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The main findings of the post-mortem examination of poultry infected with highly pathogenic avian influenza viruses (HPAIV) include necrotizing inflammation and viral antigen in multiple organs. The lesion profile displays marked variability, depending on viral subtype, strain, and host species. Therefore, in this study, a semiquantitative scoring system was developed to compare histopathological findings across a wide range of study conditions. Briefly, the severity of necrotizing lesions in brain, heart, lung, liver, kidney, pancreas, and/or lymphocytic depletion in the spleen is scored on an ordinal four-step scale (0 = unchanged, 1 = mild, 2 = moderate, 3 = severe), and the distribution of the viral antigen in parenchymal and endothelial cells is evaluated on a four-step scale (0 = none, 1 = focal, 2 = multifocal, 3 = diffuse). These scores are used for a meta-analysis of experimental infections with H7N7 and H5N8 (clade 2.3.4.4b) HPAIV in chickens, turkeys, and ducks. The meta-analysis highlights the rather unique endotheliotropism of these HPAIV in chickens and a more severe necrotizing encephalitis in H7N7-HPAIV-infected turkeys. In conclusion, the proposed scoring system can be used to condensate HPAIV-typical pathohistological findings into semiquantitative data, thus enabling systematic phenotyping of virus strains and their tissue tropism.
Maria Landmann; David Scheibner; Annika Graaf; Marcel Gischke; Susanne Koethe; Olanrewaju Fatola; Barbara Raddatz; Thomas Mettenleiter; Martin Beer; Christian Grund; Timm Harder; Elsayed Abdelwhab; Reiner Ulrich. A Semiquantitative Scoring System for Histopathological and Immunohistochemical Assessment of Lesions and Tissue Tropism in Avian Influenza. Viruses 2021, 13, 868 .
AMA StyleMaria Landmann, David Scheibner, Annika Graaf, Marcel Gischke, Susanne Koethe, Olanrewaju Fatola, Barbara Raddatz, Thomas Mettenleiter, Martin Beer, Christian Grund, Timm Harder, Elsayed Abdelwhab, Reiner Ulrich. A Semiquantitative Scoring System for Histopathological and Immunohistochemical Assessment of Lesions and Tissue Tropism in Avian Influenza. Viruses. 2021; 13 (5):868.
Chicago/Turabian StyleMaria Landmann; David Scheibner; Annika Graaf; Marcel Gischke; Susanne Koethe; Olanrewaju Fatola; Barbara Raddatz; Thomas Mettenleiter; Martin Beer; Christian Grund; Timm Harder; Elsayed Abdelwhab; Reiner Ulrich. 2021. "A Semiquantitative Scoring System for Histopathological and Immunohistochemical Assessment of Lesions and Tissue Tropism in Avian Influenza." Viruses 13, no. 5: 868.
Newcastle disease (ND), caused by avian orthoavulavirus type‐1 (NDV), is endemic in poultry in many regions of the world and causes continuing outbreaks in poultry populations. In the Middle East, genotype XXI, , used to be present in poultry in Egypt but has been replaced by genotype VII. We investigated whether virus evolution contributed to superseding and focused on the antigenic sites within the Hemagglutinin‐Neuraminidase (HN) spike protein. Full length sequences of an NDV genotype VII isolate currently circulating in Egypt was compared to a genotype XXI isolate that was present as co‐infection with vaccine type viruses (II) in a historical virus isolated in 2011. Amino acid differences in the HN glycoprotein for both XXI and VII viruses amounted to 11.7% and 11.9 %, respectively, compared to the La Sota vaccine type. However, mutations within the globular head (aa 126‐570), bearing relevant antigenic sites, were underrepresented (aa divergence of 8.8% and 8.1 % compared to 22.4% and 25.6% within the protein domains encompassing cytoplasmic tail, transmembrane part and stalk regions (aa 1‐125) for genotypes XXI and VII, respectively). Nevertheless, reaction patterns of HN‐specific monoclonal antibodies inhibiting receptor binding revealed differences between vaccine type viruses and genotype XXI and VII viruses for epitopes located in the head domain. Accordingly, compared to Egyptian vaccine type isolates and the La Sota vaccine reference strain, single aa substitutions in 6 of 10 described neutralizing epitopes of HN were found. However, the same alterations in neutralization sensitive epitopes were present in old genotype XXI as well as in newly emerged genotype VII isolates. In addition, isolates were indistinguishable by polyclonal chicken sera raised against different genotypes including vaccine viruses. These findings suggest that factors other than antigenic differences within the HN protein account for facilitating the spread of genotype VII versus genotype XXI viruses in Egypt.
