Johannes Elias
Research interests
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InterestsMolecular Epidemiology of Bacterial Infectious Agents
Other
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LanguagesGerman, Spanish, Hungarian, English
Publications
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0.45Impact points
[Infections with Pneumococci, Menigococci, H. influenzae and Diphtheria in Germany: the RKI Reference Network for Invasive Bacterial Infections (IBI) at the 5th Würzburg Workshop on Epidemiology, Prevention and Therapy for Invasive Meningococcal Diseases 2010 (Meeting Report).]
Gesundheitswesen (Bundesverband der Arzte des Offentlichen Gesundheitsdienstes (Germany)). 12/2011;
The surveillance and prevention of invasive bacterial infections requires flexible strategic coordination of all involved health-care professionals. For this purpose, the German National Reference Centres for Meningococci, Streptococci and the Consultant Laboratories for Haemophilus influenzae and d... [more] The surveillance and prevention of invasive bacterial infections requires flexible strategic coordination of all involved health-care professionals. For this purpose, the German National Reference Centres for Meningococci, Streptococci and the Consultant Laboratories for Haemophilus influenzae and diphtheria have formed the Reference Network for Invasive bacterial infections (IBI). The 5th Würzburg Workshop on Meningococcal Diseases 2010 provided the network with a forum for the interdisciplinary exchange between scientists, public health professionals, medical microbiologists and clinicians. The topics covered the analysis of surveillance data for meningococcal disease in the last decade, as well as methods to control for antibody response following vaccination, including a serum bactericidal antibody (SBA) assay, and the development of new vaccines that also include the most common serogroup B. The presentation on diphtheria showed that this rare disease in Germany has become a diagnostic challenge, and that apart from the classical pathogen also toxigenic C. ulcerans strains must be considered. Due to the successful vaccination against Hib, H. influenzae disease has changed from a classical childhood disease to an infection of elderly people mainly caused by unencapsulated strains. Following the introduction of vaccines, changes in the serotype distribution and antibiotic resistance profiles have become apparent for S. pneumoniae infections. The epidemiological data were complemented by clinical aspects concerning the vaccination of immunocompromised children.
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1.57Impact points
Immunogenicity of meningococcus C vaccination in a patient with atypical hemolytic uremic syndrome (aHUS) on eculizumab therapy.
Pediatric transplantation. 10/2011;
Zlamy M, Hofer J, Elias J, Vogel U, Frosch M, Jungraithmayr T, Zimmerhackl LB, Prelog M. Immunogenicity of meningococcus C vaccination in a patient with atypical hemolytic uremic syndrome (aHUS) on eculizumab therapy. Pediatr Transplantation 2011. © 2011 John Wiley & Sons A/S. Abstract: We repo... [more] Zlamy M, Hofer J, Elias J, Vogel U, Frosch M, Jungraithmayr T, Zimmerhackl LB, Prelog M. Immunogenicity of meningococcus C vaccination in a patient with atypical hemolytic uremic syndrome (aHUS) on eculizumab therapy. Pediatr Transplantation 2011. © 2011 John Wiley & Sons A/S. Abstract: We report successful kidney transplantation in a 10-yr-old boy with aHUS and heterozygous factor H mutation using the terminal complement inhibitor eculizumab to avoid recurrence of aHUS in the renal graft. Vaccination against meningococcus C (Men C) is essential in patients with dysfunction of the complement system, as induced by eculizumab. In our patient, we report waning SBA titers but maintenance of protective SBA titers (≥1:8) after kidney transplantation under immunosuppressive therapy with mycophenolate mofetil, tacrolimus, steroids, and eculizumab over a 27-month observational period. Our case illustrates that a humoral immune response to conjugate Men C vaccination may be mounted and maintained despite chronic renal disease, kidney transplantation, immunosuppressive drugs, and immunomodulatory therapy with eculizumab. However, it remains unclear whether serologically defined protective SBA titers mediate true protection from invasive meningococcal disease in an immunocompromised patient, particularly under treatment with a complement inhibitor. Thus, close monitoring of SBA titers seems mandatory in this patient.
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3.62Impact points
Immunogenicity of conjugate meningococcus C vaccine in pediatric solid organ transplant recipients.
Vaccine. 06/2011; 29(37):6163-6.
