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"Vogel, Ulrich"
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Faecal carriage of CTX-M extended-spectrum beta-lactamase-producing Enterobacteriaceae among street children dwelling in Mwanza city, Tanzania
2017
Data on ESBL carriage of healthy people including children are scarce especially in developing countries. We analyzed the prevalence and genotypes of ESBL-producing Enterobacteriaceae (EPE) in Tanzanian street children with rare contact to healthcare facilities but significant interactions with the environment, animals and other people.
Between April and July 2015, stool samples of 107 street children, who live in urban Mwanza were analyzed for EPE. Intestinal carriage of EPE was found in 34 (31.8%, 95% CI; 22.7-40.3) children. Of the 36 isolates from 34 children, 30 (83.3%) were Escherichia coli (E. coli) and six Klebsiella pneumoniae (K. pneumoniae). Out of 36 isolates, 36 (100%), 35 (97%), 25 (69%) and 16 (44%) were resistant to tetracycline, trimethoprim-sulfamethoxazole, ciprofloxacin and gentamicin, respectively. Beta-lactamase genes and the multilocus sequence types of E. coli and K. pneumoniae were characterized. ESBL gene blaCTX-M-15 was detected in 75% (27/36) of ESBL isolates. Sequence types (STs) 131, 10, 448 and 617 were the most prevalent in E. coli. Use of local herbs (OR: 3.5, 95% CI: 1.51-8.08, P = 0.003) and spending day and night on streets (OR: 3.6, 95% CI: 1.44-8.97, P = 0.005) were independent predictors of ESBL carriage.
We observed a high prevalence of blaCTX-M-15 in EPE collected from street children in Tanzania. Detection of E. coli STs 131, 10, 38 and 648, which have been observed worldwide in animals and people, highlights the need for multidisciplinary approaches to understand the epidemiology and drivers of antimicrobial resistance in low-income countries.
Journal Article
Hospital preparedness for mass critical care during SARS-CoV-2 pandemic
by
Ertl, Georg
,
Franke, Axel
,
Kolibay, Felix
in
Clinical decision making
,
Coronavirus Infections - epidemiology
,
Coronavirus Infections - therapy
2020
Mass critical care caused by the severe acute respiratory syndrome corona virus 2 pandemic poses an extreme challenge to hospitals. The primary goal of hospital disaster preparedness and response is to maintain conventional or contingency care for as long as possible. Crisis care must be delayed as long as possible by appropriate measures. Increasing the intensive care unit (ICU) capacities is essential. In order to adjust surge capacity, the reduction of planned, elective patient care is an adequate response. However, this involves numerous problems that must be solved with a sense of proportion. This paper summarises preparedness and response measures recommended to acute care hospitals.
Journal Article
Risk of Invasive Meningococcal Disease in Men Who Have Sex with Men: Lessons Learned from an Outbreak in Germany, 2012—2013
by
Vogel, Ulrich
,
Claus, Heike
,
Schink, Susanne
in
Acquired immune deficiency syndrome
,
Adolescent
,
Adult
2016
We undertook investigations in response to an invasive meningococcal disease (IMD) outbreak in men who have sex with men (MSM) in Berlin 2012-2013 to better understand meningococcal transmission and IMD risk in MSM.
We retrospectively searched for further IMD cases in MSM in Germany through local health departments and undertook exploratory interviews. We performed antigen sequence typing, characterized fHbp and aniA genes of strains with the outbreak finetype and reviewed epidemiologically or spatiotemporally linked cases from 2002-2014.
Among the 148 IMD-cases notified from 01.01.2012-30.09.2013 in 18-59 year-old men we identified 13 MSM in 6 federal states: 11 serogroup C (MenC, all finetype C:P1.5-1,10-8:F3-6), 2 MenB. Interviews with 7 MSM revealed frequent meeting of multiple partners online or via mobile apps and illicit drug use as potential risk factors. MenC incidence was 13-fold higher in MSM than non-MSM. MenC isolates from 9/11 MSM had a novel fHbp allele 766. All C:P1.5-1,10-8:F3-6 strains from MSM versus 16/23 from non-MSM had intact aniA genes (p = 0.04). Although definitive evidence for transmission among MSM in epidemiological or spatiotemporal clusters in 2002-2014 was lacking, clusters were more frequent in men aged 20-49 years. Molecular analysis of C:P1.5-1,10-8:F3-6 strains revealed cases with intact aniA since 2007, mainly associated with fHbp361, fHbp766 and fHbp813, all involving one or more MSM.