Mahmoud M. Naguib; Dirk Höper; Magdy F. Elkady; Manal A. Afifi; Ahmed Erfan; Hassanein H. Abozeid; Wafaa M. Hasan; Abdel‐Satar Arafa; Momtaz Shahein; Martin Beer; Timm C. Harder; Christian Grund. Comparison of genomic and antigenic properties of Newcastle Disease virus genotypes II, XXI and VII from Egypt do not point to antigenic drift as selection marker. Transboundary and Emerging Diseases 2021, 1 .
AMA StyleMahmoud M. Naguib, Dirk Höper, Magdy F. Elkady, Manal A. Afifi, Ahmed Erfan, Hassanein H. Abozeid, Wafaa M. Hasan, Abdel‐Satar Arafa, Momtaz Shahein, Martin Beer, Timm C. Harder, Christian Grund. Comparison of genomic and antigenic properties of Newcastle Disease virus genotypes II, XXI and VII from Egypt do not point to antigenic drift as selection marker. Transboundary and Emerging Diseases. 2021; ():1.
Chicago/Turabian StyleMahmoud M. Naguib; Dirk Höper; Magdy F. Elkady; Manal A. Afifi; Ahmed Erfan; Hassanein H. Abozeid; Wafaa M. Hasan; Abdel‐Satar Arafa; Momtaz Shahein; Martin Beer; Timm C. Harder; Christian Grund. 2021. "Comparison of genomic and antigenic properties of Newcastle Disease virus genotypes II, XXI and VII from Egypt do not point to antigenic drift as selection marker." Transboundary and Emerging Diseases , no. : 1.
Repeated outbreaks due to H3N1 low pathogenicity avian influenza viruses (LPAIV) in Belgium were associated with unusually high mortality in chicken in 2019. Those events caused considerable economic losses and prompted restriction measures normally implemented for eradicating high pathogenicity avian influenza viruses (HPAIV). Initial pathology investigations and infection studies suggested this virus to be able to replicate systemically, being very atypical for H3 LPAIV. Here, we investigate the pathogenesis of this H3N1 virus and propose a mechanism explaining its unusual systemic replication capability. By intravenous and intracerebral inoculation in chicken, we demonstrate systemic spread of this virus, extending to the central nervous system. Endoproteolytic viral hemagglutinin (HA) protein activation by either tissue-restricted serine peptidases or ubiquitous subtilisin-like proteases is the functional hallmark distinguishing (H5 or H7) LPAIV from HPAIV. However, luciferase reporter assays show that HA cleavage in case of the H3N1 strain in contrast to the HPAIV is not processed by intracellular proteases. Yet the H3N1 virus replicates efficiently in cell culture without trypsin, unlike LPAIVs. Moreover, this trypsin-independent virus replication is inhibited by 6-aminohexanoic acid, a plasmin inhibitor. Correspondingly, in silico analysis indicates that plasminogen is recruitable by the viral neuraminidase for proteolytic activation due to the loss of a strongly conserved N-glycosylation site at position 130. This mutation was shown responsible for plasminogen recruitment and neurovirulence of the mouse brain-passaged laboratory strain A/WSN/33 (H1N1). In conclusion, our findings provide good evidence in natural chicken strains for N1 neuraminidase-operated recruitment of plasminogen, enabling systemic replication leading to an unusual high pathogenicity phenotype. Such a gain of function in naturally occurring AIVs representing an established human influenza HA-subtype raises concerns over potential zoonotic threats.
Jacob Schön; ANGELE Breithaupt; Dirk Höper; Jacqueline King; Anne Pohlmann; Rokshana Parvin; Klaus-Peter Behr; Bernd-Andreas Schwarz; Martin Beer; Jürgen Stech; Timm Harder; Christian Grund. Neuraminidase-associated plasminogen recruitment enables systemic spread of natural avian Influenza viruses H3N1. PLOS Pathogens 2021, 17, e1009490 .
AMA StyleJacob Schön, ANGELE Breithaupt, Dirk Höper, Jacqueline King, Anne Pohlmann, Rokshana Parvin, Klaus-Peter Behr, Bernd-Andreas Schwarz, Martin Beer, Jürgen Stech, Timm Harder, Christian Grund. Neuraminidase-associated plasminogen recruitment enables systemic spread of natural avian Influenza viruses H3N1. PLOS Pathogens. 2021; 17 (4):e1009490.
