22 results on '"Litzba, Nadine"'
Search Results
2. A novel rhabdovirus, related to Merida virus, in field-collected mosquitoes from Anatolia and Thrace
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Ergünay, Koray, Brinkmann, Annika, Litzba, Nadine, Günay, Filiz, Kar, Sırrı, Öter, Kerem, Örsten, Serra, Sarıkaya, Yasemen, Alten, Bülent, Nitsche, Andreas, and Linton, Yvonne-Marie
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- 2017
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3. Implementierung der Internationalen Gesundheitsvorschriften in Deutschland 2019 – Joint External Evaluation (JEE) der Weltgesundheitsorganisation (WHO)
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Grote, Ulrike, additional, an der Heiden, Maria, additional, Litzba, Nadine, additional, Jeglitza, Matthias, additional, Lücking, Gesa, additional, Bayer, Christophe, additional, and Rexroth, Ute, additional
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- 2022
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4. Surveillance während einer Pandemie: SARS-CoV-2 Fall- und Kontaktpersonennachverfolgung mit grenzüberschreitendem Bezug in Deutschland, 2020
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Sperle, Ida, additional, Lachmann, Raskit, additional, Koppe, Uwe, additional, Litzba, Nadine, additional, Vonderwolke, Robert, additional, Püschel, Nadine, additional, Baum, Jonathan, additional, Ghebreghiorghis, Luam, additional, Steffen, Gyde, additional, Rexroth, Ute, additional, an der Heiden, Maria, additional, Schneider, Timm, additional, and Markus, Inessa, additional
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- 2022
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5. Immunogenicity and safety of yellow fever vaccination for 102 HIV-infected patients
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Veit, Olivia, Niedrig, Matthias, Chapuis-Taillard, Caroline, Cavassini, Matthias, Mossdorf, Erik, Schmid, Patrick, Bae, Hi-Gung, Litzba, Nadine, Staub, Thomas, Hatz, Christoph, and Furrer, Hansjakob
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Immunization -- Safety and security measures ,Yellow fever -- Prevention ,Yellow fever -- Research ,Human immunogenetics -- Research ,HIV infection -- Care and treatment ,HIV infection -- Physiological aspects ,HIV infection -- Research ,Health ,Health care industry - Published
- 2009
6. Fachliche Einschätzung zur Durchführung von Temperaturmessungen und anderen Methoden im Rahmen von Entry- und Exit-Screening an Flughäfen während der COVID-19-Lage, Deutschland
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an der Heiden, Maria, Litzba, Nadine, Hoch, Martin, Schumann, Astrid, Dirksen-Fischer, Martin, Boldt, Matthias, Kalkowski, Mathias, Kleine-Kampmann, Scarlett, Ehlers, Lena, Götsch, Udo, Trost, Matthias, Göbels, Klaus, Kolenbrander, Anne, Jeglitza, Matthias, Seidel, Juliane, and Rexroth, Ute
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Entry-Screening ,Grenzübergang ,COVID-19 ,ddc:610 ,Flugverkehr ,610 Medizin und Gesundheit ,Internationale Gesundheitsvorschriften - Abstract
Bei früheren Ausbrüchen wie SARS (2003) und der pandemischen Influenza A (H1N1) (2009) hat sich der Einsatz von Screening-Verfahren nicht als wirksam erwiesen, um Fälle zu erkennen. Entry- und Exit-Screening-Maßnahmen in Deutschland würden erhebliche personelle Ressourcen an Grenzübergangsstellen erfordern, die der ÖGD in anderen Bereichen sinnvoller einsetzen könnte. Wie im Epidemiologischen Bulletin 20/2020 ausgeführt wird, werden insgesamt Entry- und Exit-Screening-Maßnahmen an Flughäfen mit Temperaturmessungen bei der COVID-19-Bewältigung in Deutschland für ineffektiv und der mögliche Mehrwert als vernachlässigbar eingeschätzt.