MenC incidence was elevated in MSM during the study period. Multiple casual sexual contacts and illicit drug use were common in affected MSM. In all strains from MSM we detected an intact aniA gene coding for a nitrite reductase, which permits survival in microanaerobic environments and could play a role in meningococcal transmission in MSM through urogenital colonization. Furthermore, meningococcal transmission among MSM may be sustained over large areas and thus require modified spatiotemporal scanning algorithms for timely detection and control.
Journal Article
Predicted strain coverage of a meningococcal multicomponent vaccine (4CMenB) in Europe: a qualitative and quantitative assessment
by
Ledroit, Morgan
,
Comanducci, Maurizio
,
Vogel, Ulrich
in
Adhesins, Bacterial
,
Adhesins, Bacterial - analysis
,
Antigens, Bacterial
2013
A novel multicomponent vaccine against meningococcal capsular group B (MenB) disease contains four major components: factor-H-binding protein, neisserial heparin binding antigen, neisserial adhesin A, and outer-membrane vesicles derived from the strain NZ98/254. Because the public health effect of the vaccine, 4CMenB (Novartis Vaccines and Diagnostics, Siena, Italy), is unclear, we assessed the predicted strain coverage in Europe.
We assessed invasive MenB strains isolated mainly in the most recent full epidemiological year in England and Wales, France, Germany, Italy, and Norway. Meningococcal antigen typing system (MATS) results were linked to multilocus sequence typing and antigen sequence data. To investigate whether generalisation of coverage applied to the rest of Europe, we also assessed isolates from the Czech Republic and Spain.
1052 strains collected from July, 2007, to June, 2008, were assessed from England and Wales, France, Germany, Italy, and Norway. All MenB strains contained at least one gene encoding a major antigen in the vaccine. MATS predicted that 78% of all MenB strains would be killed by postvaccination sera (95% CI 63–90, range of point estimates 73–87% in individual country panels). Half of all strains and 64% of covered strains could be targeted by bactericidal antibodies against more than one vaccine antigen. Results for the 108 isolates from the Czech Republic and 300 from Spain were consistent with those for the other countries.
MATS analysis showed that a multicomponent vaccine could protect against a substantial proportion of invasive MenB strains isolated in Europe. Monitoring of antigen expression, however, will be needed in the future.
Novartis Vaccines and Diagnostics.
Journal Article
Asymptomatic carriage of Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae, Group A Streptococcus and Staphylococcus aureus among adults aged 65 years and older
2019
The aim of this study was to determine the prevalence of Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae, group A Streptococcus (GAS), and Staphylococcus aureus in asymptomatic elderly people and to unravel risk factors leading to colonization.
A multi-centre cross-sectional study was conducted including 677 asymptomatic adults aged 65 years or more, living at home or in nursing homes. Study areas were Greater Aachen (North-Rhine-Westphalia) and Wuerzburg (Bavaria), both regions with medium to high population density. Nasal and oropharyngeal swabs as well as questionnaires were collected from October 2012 to May 2013. Statistical analysis included multiple logistic regression models.
The carriage rate was 1.9% ([95%CI: 1.0-3.3%]; 13/677) for H. influenzae, 0.3% ([95%CI: 0-1.1%]; 2/677) for N. meningitidis and 0% ([95% CI: 0-0.5%]; 0/677) for S. pneumoniae and GAS. Staphylococcus aureus was harboured by 28.5% of the individuals ([95% CI: 25.1-32.1%]; 193/677) and 0.7% ([95% CI: 0.2-1.7%]; 5/677) were positive for methicillin-resistant S. aureus. Among elderly community-dwellers colonization with S. aureus was significantly associated with higher educational level (adjusted OR: 1.905 [95% CI: 1.248-2.908]; p = 0.003). Among nursing home residents colonization was associated with being married (adjusted OR: 3.367 [1.502-7.546]; p = 0.003).
