP and BURST approach using spa and MLST data, respectively. Mini-MLST classified the S. aureus isolates into 38 clusters, followed by spa-HRM classifying the isolates into 101 clusters. The WGS proved HRM-based methods to effectively differentiate between related S. aureus isolates. Visualizing evolutionary relationships among different spa-types provided by the BURP algorithm showed comparable results to MLST/mini-MLST clonal clusters. We proved that the combination of mini-MLST and spa-HRM is rapid, reproducible, and cost-efficient. In addition to high discriminatory ability, the correlation between spa evolutionary relationships and mini-MLST clustering allows the variability in population structure to be monitored. IMPORTANCE Rapid and cost-effective molecular typing tools for Staphylococcus aureus epidemiological applications such as transmission tracking, source attribution and outbreak investigations are highly desirable. High-resolution melting based methods are effective alternative to those based on sequencing. Their good reproducibility and easy performance allow prospective typing of large set of isolates while reaching great discriminatory power. In this study, we established a new epidemiological approach to S. aureus typing. This scheme has the potential to greatly improve epidemiological investigations of S. aureus.
- MeSH
- Infection Control * MeSH
- Humans MeSH
- Methicillin-Resistant Staphylococcus aureus genetics isolation & purification MeSH
- Molecular Typing methods MeSH
- Multilocus Sequence Typing MeSH
- Prospective Studies MeSH
- Reproducibility of Results MeSH
- Whole Genome Sequencing MeSH
- Staphylococcal Infections diagnosis microbiology MeSH
- Staphylococcus aureus classification genetics isolation & purification MeSH
- Bacterial Typing Techniques methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Staphylococcus aureus (S. aureus) is an important causative agent of contagious intermammary infections in dairy cattle. S. aureus is also considered as an important foodborne pathogen and cause of food poisoning cases and outbreaks worldwide. In order to understand the molecular ecology of S. aureus, the present study compared phenotypic and genotypic characteristics of 70 S. aureus isolates from bovine mastitis milk samples collected during the period from August 2001 to March 2014 in different regions of Northern Germany. The S. aureus isolates were characterised phenotypically, as well as genotypically for their genetic diversity using multi-locus sequence typing (MLST), spa typing and the presence of virulence genes encoding 16 staphylococcal enterotoxins (sea-selu), toxic shock syndrome toxin (tst), thermonuclease (nuc), clumping factor (clfA and clfB), coagulase (coa) and the methicillin resistance gene mecA. A total of 16 sequence types were grouped into eight clonal complexes (CCs), and 17 spa types were identified. These included six novel sequence types and one novel spa type. The majority of bovine mastitis milk-associated sequence types belonged to the clonal complex CC5, CC97, CC133, and CC151 and showed closely related genotypes or lineages with sequence types of human origin. The genotype CC133 (ST133-t1403) was predominant, constituting 27.1% of the isolates. In addition, the S. aureus isolates displayed nine different enterotoxigenic profiles. All S. aureus were methicillin-susceptible (MSSA). The current study provides new information on phenotypic and genotypic traits of S. aureus isolates from bovine mastitis. The comparison of characteristics of isolates from the present study originating from mastitis milk showed similarities with human isolates. This might help to better understand the distribution of S. aureus in the one health context.
- MeSH
- Genes, Bacterial genetics MeSH
- Drug Resistance, Bacterial genetics MeSH
- Bacterial Proteins MeSH
- Enterotoxins genetics MeSH
- Virulence Factors genetics MeSH
- Phenotype MeSH
- Genotype MeSH
- Humans MeSH
- Mastitis, Bovine microbiology MeSH
- Milk microbiology MeSH
- Multilocus Sequence Typing MeSH
- Food Microbiology MeSH
- Penicillin-Binding Proteins deficiency MeSH
- Cattle MeSH
- Staphylococcal Infections microbiology MeSH
- Staphylococcus aureus classification genetics isolation & purification MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Cattle MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Germany MeSH
Morel's disease is a form of abscessing lymphadenitis of sheep and goats caused by Staphylococcus aureus subspecies anaerobius. In Europe and Africa, the disease is linked to S. aureus of multilocus sequence type 1464. In an outbreak recorded in 2015 in a flock of 530 animals in the district of Nymburk, Czech Republic, Europe, the causative agent was cultured and subsequently confirmed by Maldi-TOF. Neither antibiotic therapy nor surgical interventions met any success, although the strain isolated was found to be sensitive to antibiotics used. Vaccination and revaccination with inactivated autogenous vaccine administered subcutaneously was relatively successful. Subsequent multilocus sequence typing revealed the presence of new S. aureus sequence type 3756, different from 1464 in three out of seven genes typed. The isolate thus represents a new sequence type of Staphylococcus aureus ssp. anaerobius which should be considered as a causative agent of Morel's disease.