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- 2020
7. Letter to the editor: Pending challenges in passenger contact tracing in air transport – a German perspective
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Seidel, Juliane, primary, Matysiak-Klose, Dorothea, additional, Jeglitza, Matthias, additional, and Litzba, , Nadine, additional
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- 2019
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8. Additional file 2: Table S2. of Co-circulation of West Nile virus and distinct insect-specific flaviviruses in Turkey
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Ergünay, Koray, Litzba, Nadine, Brinkmann, Annika, Günay, Filiz, Sarıkaya, Yasemen, Sırrı Kar, Örsten, Serra, Öter, Kerem, Domingo, Cristina, Kasap, Özge Erisoz, Özkul, Aykut, Mitchell, Luke, Nitsche, Andreas, Alten, Bülent, and Yvonne-Marie Linton
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body regions ,nervous system ,viruses ,fungi ,biochemical phenomena, metabolism, and nutrition - Abstract
Comparison of the amino acid substitutions observed in the viral polyprotein (PDF 81 kb)
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- 2017
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9. Additional file 1: Table S1. of Co-circulation of West Nile virus and distinct insect-specific flaviviruses in Turkey
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Ergünay, Koray, Litzba, Nadine, Brinkmann, Annika, Günay, Filiz, Sarıkaya, Yasemen, Sırrı Kar, Örsten, Serra, Öter, Kerem, Domingo, Cristina, Kasap, Özge Erisoz, Özkul, Aykut, Mitchell, Luke, Nitsche, Andreas, Alten, Bülent, and Yvonne-Marie Linton
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body regions ,nervous system ,viruses ,fungi - Abstract
Pairwise comparison of the nucleotide and putative amino acid (in parentheses) sequences of the ISF polyprotein (PDF 58 kb)
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- 2017
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10. Co-circulation of West Nile virus and distinct insect-specific flaviviruses in Turkey
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Ergünay, Koray, primary, Litzba, Nadine, additional, Brinkmann, Annika, additional, Günay, Filiz, additional, Sarıkaya, Yasemen, additional, Kar, Sırrı, additional, Örsten, Serra, additional, Öter, Kerem, additional, Domingo, Cristina, additional, Erisoz Kasap, Özge, additional, Özkul, Aykut, additional, Mitchell, Luke, additional, Nitsche, Andreas, additional, Alten, Bülent, additional, and Linton, Yvonne-Marie, additional
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- 2017
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11. Isolation and genomic characterization of Culex theileri flaviviruses in field-collected mosquitoes from Turkey
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Ergünay, Koray, primary, Litzba, Nadine, additional, Brinkmann, Annika, additional, Günay, Filiz, additional, Kar, Sırrı, additional, Öter, Kerem, additional, Örsten, Serra, additional, Sarıkaya, Yasemen, additional, Alten, Bülent, additional, Nitsche, Andreas, additional, and Linton, Yvonne-Marie, additional
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- 2016
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12. Etablierung und Evaluierung serologischer Teste zur Detektion hochpathogener Arboviren
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Litzba, Nadine
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500 Naturwissenschaften und Mathematik::570 Biowissenschaften ,Biologie ,alphaviruses ,IIFT ,diagnostics ,serology ,immunofluorescence assay ,immunofluorescence test ,bunyaviruses ,IFA ,flaviviruses - Abstract
