Genetische Charakterisierung deutscher Schweineinfluenzaviren

Die genetische Variabilität der Influenza-A-Viren ermöglicht es ihnen sowohl Vögel als auch Menschen und Schweine zu infizieren und gefährliche Reassortanten hervorzubringen. Aus diesem Grund ist die genetische Charakterisierung porziner Viren auch aus humanmedizinischer Sicht von großer Bedeutung. Durch die Verwendung der NGS-Technologie von Illumnia wurden im Vergleich zur bisher verwendeten cycle sequencing-Methode folgende Vorteile beobachtet: einen 3fach höheren Durchsatz an zu entschlüsselnden Viren durch die gleichzeitige Sequenzierung von 7 bis 10 Virusisolaten (Multiplex-Sequenzierung) sowie eine deutlich höhere statistische Absicherung der Sequenzabfolge. Die Phylogramme zeigten, dass in Europa, unabhängig zu den nordamerikanischen Schweineviren, drei genetische Linien entstanden sind: die avian-like H1N1-, die human-like H3N2- sowie die human-like H1N2-Linie. Die Daten wiesen ebenso auf eine kontinuierliche Entwicklung innerhalb der europäischen Schweineviren hin, welche durch die Akkumulation von Mutationen verursacht wird. Neben dem Nachweis von wirtsübergreifenden Infektionen (Schwein↔Mensch, Vogel→Mensch und Schwein→Vogel) und Resistenzmutationen konnte auch erstmalig eine neue PB1-F2-Variante von 101 AS detektiert werden. Über die Generierung von Virusrekombinanten bestehend aus dem genetischen Material der H1N1-Viren A/sw/Potsdam/15/81, A/sw/Belzig/2/01 und A/WSN/33 konnte mittels Passagierung der Viren unter Amantadindruck die Entstehung resistenzvermittelnder Mutationen im M2 nachgestellt werden. Neben den bereits publizierten Mutationen V27A, A30T, S31N und G34E wurden folgende bisher unbekannte resistenzvermittelnde AS-Substitutionen identifiziert: A30E und S31F. Auch konnte über die Herstellung Amantadin-sensitiver Viren, welche anstelle von Leucin bzw. Valin für die AS Isoleucin an Position 26 bzw. 27 kodierten, gezeigt werden, dass diese Substitutionen keinen Einfluss auf die Suszeptibilität der Viren gegenüber Amantadin ausübten

Novel ressortant swine H3N2 influenza A viruses in Germany

Analysis of 228 H3N2 swine influenza A virus isolates collected between 2003 and 2015 in Germany revealed important changes in molecular epidemiology. The data indicate that a novel reassortant, Rietberg/2014-like swine H3N2, emerged in February 2014 in Northern Germany. It is comprised of a hemagglutinin gene of seasonal H3N2 (A/Denmark/129/2005-like), a neuraminidase gene of Emmelsbuell/2009-like swine H1N2 and the internal gene cassette of pandemic H1N1 viruses. Together with Danish swine H3N2 strains of 2013–2015 with identical genome layout, the Rietberg/2014-like viruses represent a second swine H3N2 lineage which cocirculates with a variant of the Gent/1984-like swine H3N2 lineage. This variant, named Gent1984/Diepholz-like swine H3N2, has a Gent/1984-like HA and a Diepholz/2008-like NA; the origin of the internal gene cassette likely derived from avian-like swine H1N1. The first isolate of the Gent1984/Diepholz reassortant emerged in Northern Germany in September 2011 whereas the last German Gent/1984-like isolate was collected in October 2011.Peer Reviewe

Cocirculation of Swine H1N1 Influenza A Virus Lineages in Germany

The genome analysis of 328 H1N1 swine influenza virus isolates collected in a 13-year long-term swine influenza surveillance in Germany is reported. Viral genomes were sequenced with the Illumina next-generation sequencing technique and conventional Sanger methods. Phylogenetic analyses were conducted with Bayesian tree inference. The results indicate continued prevalence of Eurasian avian swine H1N1 but also emergence of a novel H1N1 reassortant, named Schneiderkrug/2013-like swine H1N1, with human-like hemagglutinin and avian-like neuraminidase and internal genes. Additionally, the evolution of an antigenic drift variant of A (H1N1) pdm09 was observed, named Wachtum/2014-like swine H1N1. Both variants were first isolated in northwest Germany, spread to neighboring German states and reached greater proportions of the H1N1 isolates of 2014 and 2015. The upsurge of Wachtum/2014-like swine H1N1 is of interest as this is the first documented persistent swine-to-swine spread of A (H1N1) pdm09 in Germany associated with antigenic variation. Present enzootic swine influenza viruses in Germany now include two or more co-circulating, antigenically variant viruses of each of the subtypes, H1N1 and H1N2

Cocirculation of Swine H1N1 Influenza A Virus Lineages in Germany

The genome analysis of 328 H1N1 swine influenza virus isolates collected in a 13-year long-term swine influenza surveillance in Germany is reported. Viral genomes were sequenced with the Illumina next-generation sequencing technique and conventional Sanger methods. Phylogenetic analyses were conducted with Bayesian tree inference. The results indicate continued prevalence of Eurasian avian swine H1N1 but also emergence of a novel H1N1 reassortant, named Schneiderkrug/2013-like swine H1N1, with human-like hemagglutinin and avian-like neuraminidase and internal genes. Additionally, the evolution of an antigenic drift variant of A (H1N1) pdm09 was observed, named Wachtum/2014-like swine H1N1. Both variants were first isolated in northwest Germany, spread to neighboring German states and reached greater proportions of the H1N1 isolates of 2014 and 2015. The upsurge of Wachtum/2014-like swine H1N1 is of interest as this is the first documented persistent swine-to-swine spread of A (H1N1) pdm09 in Germany associated with antigenic variation. Present enzootic swine influenza viruses in Germany now include two or more co-circulating, antigenically variant viruses of each of the subtypes, H1N1 and H1N2

Characterization of a novel picornavirus isolate from a diseased European eel (Anguilla anguilla)

A novel picornavirus was isolated from specimens of a diseased European eel (Anguilla anguilla). This virus induced a cytopathic effect in eel embryonic kidney cells and high mortality in a controlled transmission study using elvers. Eel picornavirus has a genome of 7,496 nucleotides that encodes a polyprotein of 2,259 amino acids. It has a typical picornavirus genome layout, but its low similarity to known viral proteins suggests a novel species in the family Picornaviridae