The present study was aimed to evaluate the immunogenicity of a single dose of conjugate Meningococcus C (Men C) vaccine by analyzing the serum bactericidal antibody (SBA) titers in 10 pediatric solid organ transplant (SOT) patients. Four patients showed a delayed immune response after 1 month, but ... [more] The present study was aimed to evaluate the immunogenicity of a single dose of conjugate Meningococcus C (Men C) vaccine by analyzing the serum bactericidal antibody (SBA) titers in 10 pediatric solid organ transplant (SOT) patients. Four patients showed a delayed immune response after 1 month, but all patients demonstrated an increase of SBA titers after vaccination. A significant decrease of SBA titers was seen after 6 months. However, all patients maintained protective SBA titers (≥1:8) despite rapidly waning titers. For patients with significantly decreasing titers, a booster dose may be discussed with close monitoring of SBA titers over time.
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2.80Impact points
New diagnostic PCR for Haemophilus influenzae serotype e based on the cap locus of strain ATCC 8142.
International journal of medical microbiology : IJMM. 10/2010; 301(2):176-9.
A new PCR protocol for molecular typing of Haemophilus influenzae serotype e (Hie) was developed. To this end, the sequence of the cap region II of Hie strain ATCC8142 was identified, which was >99% identical to the recently published sequence of Hie isolate 274. The PCR using primer pair TTL63/T... [more] A new PCR protocol for molecular typing of Haemophilus influenzae serotype e (Hie) was developed. To this end, the sequence of the cap region II of Hie strain ATCC8142 was identified, which was >99% identical to the recently published sequence of Hie isolate 274. The PCR using primer pair TTL63/TTL64 amplifies an internal 592-bp fragment of ecs4, an e-specific capsule synthesis gene, in 40 of 40 Hie strains. Of all non-Hie strains, there were no false positives. False-negative results of the PCR proposed by Falla et al. (1994) are explained by single nucleotide insertions in the primer sequences.
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4.01Impact points
Nosocomial outbreak of VIM-2 metallo-β-lactamase-producing Pseudomonas aeruginosa associated with retrograde urography.
Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases. 09/2010; 16(9):1494-500.
Pseudomonas aeruginosa is well adapted to the hospital setting and can cause a wide array of nosocomial infections that occasionally culminate in recalcitrant outbreaks. In the present study, we describe the first nosocomial outbreak of infection caused by bla(VIM-2)-positive P. aeruginosa in German... [more] Pseudomonas aeruginosa is well adapted to the hospital setting and can cause a wide array of nosocomial infections that occasionally culminate in recalcitrant outbreaks. In the present study, we describe the first nosocomial outbreak of infection caused by bla(VIM-2)-positive P. aeruginosa in Germany. In November and December 2007, highly resistant P. aeruginosa isolates were recovered from the urine of 11 patients in the Department of Urology of a University Hospital. Bacterial isolates were typed by multilocus sequence typing and screened for known metallo-β-lactamase (MBL) genes by PCR. Environmental sources of transmission were tested for bacterial contamination using surveillance cultures. Furthermore, a matched case-control study was performed in search of medical procedures significantly associated with case status. Typing of recovered isolates confirmed VIM-2 MBL-producing P. aeruginosa of sequence type 175 in all cases. Surveillance cultures did not lead to the identification of an environmental source of the outbreak strain. Case-control analysis revealed retrograde urography as the only exposure significantly associated with case status. The analyses suggest the transmission of a single clone of VIM-2 MBL-producing P. aeruginosa leading to the infection of 11 patients within 47 days. Events in temporal proximity to retrograde urographies appear to have facilitated infection in the majority of cases. Department-specific infection control measures, including reinforced hygiene procedures during retrograde urography, quickly terminated the outbreak.
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4.80Impact points
First survey of metallo-beta-lactamases in clinical isolates of Pseudomonas aeruginosa in a German university hospital.
Antimicrobial agents and chemotherapy. 05/2010; 54(8):3493-7.