Für viele tropische Infektionserreger herrscht ein Mangel an guten, kommerziell hergestellten, serologischen Testen. Meist beruht die serologische Diagnostik für arbovirale Erreger auf in-house Testen und ist nur in wenigen Laboren verfügbar. Eine schnelle Diagnostik ist jedoch unerlässlich, um z.B. eine eingeschleppte, tropische Krankheit erkennen und im Notfall die nötigen Gegenmaßnahmen treffen zu können. Um einer größeren Zahl von Laboratorien qualitätsgesicherte, serologische Nachweissysteme zur Verfügung zu stellen, wurden im Rahmen der Promotionsarbeit umfangreiche Testevaluierungen für die fünf folgenden, mit Virus-Vollantigen hergestellten Immunfluoreszenzteste (IIFTs) durchgeführt und die Ergebnisse ausgewertet: anti-Chikungunya-Virus (CHIKV), anti-Japanisches Encephalitis-Virus (JEV), anti-Dengue-Virus (DENV), anti-Sandfliegen-Fieber-Viren (SFV) und anti-Rifttalfieber-Virus (RVFV) IIFT. Zudem wurden zwei rekombinante Testsysteme, für das Krim-Kongo Hämorrhagisches Fieber-Virus (CCHFV) und das DENV entwickelt und beide Teste ebenfalls in einer Studie mit charakterisierten Serumpanels evaluiert. Der anti-CHIKV IIFT wurde im Vergleich zu zwei in-house Testen evaluiert. Er zeigte für IgM eine Sensitivität von 96,9 %, sowie eine Spezifität von 98,3 %. Für den IgG-IIFT wurde eine Sensitivität von 95,4 % und eine Spezifität von 100 % berechnet. Die Evaluierung des anti-JEV IIFTs wurde im Vergleich zu zwei kommerziellen ELISAs und einem Plaque-Reduktions-Neutralisationstest (PRNT) durchgeführt. Der IgM-IIFT zeigte im Vergleich zum Panbio IgM-ELISA eine Sensitivität von 86 % und eine Spezifität von 95 %. Im Vergleich zum InBios IgM-ELISA wurde für den IgM-IIFT eine Sensitivität von 83,9 % und eine Spezifität von 100 % ermittelt. Der IgG-IIFTs zeigte im Vergleich zum PRNT eine Sensitivität von 93,8 % und eine Spezifität von 100 %. Der anti-DENV IIFT wurde hinsichtlich der Fähigkeit untersucht, den per PCR bestimmten Serotyp der Infektion serologisch zu identifizieren. Mittels des IgM-IIFTs, konnten 52 % der IgM- reaktiven Seren mit dem anti-DENV IIFT richtig serotypisiert werden. Bei weiteren 48 % der Seren zeigten mehrere Serotypen eine gleich starke Fluoreszenz. Bei 92 % dieser Seren war jedoch der per PCR bestimmte, unter den am stärksten reaktiven Serotypen. Der anti-SFV-IIFT wurde mit zwei kommerziell erhältlichen Testen, einem anti-Toscana-Virus (TOSV) ELISA und einem anti-TOSV Blot, verglichen. Die stärkste Reaktivität im ELISA und Blot konnte in den 25 Seren gefunden werden, die im IIFT sowohl mit dem SFV Naples- als auch mit dem TOSV-Substrat reagiert hatten. Während im ELISA 28 % der Seren als positiv detektiert wurden, waren 98 % der Seren im Blot positiv. In den 46 Seren, die im IIFT ausschließlich mit dem TOSV-Substrat reagiert hatten, wurden mit dem ELISA 10,9 % als grenzwertig und mit dem Blot 30 % als positiv identifiziert. Der IIFT zeigte insgesamt eine höhere Sensitivität als der Blot, und eine viel höhere Sensitivität als der ELISA. Der anti-RVFV IIFT wurde im Vergleich zu einem in-house ELISA evaluiert. Die Spezifität des IgM-IIFTs lag bei 99,4 %, die Sensitivität konnte aufgrund der zu geringen Probenanzahl nicht ermittelt werden. Der IgG-IIFT zeigte eine Sensitivität von 93,3 % und eine Spezifität von 99,5 %. Es wurde ein rekombinanter anti-CCHFV IIFT entwickelt. Dafür wurde zunächst die Transfektion und Expression des Nukleoproteins und der Glykoproteine in HEK 293RKI-Zellen optimiert. Der anti-CCHFV IIFT wurde im Anschluss mit vier verschiedenen Serumpanels, die in verschiedenen in-house ELISAs als anti-CCHFV-positiv vorcharakterisiert worden waren, und einem Panel von Blutspenderseren analysiert. Die Ergebnisse dieser Serumpanels, v.a. für den IgM-IIFT, unterschieden sich stark. Die Sensitivitäten für den IgM-IIFT lagen bei 54,3 %, 44,4 %, 93,3 %, sowie 92,9 % und die Spezifität bei 97,8 %. Für den IgG-IIFT lagen die Sensitivitäten bei 83,3 %, 100 %, 100 % und 69,2 % und die Spezifität bei 100 %. Für den rekombinanten anti-DENV Test wurden die vier NS1-Proteine ebenfalls jeweils in HEK 293RKI-Zellen exprimiert. Eine korrekte Serotypisierung war mit dem IgG-IIFT im Panel 1 bei 54,5 % der IgG- reaktiven Seren und im Panel 2, das hauptsächlich aus Seren nach Sekundärinfektion bestand, bei 28,6 % der IgG-reaktiven Seren möglich. Werden im Panel 1 nur die Seren mit den reaktiven DENV-Serotypen 1, 2 und 4 betrachtet, so konnten 75 % im IgG-IIFT richtig