Chicago/Turabian StyleJacob Schön; ANGELE Breithaupt; Dirk Höper; Jacqueline King; Anne Pohlmann; Rokshana Parvin; Klaus-Peter Behr; Bernd-Andreas Schwarz; Martin Beer; Jürgen Stech; Timm Harder; Christian Grund. 2021. "Neuraminidase-associated plasminogen recruitment enables systemic spread of natural avian Influenza viruses H3N1." PLOS Pathogens 17, no. 4: e1009490.
The H5 A/Goose/Guangdong/1/1996 (gs/GD) lineage emerged in China in 1996. Rooted in the respective gs/GD lineage, the hemagglutinin (HA) gene of highly pathogenic avian influenza viruses (HPAIV) has genetically diversified into a plethora of clades and subclades and evolved into an assortment of sub‐ and genotypes. Some caused substantial losses in the poultry industry and had a major impact on wild bird populations alongside public health implications due to a zoonotic potential of certain clades. After the primary introduction of the HPAI H5N1 gs/GD lineage into Europe in autumn 2005 and winter 2005/2006, Germany has seen recurring incursions of four varying H5Nx subtypes (H5N1, H5N8, H5N5, H5N6) carrying multiple distinct reassortants, all descendants of the gs/GD virus. The first HPAIV H5 epidemic in Germany during 2006/2007 was caused by a clade 2.2 subtype H5N1 virus. Phylogenetic analysis confirmed three distinct clusters belonging to clades 2.2.1, 2.2.2 and 2.2, concurring with geographic and temporal structures. From 2014 onwards, HPAIV clade 2.3.4.4 has dominated the epidemiological situation in Germany. The initial clade 2.3.4.4a HPAIV H5N8, reaching Germany in November 2014, caused a limited epidemic affecting five poultry holdings, one zoo in Northern Germany and few wild birds. After November 2016, HPAIV of clade 2.3.4.4b have dominated the situation to date. The most extensive HPAIV H5 epidemic on record reached Germany in winter 2016/2017, encompassing multiple incursion events with two subtypes (H5N8, H5N5) and entailing five reassortants. A novel H5N6 clade 2.3.4.4b strain affected Germany from December 2017 onwards, instigating low‐level infection in smallholdings and wild birds. Recently, in spring 2020, a novel incursion of a genetically distinct HPAI clade 2.3.4.4b H5N8 virus caused another epidemic in Europe, which affected a small number of poultry holdings, one zoo and two wild birds throughout Germany.
Jacqueline King; Timm Harder; Franz J. Conraths; Martin Beer; Anne Pohlmann. The genetics of highly pathogenic avian influenza viruses of subtype H5 in Germany, 2006–2020. Transboundary and Emerging Diseases 2020, 68, 1136 -1150.
AMA StyleJacqueline King, Timm Harder, Franz J. Conraths, Martin Beer, Anne Pohlmann. The genetics of highly pathogenic avian influenza viruses of subtype H5 in Germany, 2006–2020. Transboundary and Emerging Diseases. 2020; 68 (3):1136-1150.
Chicago/Turabian StyleJacqueline King; Timm Harder; Franz J. Conraths; Martin Beer; Anne Pohlmann. 2020. "The genetics of highly pathogenic avian influenza viruses of subtype H5 in Germany, 2006–2020." Transboundary and Emerging Diseases 68, no. 3: 1136-1150.
Swine influenza A viruses (swIAVs) can play a crucial role in the generation of new human pandemic viruses. In this study, in-depth passive surveillance comprising nearly 2,500 European swine holdings and more than 18,000 individual samples identified a year-round presence of up to four major swIAV lineages on more than 50% of farms surveilled. Phylogenetic analyses show that intensive reassortment with human pandemic A(H1N1)/2009 (H1pdm) virus produced an expanding and novel repertoire of at least 31 distinct swIAV genotypes and 12 distinct hemagglutinin/neuraminidase combinations with largely unknown consequences for virulence and host tropism. Several viral isolates were resistant to the human antiviral MxA protein, a prerequisite for zoonotic transmission and stable introduction into human populations. A pronounced antigenic variation was noted in swIAV, and several H1pdm lineages antigenically distinct from current seasonal human H1pdm co-circulate in swine. Thus, European swine populations represent reservoirs for emerging IAV strains with zoonotic and, possibly, pre-pandemic potential.