The prevalence of N. meningitidis, H. influenzae, S. pneumoniae and GAS was low among older people in Germany. The S. aureus rate was expectedly high, while MRSA was found in less than 1% of the individuals.
Journal Article
Comprehensive integrated NGS-based surveillance and contact-network modeling unravels transmission dynamics of vancomycin-resistant enterococci in a high-risk population within a tertiary care hospital
by
Fuchs, Stephan
,
Bender, Jennifer K.
,
Brockmann, Dirk
in
Antibiotic resistance
,
Antibiotics
,
Bioinformatics
2020
Vancomycin-resistant E. faecium (VRE) are an important cause of nosocomial infections, which are rapidly transmitted in hospitals. To identify possible transmission routes, we applied combined genomics and contact-network modeling to retrospectively evaluate routine VRE screening data generated by the infection control program of a hemato-oncology unit. Over 1 year, a total of 111 VRE isolates from 111 patients were collected by anal swabs in a tertiary care hospital in Southern Germany. All isolated VRE were whole-genome sequenced, followed by different in-depth bioinformatics analyses including genotyping and determination of phylogenetic relations, aiming to evaluate a standardized workflow. Patient movement data were used to overlay sequencing data to infer transmission events and strain dynamics over time. A predominant clone harboring vanB and exhibiting genotype ST117/CT469 (n = 67) was identified. Our comprehensive combined analyses suggested intra-hospital spread, especially of clone ST117/CT469, despite of extensive screening, single room placement, and contact isolation. A new interactive tool to visualize these complex data was designed. Furthermore, a patient-contact network-modeling approach was developed, which indicates both the periodic import of the clone into the hospital and its spread within the hospital due to patient movements. The analyzed spread of VRE was most likely due to placement of patients in the same room prior to positivity of screening. We successfully demonstrated the added value for this combined strategy to extract well-founded knowledge from interdisciplinary data sources. The combination of patient-contact modeling and high-resolution typing unraveled the transmission dynamics within the hospital department and, additionally, a constant VRE influx over time.
Journal Article
Lymphocytic Myocarditis in Children with Parvovirus B19 Infection: Pathological and Molecular Insights
2024
Background: This study aims to evaluate the role of parvovirus B19 (B19V) in the pathogenesis of myocarditis in a paediatric population, including post-mortem samples from two children. Methods: From 2004 to 2023, endomyocardial biopsies (EMBs) from children under 16 years of age were analyzed using histology, immunohistochemistry, and molecular pathology. A total of 306 children with acute and 1060 children with chronic lymphocytic myocarditis were identified. Results: B19V infection was more frequent in acute myocarditis than in chronic myocarditis (43% vs. 14%), with higher viral loads in acute cases regardless of age. The most prominent cardiac CD3+ T cell infiltration was noted in children < 2 years, correlating with high cardiac B19V loads. In two male infants who died from B19V infection, B19V DNA was localized in the endothelial cells of multiple organs using in situ hybridization. Virus replication was found in the endothelial cells of small cardiac arterioles and venules but not in capillaries. B19V DNA/mRNA was also detected in immune cells, especially in the spleen and lymph nodes, revealing virus replication in B lymphocytes. Conclusions: B19V can induce severe lymphocytic myocarditis, especially in young children. The simultaneous histopathological and molecular assessment of EMBs is important for early diagnosis of viral myocarditis, preventing severe disease, and ensuring appropriate therapy.