serotypisiert werden. Insgesamt zeigten die verschiedenen IIFTs im Vergleich zu den verwendeten in- house bzw. kommerziellen Testen, vergleichbare Ergebnisse und können in den Laboratorien als evaluierte Alternativen zur Diagnose von tropischen, arboviralen Erkrankungen eingesetzt werden. Der IIFT stellt eine schnelle und effiziente Testplattform dar, mit der man vor allem Einzelseren, für die eine Untersuchung im ELISA zu aufwendig ist, analysieren kann. Die Entwicklung rekombinanter IIFTs bietet zudem eine interessante Möglichkeit serologische Teste für Erreger der biologischen Sicherheitsstufe 4 (BSL-4) ohne größere Hindernisse herzustellen, und so auch für höher pathogene Erreger kommerzielle, serologische Diagnostika vielen Laboren zugänglich zu machen. Weiterhin lassen sich durch die Auswahl wenig kreuzreaktiver Proteine bzw. spezifischer Proteinbereiche in rekombinanten Testsystemen störende Kreuzreaktivitäten reduzieren. Insgesamt stellen rekombinant hergestellte Virusantigen-Substrate eine vielversprechende Alternative für die Herstellung von IIFT-BIOCHIPs dar., There is a lack of good and commercially available serological assays for many tropical infectious agents. The serological diagnosis of arboviruses relies mainly on in-house assays and is available only in few laboratories. Yet, a rapid diagnosis is crucial to identify a newly introduced tropical infection and to take the adequate counter measures. In order to provide an increased number of laboratories with quality assured, serological assays, extensive evaluations were performed for the following five indirect immunofluorescence tests (IIFTs) which are all produced with complete virus: anti-Chikungunya virus (CHIKV), anti-Japanese encephalitis virus (JEV), anti-Dengue virus (DENV), anti-Sandfly fever-virus (SFV) und anti-Rift valley fever virus (RVFV) IIFT. Additionally two recombinant test systems for the Crimean Congo hemorrhagic fever virus (CCHFV) and DENV were developed and both assays were likewise evaluated with characterised serum panels. The anti-CHIKV IIFT was evaluated in comparison to two in-house assays. It revealed for IgM a sensitivity of 96.9 % and 98.3 %. For the IgG IIFT the sensitivity was 95.4 % and the specificity 100 %. The evaluation of the anti-JEV IIFT was performed with two commercial ELISAs and a plaque reduction neutralization assay (PRNT). Compared to the Panbio IgM ELISA, the IgM IIFT showed a sensitivity of 86 % and a specificity of 95 %. In comparison to the InBios IgM ELISA the sensitivity was 83.9 % and the specificity 100 %. The IgG IIFT was evaluated against the PRNT and demonstrated a sensitivity of 93.8 % and a specificity of 100 %. The anti-DENV IIFT was analysed in respect to its capability to identify serologically the correct DENV serotype that was determined by PCR beforehand. Using the IgM IIFT, 52 % of the sera containing IgM antibodies were correctly serotyped by the anti-DENV IIFT. In further 48 % of the sera an equal fluorescence was detected, and in 92 % of these sera, the serotype determined by PCR was one of the most reactive serotypes. The anti-SFV IIFT was compared to two commercial assays, an anti-Toscana Virus (TOSV) ELISA and an anti-TOSV blot. The highest reactivity was found in the 25 sera, which reacted in the IIFT with the SFV Naples- and with the TOSV substrate. While 28 % of the sera were detected as positive by ELISA, 98 % were positive on the blot. Of the 46 sera, reactive only with the TOSV IIFT substrate, 10.9 % were equivocal in ELISA and 30 % positive with the blot. Altogether, the IIFT showed a higher sensitivity compared to the blot and a much higher sensitivity than the ELISA. The anti-RVFV IIFT was evaluated in comparison to an in-house ELISA. The specificity of the IgM IIFT was 99.4 %, while it was not possible to determine a sensitivity value, due to an insufficient number of samples. The IgG IIFT showed a sensitivity of 93.3 % and a specificity of 99.5 %. A recombinant anti-CCHFV IIFT was developed. For this, the transfection and expression of the nucleo- and the glycoproteins