Dinah Henritzi; Philipp Peter Petric; Nicola Sarah Lewis; Annika Graaf; Alberto Pessia; Elke Starick; ANGELE Breithaupt; Günter Strebelow; Christine Luttermann; Larissa Mareike Kristin Parker; Charlotte Schröder; Bärbel Hammerschmidt; Georg Herrler; Elisabeth Große Beilage; Daniel Stadlbauer; Viviana Simon; Florian Krammer; Silke Wacheck; Stefan Pesch; Martin Schwemmle; Martin Beer; Timm Clemens Harder. Surveillance of European Domestic Pig Populations Identifies an Emerging Reservoir of Potentially Zoonotic Swine Influenza A Viruses. Cell Host & Microbe 2020, 28, 614 -627.e6.
AMA StyleDinah Henritzi, Philipp Peter Petric, Nicola Sarah Lewis, Annika Graaf, Alberto Pessia, Elke Starick, ANGELE Breithaupt, Günter Strebelow, Christine Luttermann, Larissa Mareike Kristin Parker, Charlotte Schröder, Bärbel Hammerschmidt, Georg Herrler, Elisabeth Große Beilage, Daniel Stadlbauer, Viviana Simon, Florian Krammer, Silke Wacheck, Stefan Pesch, Martin Schwemmle, Martin Beer, Timm Clemens Harder. Surveillance of European Domestic Pig Populations Identifies an Emerging Reservoir of Potentially Zoonotic Swine Influenza A Viruses. Cell Host & Microbe. 2020; 28 (4):614-627.e6.
Chicago/Turabian StyleDinah Henritzi; Philipp Peter Petric; Nicola Sarah Lewis; Annika Graaf; Alberto Pessia; Elke Starick; ANGELE Breithaupt; Günter Strebelow; Christine Luttermann; Larissa Mareike Kristin Parker; Charlotte Schröder; Bärbel Hammerschmidt; Georg Herrler; Elisabeth Große Beilage; Daniel Stadlbauer; Viviana Simon; Florian Krammer; Silke Wacheck; Stefan Pesch; Martin Schwemmle; Martin Beer; Timm Clemens Harder. 2020. "Surveillance of European Domestic Pig Populations Identifies an Emerging Reservoir of Potentially Zoonotic Swine Influenza A Viruses." Cell Host & Microbe 28, no. 4: 614-627.e6.
Avian influenza virus (AIV) remains a huge challenge for poultry production with negative repercussions for micro- and macro-economy and public health in Bangladesh. High (HP) H5N1 and low pathogenicity (LP) H9N2 AIV are currently endemic in poultry, and both have been reported to infect humans sporadically. Multiple virus introductions of different clades of HPAIV H5N1, reassorted genotypes, and on-going diversification of LPAIV H9N2 create a highly volatile virological environment which potentially implicates increased virulence, adaptation to new host species, and subsequent zoonotic transmission. Allotropy of poultry rearing systems and supply chains further increase the risk of virus spreading, which leads to human exposure and fosters the emergence of new potentially pre-pandemic virus strains. Here, we review the epidemiology, focusing on (i) risk factors for virus spreading, (ii) viral genetic evolution, and (iii) options for AIV control in Bangladesh. It is concluded that improved control strategies would profit from the integration of various intervention tools, including effective vaccination, enhanced biosecurity practice, and improved awareness of producers and traders, although widespread household poultry rearing significantly interferes with any such strategies. Nevertheless, continuous surveillance associated with rapid diagnosis and thorough virus characterization is the basis of such strategies.
Rokshana Parvin; Mohammed Nooruzzaman; Congriev Kumar Kabiraj; Jahan Ara Begum; Emdadul Haque Chowdhury; Mohammad Rafiqul Islam; Timm Harder. Controlling Avian Influenza Virus in Bangladesh: Challenges and Recommendations. Viruses 2020, 12, 751 .
AMA StyleRokshana Parvin, Mohammed Nooruzzaman, Congriev Kumar Kabiraj, Jahan Ara Begum, Emdadul Haque Chowdhury, Mohammad Rafiqul Islam, Timm Harder. Controlling Avian Influenza Virus in Bangladesh: Challenges and Recommendations. Viruses. 2020; 12 (7):751.