Journal Article
Evolutionary Events Associated with an Outbreak of Meningococcal Disease in Men Who Have Sex with Men
by
Prior, Karola
,
Vogel, Ulrich
,
Parent du Châtelet, Isabelle
in
Analysis
,
Animals
,
Bacterial infections
2016
Meningococci spread via respiratory droplets, whereas the closely related gonococci are transmitted sexually. Several outbreaks of invasive meningococcal disease have been reported in Europe and the United States among men who have sex with men (MSM). We recently identified an outbreak of serogroup C meningococcal disease among MSM in Germany and France. In this study, genomic and proteomic techniques were used to analyze the outbreak isolates. In addition, genetically identical urethritis isolates were recovered from France and Germany and included in the analysis. Genome sequencing revealed that the isolates from the outbreak among MSM and from urethritis cases belonged to a clade within clonal complex 11. Proteome analysis showed they expressed nitrite reductase, enabling anaerobic growth as previously described for gonococci. Invasive isolates from MSM, but not urethritis isolates, further expressed functional human factor H binding protein associated with enhanced survival in a newly developed transgenic mouse model expressing human factor H, a complement regulatory protein. In conclusion, our data suggest that urethritis and outbreak isolates followed a joint adaptation route including adaption to the urogenital tract.
Journal Article
Comparative Genome Sequencing Reveals Within-Host Genetic Changes in Neisseria meningitidis during Invasive Disease
by
Blom, Jochen
,
Frosch, Matthias
,
Müller, Tobias
in
Bacteria
,
Bacterial infections
,
Bioinformatics
2017
Some members of the physiological human microbiome occasionally cause life-threatening disease even in immunocompetent individuals. A prime example of such a commensal pathogen is Neisseria meningitidis, which normally resides in the human nasopharynx but is also a leading cause of sepsis and epidemic meningitis. Using N. meningitidis as model organism, we tested the hypothesis that virulence of commensal pathogens is a consequence of within host evolution and selection of invasive variants due to mutations at contingency genes, a mechanism called phase variation. In line with the hypothesis that phase variation evolved as an adaptation to colonize diverse hosts, computational comparisons of all 27 to date completely sequenced and annotated meningococcal genomes retrieved from public databases showed that contingency genes are indeed enriched for genes involved in host interactions. To assess within-host genetic changes in meningococci, we further used ultra-deep whole-genome sequencing of throat-blood strain pairs isolated from four patients suffering from invasive meningococcal disease. We detected up to three mutations per strain pair, affecting predominantly contingency genes involved in type IV pilus biogenesis. However, there was not a single (set) of mutation(s) that could invariably be found in all four pairs of strains. Phenotypic assays further showed that these genetic changes were generally not associated with increased serum resistance, higher fitness in human blood ex vivo or differences in the interaction with human epithelial and endothelial cells in vitro. In conclusion, we hypothesize that virulence of meningococci results from accidental emergence of invasive variants during carriage and without within host evolution of invasive phenotypes during disease progression in vivo.
Journal Article
Structural and mechanistic basis of capsule O-acetylation in Neisseria meningitidis serogroup A
2020
O
-Acetylation of the capsular polysaccharide (CPS) of
Neisseria meningitidis
serogroup A (NmA) is critical for the induction of functional immune responses, making this modification mandatory for CPS-based anti-NmA vaccines. Using comprehensive NMR studies, we demonstrate that
O
-acetylation stabilizes the labile anomeric phosphodiester-linkages of the NmA-CPS and occurs in position C3 and C4 of the
N
-acetylmannosamine units due to enzymatic transfer and non-enzymatic ester migration, respectively. To shed light on the enzymatic transfer mechanism, we solved the crystal structure of the capsule
O
-acetyltransferase CsaC in its apo and acceptor-bound form and of the CsaC-H228A mutant as trapped acetyl-enzyme adduct in complex with CoA. Together with the results of a comprehensive mutagenesis study, the reported structures explain the strict regioselectivity of CsaC and provide insight into the catalytic mechanism, which relies on an unexpected Gln-extension of a classical Ser-His-Asp triad, embedded in an α/β-hydrolase fold.
Neisseria meningitidis
capsular polysaccharide (CPS) is a major virulence factor and vaccine formulations against Neisseria meningitidis serogroup A (NmA) contain
O
-acetylated CPS. Here, the authors provide mechanistic insights into CPS
O
-acetylation in NmA by determining the crystal structure of the
O
-acetyltransferase CsaC and NMR measurements further reveal that the CsaC-mediated reaction is regioselective for O3 and that the O4 modification results from spontaneous
O
-acetyl migration.
Journal Article