A total of 489 clinical isolates of Pseudomonas aeruginosa was investigated for metallo-beta-lactamase (MBL) production. Molecular analysis detected a blaVIM-1 gene in the chromosome of one isolate and a blaVIM-2 gene carried on the plasmid in seven isolates. Moreover, we showed that an initial scre... [more] A total of 489 clinical isolates of Pseudomonas aeruginosa was investigated for metallo-beta-lactamase (MBL) production. Molecular analysis detected a blaVIM-1 gene in the chromosome of one isolate and a blaVIM-2 gene carried on the plasmid in seven isolates. Moreover, we showed that an initial screening by combined susceptibility testing of imipenem and ceftazidime followed by a confirmatory EDTA combination disk test represents a valid alternative to the molecular investigation of MBL genes, making MBL detection possible in routine diagnostic laboratories.
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Comparison of two interferon-γ release assays and tuberculin skin test for detecting latent tuberculosis in patients with immune-mediated inflammatory diseases
Annals of the Rheumatic Diseases. 04/2010; 69::782 -784.
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6.79Impact points
Vaccine preventability of meningococcal clone, Greater Aachen Region, Germany.
Emerging infectious diseases. 03/2010; 16(3):465-72.
Emergence of serogroup B meningococci of clonal complex sequence type (ST) 41/44 can cause high levels of disease, as exemplified by a recent epidemic in New Zealand. Multiplication of annual incidence rates (3.1 cases/100,000 population) of meningococcal disease in a defined German region, the city... [more] Emergence of serogroup B meningococci of clonal complex sequence type (ST) 41/44 can cause high levels of disease, as exemplified by a recent epidemic in New Zealand. Multiplication of annual incidence rates (3.1 cases/100,000 population) of meningococcal disease in a defined German region, the city of Aachen and 3 neighboring countries (Greater Aachen) prompted us to investigate and determine the source and nature of this outbreak. Using molecular typing and geographic mapping, we analyzed 1,143 strains belonging to ST41/44 complex, isolated from persons with invasive meningococcal disease over 6 years (2001-2006) from 2 German federal states (total population 26 million) and the Netherlands. A spatially slowly moving clone with multiple-locus variable-number tandem repeat analysis type 19, ST42, and antigenic profile B:P1.7-2,4:F1-5 was responsible for the outbreak. Bactericidal activity in serum samples from the New Zealand MeNZB vaccination campaign confirmed vaccine preventability. Because this globally distributed epidemic strain spreads slowly, vaccination efforts could possibly eliminate meningococcal disease in this area.
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5.36Impact points
A dual role of extracellular DNA during biofilm formation of Neisseria meningitidis.
Molecular microbiology. 02/2010; 75(6):1355-71.
Major pathogenic clonal complexes (cc) of Neisseria meningitidis differ substantially in their point prevalence among healthy carriers. We show that frequently carried pathogenic cc (e.g. sequence type ST-41/44 cc and ST-32 cc) depend on extracellular DNA (eDNA) to initiate in vitro biofilm formatio... [more] Major pathogenic clonal complexes (cc) of Neisseria meningitidis differ substantially in their point prevalence among healthy carriers. We show that frequently carried pathogenic cc (e.g. sequence type ST-41/44 cc and ST-32 cc) depend on extracellular DNA (eDNA) to initiate in vitro biofilm formation, whereas biofilm formation of cc with low point prevalence (ST-8 cc and ST-11 cc) was eDNA-independent. For initial biofilm formation, a ST-32 cc type strain, but not a ST-11 type strain, utilized eDNA. The release of eDNA was mediated by lytic transglycosylase and cytoplasmic N-acetylmuramyl-L-alanine amidase genes. In late biofilms, outer membrane phospholipase A-dependent autolysis, which was observed in most cc, but not in ST-8 and ST-11 strains, was required for shear force resistance of microcolonies. Taken together, N. meningitidis evolved two different biofilm formation strategies, an eDNA-dependent one yielding shear force resistant microcolonies, and an eDNA-independent one. Based on the experimental findings and previous epidemiological observations, we hypothesize that most meningococcal cc display a settler phenotype, which is eDNA-dependent and results in a stable interaction with the host. On the contrary, spreaders (ST-11 and ST-8 cc) are unable to use eDNA for biofilm formation and might compensate for poor colonization properties by high transmission rates.
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8.11Impact points
Comparison of two interferon-gamma release assays and tuberculin skin test for detecting latent tuberculosis in patients with immune-mediated inflammatory diseases.
Annals of the rheumatic diseases. 02/2010; 69(4):782-4.
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5.50Impact points
O-acetyltransferase gene neuO is segregated according to phylogenetic background and contributes to environmental desiccation resistance in Escherichia coli K1.