was optimised in HEK 293RKI cells. Subsequently, the anti-CCHFV IIFT was evaluated with four different sera panels, characterised as anti-CCHFV positive with different in-house ELISAs. The results varied strongly, especially for IgM. The sensitivities for the IgM IIFT were 54.3 %, 44.4 %, 93.3 % and 92.9 %, while the specificity was 97.8 %. For the IgG IIFT the sensitivities were 83.3 %, 100 %, 100 % and 69.2 %, the specificity was 100 %. For the recombinant anti-DENV assay the four NS1 proteins were likewise expressed in HEK 293RKI cells. In Panel 1 it was possible with the IgG IIFT to correctly serotype 54.5 % of the sera reactive with IgG. In Panel 2, which consisted mainly of sera with secondary DENV infections 28.6 % of the IgG-reactive sera were serotyped correctly. Considering only the reactive DENV serotypes 1, 2 and 4, it was possible to serotype 75 % of the sera correctly. Altogether, the different EUROIMMUN IIFTs showed comparable results to in-house and commercial assays and can be used as an extensively evaluated alternative for the diagnosis of tropical, arboviral diseases. The IIFT represents a rapid and efficient platform, especially for the diagnosis of single sera for which the analysis in ELISA is too laborious and cumbersome. The development of recombinant IIFTs provides the opportunity to produce commercial serological assays for biosafety level 4 (BSL-4) agents without need of a high risk containment facility. Thereby, these products for the diagnosis of highly pathogenic viruses become available for many laboratories. Furthermore, it is possible to select less cross reactive proteins or specific regions of proteins for the production of recombinant assays. The reduced cross reactivity allows to distinctively diagnose even highly related viruses. Altogether, recombinantly produced viral antigens represent a promising alternative for the production of IIFT-BIOCHIPs.
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- 2011
13. Evaluation of Different Serological Diagnostic Methods for Tick-Borne Encephalitis Virus : Enzyme-Linked Immunosorbent, Immunofluorescence, and Neutralization Assay
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Litzba, Nadine, Zelena, Hana, Kreil, Thomas R., Niklasson, Bo, Kuehlmann-Rabens, Ilona, Remoli, Maria Elena, Niedrig, Matthias, Litzba, Nadine, Zelena, Hana, Kreil, Thomas R., Niklasson, Bo, Kuehlmann-Rabens, Ilona, Remoli, Maria Elena, and Niedrig, Matthias
- Abstract
Tick-borne encephalitis (TBE) is a zoonotic disease, transmitted mainly by the bite of ticks. The TBE virus (TBEV) belongs to the family Flaviviridae, genus Flavivirus and is able to cause meningoencephalitis. For serological TBEV detection, the neutralization test (NT) is the most specific assay available. Different NT protocols are used in the laboratories, and until now the performance of these NTs has never been tested in an external quality assessment (EQA). In this EQA, we compared the results of eight European laboratories in detecting 17 samples (11 TBEV positive, five flavivirus cross reactive, and one negative sample) by NT. Furthermore, 14 of these EQA samples and 15 additional samples were tested in different commercial assays: 15 immunoglobulin G (IgG) enzyme-linked immunosorbent assays (ELISAs) and an immunofluorescence assay (IFA). Four laboratories showed a good NT EQA performance, whereas four laboratories had some sensitivity problems. Additionally, two of these laboratories showed a lack in specificity, misidentifying a dengue-positive sample as TBEV positive. The comparison of the commercial ELISAs revealed a high sensitivity in all assays, but as expected for IgG, the ELISAs showed a high degree of flavivirus cross reactivity. The assessment of Vienna Units in some of the ELISAs revealed deviations in the standards used by the different companies. Therefore, these standards should be revised. Generally, in this EQA, we found that reliable NT protocols are used in most of the laboratories, and the evaluation of the IgG ELISAs and the IFA showed a good agreement.