- MeSH
- Anti-Bacterial Agents therapeutic use MeSH
- Lymphadenitis drug therapy microbiology veterinary MeSH
- Microbial Sensitivity Tests MeSH
- Multilocus Sequence Typing MeSH
- Sheep Diseases drug therapy microbiology MeSH
- Sheep MeSH
- Staphylococcal Infections drug therapy microbiology veterinary MeSH
- Staphylococcal Vaccines immunology MeSH
- Staphylococcus aureus classification immunology isolation & purification MeSH
- Vaccination MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
Laboratory mice are the most commonly used animal model for Staphylococcus aureus infection studies. We have previously shown that laboratory mice from global vendors are frequently colonized with S. aureus. Laboratory mice originate from wild house mice. Hence, we investigated whether wild rodents, including house mice, as well as shrews are naturally colonized with S. aureus and whether S. aureus adapts to the wild animal host. 295 animals of ten different species were caught in different locations over four years (2012-2015) in Germany, France and the Czech Republic. 45 animals were positive for S. aureus (15.3%). Three animals were co-colonized with two different isolates, resulting in 48 S. aureus isolates in total. Positive animals were found in Germany and the Czech Republic in each studied year. The S. aureus isolates belonged to ten different spa types, which grouped into six lineages (clonal complex (CC) 49, CC88, CC130, CC1956, sequence type (ST) 890, ST3033). CC49 isolates were most abundant (17/48, 35.4%), followed by CC1956 (14/48, 29.2%) and ST890 (9/48, 18.8%). The wild animal isolates lacked certain properties that are common among human isolates, e.g., a phage-encoded immune evasion cluster, superantigen genes on mobile genetic elements and antibiotic resistance genes, which suggests long-term adaptation to the wild animal host. One CC130 isolate contained the mecC gene, implying wild rodents might be both reservoir and vector for methicillin-resistant . In conclusion, we demonstrated that wild rodents and shrews are naturally colonized with S. aureus, and that those S. aureus isolates show signs of host adaptation.
- MeSH
- Anti-Bacterial Agents pharmacology MeSH
- Bacterial Proteins genetics MeSH
- Animals, Wild microbiology MeSH
- Virulence Factors genetics MeSH
- Rodentia microbiology MeSH
- Methicillin-Resistant Staphylococcus aureus MeSH
- Microbial Sensitivity Tests MeSH
- Mice MeSH
- Shrews microbiology MeSH
- Staphylococcal Infections epidemiology veterinary MeSH
- Staphylococcus aureus classification isolation & purification MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
- France MeSH
- Germany MeSH
Exfoliative toxin B (ETB) encoded by some large plasmids plays a crucial role in epidermolytic diseases caused by Staphylococcus aureus. We have found as yet unknown types of etb gene-positive plasmids isolated from a set of impetigo strains implicated in outbreaks of pemphigus neonatorum in Czech maternity hospitals. Plasmids from the strains of clonal complex CC121 were related to archetypal plasmid pETBTY4. Sharing a 33-kb core sequence including virulence genes for ETB, EDIN C, and lantibiotics, they were assigned to a stand-alone lineage, named pETBTY4-based plasmids. Differing from each other in the content of variable DNA regions, they formed four sequence types. In addition to them, a novel unique plasmid pETB608 isolated from a strain of ST130 was described. Carrying conjugative cluster genes, as well as new variants of etb and edinA genes, pETB608 could be regarded as a source of a new lineage of ETB plasmids. We have designed a helpful detection assay, which facilitates the precise identification of the all described types of ETB plasmids.