Chicago/Turabian StyleRokshana Parvin; Mohammed Nooruzzaman; Congriev Kumar Kabiraj; Jahan Ara Begum; Emdadul Haque Chowdhury; Mohammad Rafiqul Islam; Timm Harder. 2020. "Controlling Avian Influenza Virus in Bangladesh: Challenges and Recommendations." Viruses 12, no. 7: 751.
Infectious bronchitis virus (IBV), a gamma-coronavirus, causes infectious bronchitis (IB), a major respiratory disease of chicken. Its high mutation rate in conjunction with recombination of the RNA genome constantly creates IBV variants that are difficult to control by currently available vaccines. In this study, we addressed the question whether small-scale holdings might harbor IBV variants that serve as a reservoir for newly emerging variants. Egyptian IBV isolate EGY/NR725/2016 (NR725/16) from a small-scale broiler farm was assigned to genotype I, clade 23 (S1:GI-23), based on partial S1 gene sequences and corroborated by full genome sequencing. Analysis of the S1 gene established three subclades for historical IBV strains (S1:GI-23.1, S1:GI-23.2.1 and S1:GI-23.2.2) and confirmed NR725/16 as being part of a separate fourth subclade (S1:GI-23.3). Samples from the years 2018 and 2019 revealed that the new subclade prevails in Egypt, carrying fixed mutations within the hypervariable regions (HVR) 1-3 of the S1 protein that affect two neutralization sensitive epitopes at sites 294F, 297S and 306Y (48.2) and 329R (62.1). In addition, recombination was recognized in isolate NR 725/16, with intra-subtype mixing for the entire genes 3ab and E and inter-subtype mixing for the entire gene 6b with a close match to QX like viruses of genotype GI-19. Further analysis of gene 3ab detected the homologous gene pool to NR725/16 in samples from 2013 (3ab:C) and closely related 3ab genotypes in IBV Egyptian isolates from 2016, 2018 and 2019. These data prove a flourishing exchange between poultry holdings with a common gene pool. The continued circulation of viruses harboring genes S1:GI-23.3 and 3ab:C indicates an evolutionary advantage of this combination possibly by combining antigenic escape with modulated pathogenicity to facilitate IBV spread in the vaccinated poultry population in Egypt.
Ibrahim Moharam; Hesham Sultan; K. Hassan; Mahmoud Ibrahim; Salama Shany; Awad A. Shehata; Mohammed AboElkhair; Florian Pfaff; Dirk Höper; Magdy EL Kady; Martin Beer; Timm Harder; Hafez Hafez; Christian Grund. Emerging infectious bronchitis virus (IBV) in Egypt: Evidence for an evolutionary advantage of a new S1 variant with a unique gene 3ab constellation. Infection, Genetics and Evolution 2020, 85, 104433 -104433.
AMA StyleIbrahim Moharam, Hesham Sultan, K. Hassan, Mahmoud Ibrahim, Salama Shany, Awad A. Shehata, Mohammed AboElkhair, Florian Pfaff, Dirk Höper, Magdy EL Kady, Martin Beer, Timm Harder, Hafez Hafez, Christian Grund. Emerging infectious bronchitis virus (IBV) in Egypt: Evidence for an evolutionary advantage of a new S1 variant with a unique gene 3ab constellation. Infection, Genetics and Evolution. 2020; 85 ():104433-104433.
Chicago/Turabian StyleIbrahim Moharam; Hesham Sultan; K. Hassan; Mahmoud Ibrahim; Salama Shany; Awad A. Shehata; Mohammed AboElkhair; Florian Pfaff; Dirk Höper; Magdy EL Kady; Martin Beer; Timm Harder; Hafez Hafez; Christian Grund. 2020. "Emerging infectious bronchitis virus (IBV) in Egypt: Evidence for an evolutionary advantage of a new S1 variant with a unique gene 3ab constellation." Infection, Genetics and Evolution 85, no. : 104433-104433.