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- 2014
- Full Text
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14. Evaluation of Different Serological Diagnostic Methods for Tick-Borne Encephalitis Virus: Enzyme-Linked Immunosorbent, Immunofluorescence, and Neutralization Assay
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Litzba, Nadine, primary, Zelená, Hana, additional, Kreil, Thomas R., additional, Niklasson, Bo, additional, Kühlmann-Rabens, Ilona, additional, Remoli, Maria Elena, additional, and Niedrig, Matthias, additional
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- 2014
- Full Text
- View/download PDF
15. Evaluation of the first commercial chikungunya virus indirect immunofluorescence test
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Litzba, Nadine, Schuffenecker, Isabelle, Zeller, Hervé, Drosten, Christian, Emmerich, Petra, Charrel, Remi, Kreher, Petra, and Niedrig, Matthias
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- 2008
- Full Text
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16. Multicentre evaluation of central nervous system infections due to Flavi and Phleboviruses in Turkey
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Ergunay, Koray, primary, Sayiner, A. Arzu, additional, Litzba, Nadine, additional, Lederer, Sabine, additional, Charrel, Remi, additional, Kreher, Petra, additional, Us, Durdal, additional, Niedrig, Matthias, additional, Ozkul, Aykut, additional, and Hascelik, Gulsen, additional
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- 2012
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17. Medical importance of Sindbis virus in south-west Germany
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Jöst, Hanna, primary, Bürck-Kammerer, Simone, additional, Hütter, Gero, additional, Lattwein, Erik, additional, Lederer, Sabine, additional, Litzba, Nadine, additional, Bock-Hensley, Oswinde, additional, Emmerich, Petra, additional, Günther, Stephan, additional, Becker, Norbert, additional, Niedrig, Matthias, additional, and Schmidt-Chanasit, Jonas, additional
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- 2011
- Full Text
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18. Performance of Various Commercial Assays for the Detection of Toscana Virus Antibodies
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Ergünay, Koray, primary, Litzba, Nadine, additional, Lo, Modou Moustapha, additional, Aydoğan, Sibel, additional, Saygan, Mehmet B., additional, Us, Dürdal, additional, Weidmann, Manfred, additional, and Niedrig, Matthias, additional
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- 2011
- Full Text
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19. Evaluation of Serological Diagnostic Test Systems Assessing the Immune Response to Japanese Encephalitis Vaccination
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Litzba, Nadine, primary, Klade, Christoph S., additional, Lederer, Sabine, additional, and Niedrig, Matthias, additional
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- 2010
- Full Text
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20. Evaluation of different serological diagnostic methods for tick-borne encephalitis virus: enzyme-linked immunosorbent, immunofluorescence, and neutralization assay.