Environmental microbiology. 09/2009;
Escherichia coli K1 causes disease in humans and birds. Its polysialic acid capsule can be O-acetylated via phase-variable expression of the acetyltransferase NeuO encoded by prophage CUS-3. The role of capsule O-acetylation in ecological adaptation or pathogenic invasion of E. coli K1 is largely un... [more] Escherichia coli K1 causes disease in humans and birds. Its polysialic acid capsule can be O-acetylated via phase-variable expression of the acetyltransferase NeuO encoded by prophage CUS-3. The role of capsule O-acetylation in ecological adaptation or pathogenic invasion of E. coli K1 is largely unclear. A population genetics approach was performed to study the distribution of neuO among E. coli K1 isolates from human and avian sources. Multilocus sequence typing revealed 39 different sequence types (STs) among 183 E. coli K1 strains. The proportion of the ST95 complex (STC95) was 44%. NeuO was found in 98% of the STC95 strains, but only in 24% of other STs. Grouping of STs and prophage genotypes revealed a segregation of prophage types according to STs, suggesting coevolution of CUS-3 and the E. coli K1 host. Within the STC95, which is known to harbour both human and avian pathogenic isolates, CUS-3 genotypes were shared irrespective of the host species. Functional analysis of a variety of strain pairs revealed that NeuO-mediated K1 capsule O-acetylation enhanced desiccation resistance. In contrast, NeuO expression led to a reduced biofilm formation in biofilm positive E. coli K1 isolates. These findings suggest a delicate ecological balance of neuO'on'/'off' switching.
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4.16Impact points
Life-threatening infection caused by daptomycin-resistant Corynebacterium jeikeium in a neutropenic patient.
Journal of clinical microbiology. 06/2009;
Daptomycin is a novel lipopeptide antibiotic agent approved for the treatment of gram-positive life-threatening infections. Here we report, for the first time, the isolation of a highly daptomycin-resistant strain of Corynebacterium jeikeium causing a life-threatening infection in a neutropenic pati... [more] Daptomycin is a novel lipopeptide antibiotic agent approved for the treatment of gram-positive life-threatening infections. Here we report, for the first time, the isolation of a highly daptomycin-resistant strain of Corynebacterium jeikeium causing a life-threatening infection in a neutropenic patient undergoing cord blood transplantation for secondary acute myeloid leukemia.
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Laboratory diagnostics of Neisseria meningitidis from the viewpoint of the German Reference Laboratory for Meningococci
LaboratoriumsMedizin. 01/2009; 33(5):245-253.
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2.45Impact points
EpiScanGIS: an online geographic surveillance system for meningococcal disease.
International journal of health geographics. 08/2008; 7(1):33.
ABSTRACT: BACKGROUND: Surveillance of infectious diseases increasingly relies on Geographic Information Systems (GIS). The integration of pathogen fine typing data in dynamic systems and visualization of spatio-temporal clusters are a technical challenge for system development. RESULTS: An online ge... [more] ABSTRACT: BACKGROUND: Surveillance of infectious diseases increasingly relies on Geographic Information Systems (GIS). The integration of pathogen fine typing data in dynamic systems and visualization of spatio-temporal clusters are a technical challenge for system development. RESULTS: An online geographic information system (EpiScanGIS) based on open source components has been launched in Germany in May 2006 for real time provision of meningococcal typing data in conjunction with demographic information (age, incidence, population density). Spatio-temporal clusters of disease detected by computer assisted cluster analysis (SaTScanTM) are visualized on maps. EpiScanGIS enables dynamic generation of animated maps. The system is based on open source components; its architecture is open for other infectious agents and geographic regions. EpiScanGIS is available at www.episcangis.org, and currently has 80 registered users, mostly from the public health service in Germany. At present more than 2,900 cases of invasive meningococcal disease are stored in the database (data as of June 3, 2008). CONCLUSIONS: EpiScanGIS exemplifies GIS applications and early-warning systems in laboratory surveillance of infectious diseases.
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4.16Impact points
Deletion of the meningococcal fetA gene used for antigen sequence typing of invasive and commensal isolates from Germany: frequencies and mechanisms.
Journal of clinical microbiology. 10/2007; 45(9):2960-4.