- MeSH
- Bacterial Proteins genetics MeSH
- Bacteriocins genetics MeSH
- Dermotoxins genetics MeSH
- DNA, Bacterial genetics MeSH
- Exfoliatins genetics MeSH
- Phylogeny MeSH
- Impetigo epidemiology microbiology MeSH
- Humans MeSH
- Pemphigus epidemiology microbiology MeSH
- Plasmids genetics isolation & purification MeSH
- Whole Genome Sequencing MeSH
- Staphylococcus aureus classification genetics MeSH
- Virulence genetics MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic epidemiology MeSH
The methicillin-resistant Staphylococcus aureus causes difficult-to-treat healthcare-associated infections in humans. For fast and effective selection of an appropriate antibiotic therapy, it is essential to have rapid and reliable methods for differentiation of methicillin-resistant S. aureus from less dangerous methicillin-sensitive S. aureus. There have been many methods for the identification of methicillin-resistant S. aureus described but none has been accepted as an international standard. The most commonly used techniques such as phenotyping and genotyping have a few disadvantages, for instance, these techniques are not reproducible and stable. In addition, they are time-consuming, expensive, and they are not capable to distinguish all S. aureus strains. In this study, the methicillin-resistant and methicillin-sensitive S. aureus isolates obtained from patients were extracted in hot water. The released proteins were characterised by sodium dodecyl sulphate polyacrylamide gel electrophoresis and gel isoelectric focusing. These two methods were able to differentiate among tested bacterial strains. The proposed methods are time saving, they are applicable in standard biochemical laboratories, and they do not require any expensive equipment.
- MeSH
- Bacteriological Techniques methods MeSH
- Time Factors MeSH
- Electrophoresis, Polyacrylamide Gel methods MeSH
- Isoelectric Focusing methods MeSH
- Humans MeSH
- Methicillin Resistance * MeSH
- Staphylococcus aureus chemistry classification MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Evaluation Study MeSH
- Research Support, Non-U.S. Gov't MeSH
Sublethal concentrations (sub-MICs) of certain disinfectants are no longer effective in removing biofilms from abiotic surfaces and can even promote the formation of biofilms. Bacterial cells can probably adapt to these low concentrations of disinfectants and defend themselves by way of biofilm formation. In this paper, we report on three Staphylococcus aureus biofilm formers (strong B+++, moderate B++, and weak B+) that were cultivated with sub-MICs of commonly used disinfectants, ethanol or chloramine T, and quantified using Syto9 green fluorogenic nucleic acid stain. We demonstrate that 1.25-2.5% ethanol and 2500 μg/mL chloramine T significantly enhanced S. aureus biofilm formation. To visualize differences in biofilm compactness between S. aureus biofilms in control medium, 1.25% ethanol, or 2500 μg/mL chloramine T, scanning electron microscopy was used. To describe changes in abundance of surface-exposed proteins in ethanol- or chloramine T-treated biofilms, surface proteins were prepared using a novel trypsin shaving approach and quantified after dimethyl labeling by LC-LTQ/Orbitrap MS. Our data show that some proteins with adhesive functions and others with cell maintenance functions and virulence factor EsxA were significantly upregulated by both treatments. In contrast, immunoglobulin-binding protein A was significantly downregulated for both disinfectants. Significant differences were observed in the effect of the two disinfectants on the expression of surface proteins including some adhesins, foldase protein PrsA, and two virulence factors.
- MeSH
- Bacterial Proteins metabolism MeSH
- Biofilms drug effects growth & development MeSH
- Disinfectants administration & dosage MeSH
- Species Specificity MeSH
- Membrane Proteins metabolism MeSH
- Food Microbiology * MeSH
- Gene Expression Regulation, Bacterial drug effects physiology MeSH
- Staphylococcus aureus classification drug effects metabolism MeSH
- Cell Survival drug effects MeSH
- Dose-Response Relationship, Drug MeSH
- Publication type
- Journal Article MeSH