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Litzba N, Zelená H, Kreil TR, Niklasson B, Kühlmann-Rabens I, Remoli ME, and Niedrig M
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- Antibodies, Viral, Cross Reactions, Dengue, Encephalitis, Tick-Borne immunology, Europe, Flavivirus immunology, Humans, Immunoglobulin G, Laboratory Proficiency Testing, Encephalitis Viruses, Tick-Borne immunology, Encephalitis, Tick-Borne diagnosis, Enzyme-Linked Immunosorbent Assay methods, Fluorescent Antibody Technique methods, Neutralization Tests methods
- Abstract
Tick-borne encephalitis (TBE) is a zoonotic disease, transmitted mainly by the bite of ticks. The TBE virus (TBEV) belongs to the family Flaviviridae, genus Flavivirus and is able to cause meningoencephalitis. For serological TBEV detection, the neutralization test (NT) is the most specific assay available. Different NT protocols are used in the laboratories, and until now the performance of these NTs has never been tested in an external quality assessment (EQA). In this EQA, we compared the results of eight European laboratories in detecting 17 samples (11 TBEV positive, five flavivirus cross reactive, and one negative sample) by NT. Furthermore, 14 of these EQA samples and 15 additional samples were tested in different commercial assays: 15 immunoglobulin G (IgG) enzyme-linked immunosorbent assays (ELISAs) and an immunofluorescence assay (IFA). Four laboratories showed a good NT EQA performance, whereas four laboratories had some sensitivity problems. Additionally, two of these laboratories showed a lack in specificity, misidentifying a dengue-positive sample as TBEV positive. The comparison of the commercial ELISAs revealed a high sensitivity in all assays, but as expected for IgG, the ELISAs showed a high degree of flavivirus cross reactivity. The assessment of Vienna Units in some of the ELISAs revealed deviations in the standards used by the different companies. Therefore, these standards should be revised. Generally, in this EQA, we found that reliable NT protocols are used in most of the laboratories, and the evaluation of the IgG ELISAs and the IFA showed a good agreement.
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- 2014
- Full Text
- View/download PDF
21. Performance of various commercial assays for the detection of Toscana virus antibodies.
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Ergünay K, Litzba N, Lo MM, Aydoğan S, Saygan MB, Us D, Weidmann M, and Niedrig M
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- Humans, Immunoglobulin G blood, Immunoglobulin M blood, Reproducibility of Results, Sensitivity and Specificity, Antibodies, Viral blood, Enzyme-Linked Immunosorbent Assay methods, Fluorescent Antibody Technique, Indirect methods, Immunoblotting methods, Neutralization Tests methods, Sandfly fever Naples virus immunology
- Abstract
Introduction: Sandfly fever virus (SFV) serotypes sandfly fever Naples virus, sandfly fever Sicilian virus, and sandfly fever Cyprus virus cause febrile diseases, whereas Toscana virus (TOSV) is responsible for aseptic meningoencephalitis. Diagnosis and surveillance of TOSV depend heavily on virus serology, and various commercial assays utilizing various antigen sources and formats have been available. The aim of this study was to perform comparative evaluation of commercially available serological assays for anti-TOSV immunoglobulins., Materials and Methods: A collection of 120 sera from healthy blood donors from an endemic region, previously identified to be reactive for antibodies against various SFV serotypes by indirect immunofluorescence test (IIFT), was reevaluated for IgG/IgM via IIFT, enzyme-linked immunosorbent assay, and an immunoblot assay manufactured by Euroimmun, Diesse, and Mikrogen, respectively. Virus neutralization test (VNT) was performed for 99 sera using standard TOSV, sandfly fever Sicilian virus, and sandfly fever Naples virus strains., Results: A total of 89 samples (74.2%) were reactive for TOSV IgG in at least one of the commercial assays, and 31 samples (31.3%) were reactive in VNT for various SFV serotypes. Average percentage agreements among commercial assays and between VNT and the commercial assays were noted as 57.8% and 62.6%, respectively. No significant correlation between assay results and VNT titers was observed. SFV IgM antibodies were detected in a total of eight samples (6.7%) via IIFT, which were nonreactive in enzyme-linked immunosorbent assay and VNT., Discussion: Commercial diagnostic immunoassays displayed slight to fair agreement for TOSV IgG as assessed via kappa and percentage agreement values. The results could only be confirmed via virus neutralization in a portion of the samples, and overall agreement between the commercial assays and VNT was slight. Commercial assays such as immunoblot can be used in addition to VNT for confirmation of TOSV exposure.