Antigen sequence typing (ST) of FetA is part of the molecular typing scheme of Neisseria meningitidis. Among invasive meningococcal isolates from 2,201 patients in Germany, we identified 11 strains lacking the fetA gene because of deletions mediated by repeat arrays flanking the gene, i.e., Correia ... [more] Antigen sequence typing (ST) of FetA is part of the molecular typing scheme of Neisseria meningitidis. Among invasive meningococcal isolates from 2,201 patients in Germany, we identified 11 strains lacking the fetA gene because of deletions mediated by repeat arrays flanking the gene, i.e., Correia elements, repeat sequence 13 (RS13), and duplicated RS3. Geographic mapping and multilocus ST of invasive isolates revealed that fetA deletion was a sporadic event without genetic fixation. Among 821 carrier strains, 12 strains lacked fetA, suggesting that fetA is maintained during asymptomatic carriage. Interestingly, most of these isolates belonged to the multilocus ST-35 clonal complex (cc). ST-35 cc strains and the recently published ST-192 strains from Burkina Faso may benefit from loss of fetA, but their infrequent occurrence among invasive isolates currently does not affect fetA antigen ST.
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2.37Impact points
Capture-recapture analysis to estimate the incidence of invasive meningococcal disease in Germany, 2003.
Epidemiology and infection. 06/2007; 135(4):657-64.
The incidence of invasive meningococcal disease (IMD) in Germany in 2003 was estimated by the two-source capture-recapture method. As a unique personal identifier was unavailable, cases with IMD tested at the National Reference Centre for Meningococci (NRZM) were matched with cases reported to the R... [more] The incidence of invasive meningococcal disease (IMD) in Germany in 2003 was estimated by the two-source capture-recapture method. As a unique personal identifier was unavailable, cases with IMD tested at the National Reference Centre for Meningococci (NRZM) were matched with cases reported to the Robert Koch Institute (RKI) through the statutory surveillance system by using demographic and disease-specific variables common to both datasets. The estimated overall incidence was 1.1 IMD cases/100,000 inhabitants, with a sensitivity of ascertainment of 64.8% for NRZM and 89.4% for RKI. Case-fatality rate was estimated at 8.8%. Adjustment for heterogeneity of capture according to age, region and serogroup observed in the NRZM (but not RKI) source had minimal effect on the estimated incidence. The IMD incidence estimated by capture-recapture analysis is thus only slightly higher than through statutory surveillance data. As a degree of positive dependence between the systems cannot be ruled out, this estimate may still be an underestimate. However, under ascertainment appears insufficient to explain the low incidence of IMD in Germany compared to other European countries.
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0.45Impact points
[3rd Workshop on Epidemiology, Prevention and Treatment of Invasive Meningococcal Disease in Würzburg 2006]
Gesundheitswesen (Bundesverband der Ärzte des Öffentlichen Gesundheitsdienstes (Germany)). 05/2007; 69(4):256-62.
On October 5th, 2006, the German Reference Centre for Meningococci (NRZM) held the 3rd Workshop on Epidemiology, Prevention and Treatment of Invasive Meningococcal Disease, in collaboration with the German Society for Hygiene and Microbiology (DGHM). Given the recent recommendation of the German Sta... [more] On October 5th, 2006, the German Reference Centre for Meningococci (NRZM) held the 3rd Workshop on Epidemiology, Prevention and Treatment of Invasive Meningococcal Disease, in collaboration with the German Society for Hygiene and Microbiology (DGHM). Given the recent recommendation of the German Standing Committee on Vaccination (STIKO) for conjugate meningococcal C vaccination of all children in the second year of life, observations from meningococcal C conjugate vaccination campaigns in other European countries were presented and compared to the German situation. Moreover, the newly implemented cluster detection routines employed at the NRZM and their integration into the interactive geographical information system EpiScanGIS were shown. Based on recent experiences from regional outbreaks in Oberallgäu, Sangerhausen, and Greater Aachen, examples for public health intervention were given at the conference. In addition, current developments in the area of meningococcal research, as well as trends in antimicrobial susceptibility were covered. Finally, the latest evidence concerning the clinical management and chemoprophylaxis of this invasive bacterial disease was discussed.
Following (4)
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Michael Höhle
Robert Koch Institut -
Alexander Mellmann
Westfälische Wilhelms-Universität Münster -
Oliver Kurzai
Friedrich-Schiller-Universität Jena