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- 2011
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22. [Investigation of dengue virus and yellow fever virus seropositivities in blood donors from Central/Northern Anatolia, Turkey].
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Ergünay K, Saygan MB, Aydoğan S, Litzba N, Niedrig M, Pınar A, and Us D
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- Adult, Antibody Specificity, Antigens, Viral blood, Antigens, Viral immunology, Blood Donors, Enzyme-Linked Immunosorbent Assay, Female, Fluorescent Antibody Technique, Indirect, Humans, Immunoglobulin G blood, Immunoglobulin M blood, Male, Middle Aged, Neutralization Tests, Seroepidemiologic Studies, Turkey epidemiology, Viral Nonstructural Proteins blood, Viral Nonstructural Proteins immunology, Young Adult, Antibodies, Viral blood, Dengue epidemiology, Dengue Virus immunology, Yellow Fever epidemiology, Yellow fever virus immunology
- Abstract
Dengue virus (DENV) and yellow fever virus (YFV) are two of the globally prevalent vector-borne flaviviruses. Data on these viruses from Turkey is limited to a single study originating from the western, Aegean region of Turkey, where evidence for DENV exposure had been confirmed in residents and presence of hemagglutination inhibiting antibodies against YFV had been revealed. The aim of this study was to investigate the rates of seropositivity of DENV and YFV in blood donors from Central/Northern Anatolia, Turkey, for the demonstration of possible human exposure. Serum samples were collected by the Turkish Red Crescent Middle Anatolia Regional Blood Center from donation sites at Ankara, Konya, Eskişehir and Zonguldak provinces and included in the study after informed consent. Ankara is the capital and second most-populated city in Turkey. All samples were previously evaluated for West Nile and tick-borne encephalitis virus antibodies and found to be negative. A total of 2435 and 1502 sera have been evaluated for IgG antibodies against DENV and YFV, respectively. Commercial enzymelinked immunosorbent assays (ELISAs) and indirect immunofluorescence tests (IIFTs) were applied (Euroimmun, Germany) for DENV/YFV IgG surveillance. DENV IgG reactive sera were further evaluated for IgM by ELISA and a commercial mosaic IIFT to determine DENV subtypes. IgM positive samples were also analyzed by a commercial NS1 antigen detection assay (Bio-Rad Laboratories, France). YFV IgG reactive samples were evaluated by IIFT for IgM and via mosaic IIFT and antibody specificity were confirmed by plaque reduction neutralization test (PRNT). Anti-DENV IgGs were demonstrated in repeated assays in 0.9% (21/2435) of the sera. In two samples with borderline IgG results, presence of DENV IgM was detected, one of which was also borderline positive for DENV NS1 antigen. In 14.3% (3/21) of the IgG reactive sera, mosaic IIFT was evaluated as positive and displayed prominent reactivity for DENV-2 in all samples. From five donors with DENV reactivity, new samples were obtained after at least six months which revealed the continuing presence of DENV IgG activity in four. One sample which was initially positive for IgM, borderline for NS1 antigen and borderline for IgG was observed to be positive for IgG and negative for IgM in redonation. IIFT results in three redonation samples also indicated reactivity for DENV-1 and DENV-2 subtypes. Anti-YFV IgGs were detected in 0.6% (9/1502) of the sera. YFV IgM could not be demonstrated in any of the IgG reactive samples and PRNT was evaluated as negative. In conclusion, evidence for DENV exposure, presumably to DENV-2, was identified in residents from Central Anatolian provinces of Ankara and Konya for the first time, however, seroreactivity detected against YFV could not be confirmed by PRNT. These findings indicated that DENV or an antigenically-similar flavivirus was probably present in the study region and sporadic human exposure might have occurred.
- Published
- 2010
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