Highly pathogenic (HP) H5N1, clade 2.2.1, and low pathogenic avian influenza (LPAI) H9N2 viruses, G1-B lineage, are endemic in poultry in Egypt and have co-circulated for almost a decade. Surprisingly, no inter-subtypic reassortment events have been reported from the field during that time. After the introduction of HPAIV H5N8, clade 2.3.4.4b, in Egyptian poultry in 2016, suddenly HP H5N2 reassortants with H9N2 viruses emerged. The current analyses focussed on studying 32 duck flocks, 4 broiler chicken flocks, and 1 turkey flock, suffering from respiratory manifestations with moderate to high mortality reared in two Egyptian governorates during 2019. Real-time RT-PCR substantiated the presence of HP H5N8 in 21 of the 37 investigated flocks with mixed infection of H9N2 in two of them. HP H5N1 was not detected. Full hemagglutinin (HA) sequencing of 10 samples with full-genome sequencing of three of them revealed presence of a single genotype. Very few substituting mutations in the HA protein were detected versus previous Egyptian HA sequences of that clade. Interestingly, amino acid substitutions in the Matrix (M2) and the Neuraminidase (NA) proteins associated with conferring both Amantadine and Oseltamivir resistance were present. Systematic reassortment analysis of all publicly available Egyptian whole genome sequences of HP H5N8 (n = 23), reassortant HP H5N2 (n = 2) and LP H9N2 (n = 53) viruses revealed presence of at least seven different genotypes of HPAI H5Nx viruses of clade 2.3.4.4b in Egypt since 2016. For H9N2 viruses, at least three genotypes were distinguishable. Heat mapping and tanglegram analyses suggested that several internal gene segments in both HP H5Nx and H9N2 viruses originated from avian influenza viruses circulating in wild bird species in Egypt. Based on the limited set of whole genome sequences available, annual replacement patterns of HP H5Nx genotypes emerged and suggested selective advantages of certain genotypes since 2016.
Kareem E. Hassan; Noha Saad; Hassanein H. Abozeid; Salama Shany; Magdy F. El-Kady; Abdelsatar Arafa; Azza A.A. El-Sawah; Florian Pfaff; Hafez M. Hafez; Martin Beer; Timm Harder. Genotyping and reassortment analysis of highly pathogenic avian influenza viruses H5N8 and H5N2 from Egypt reveals successive annual replacement of genotypes. Infection, Genetics and Evolution 2020, 84, 104375 .
AMA StyleKareem E. Hassan, Noha Saad, Hassanein H. Abozeid, Salama Shany, Magdy F. El-Kady, Abdelsatar Arafa, Azza A.A. El-Sawah, Florian Pfaff, Hafez M. Hafez, Martin Beer, Timm Harder. Genotyping and reassortment analysis of highly pathogenic avian influenza viruses H5N8 and H5N2 from Egypt reveals successive annual replacement of genotypes. Infection, Genetics and Evolution. 2020; 84 ():104375.
Chicago/Turabian StyleKareem E. Hassan; Noha Saad; Hassanein H. Abozeid; Salama Shany; Magdy F. El-Kady; Abdelsatar Arafa; Azza A.A. El-Sawah; Florian Pfaff; Hafez M. Hafez; Martin Beer; Timm Harder. 2020. "Genotyping and reassortment analysis of highly pathogenic avian influenza viruses H5N8 and H5N2 from Egypt reveals successive annual replacement of genotypes." Infection, Genetics and Evolution 84, no. : 104375.
Domestic waterfowl plays an important role in the perpetuation and transmission of avian pathogens including avian influenza viruses (AIV) of low and high pathogenicity, which pose severe economic and public health concerns in Bangladesh. This study focused on active surveillance of several avian viral pathogens with a special reference to AIV in selected backyard duck populations in Bangladesh. A total of 500 pooled oropharyngeal and cloacal samples from individual ducks of four districts were tested by real time PCRs for the presence of AIV, avian avulavirus-1, anatid herpesvirus-1, avian parvovirus, avian bornavirus and avian coronavirus. The investigation identified 27 (5.4%) ducks positive for AIV and 12 (2.4%) for avian coronavirus. In 13 samples, RNA specific for AIV H4N6 was detected. Phylogenetic analysis of the AIV hemagglutinin H4 and neuraminidase N6 genes suggested a clustering of Bangladeshi AIV H4N6 in Eurasian lineage group 2. Other AIV positive sample had very low virus loads (Cq >36) and were not subtyped. Coronaviral sequences of a fragment of the polymerase gene were related to Eurasian-Australian duck gamma-coronaviruses. Our current active surveillance in free-range domestic backyard ducks in Bangladesh failed to detect highly pathogenic (HP) AIV in contrast to our previous passive monitoring study. Nevertheless, active monitoring of domestic duck populations may be important to highlight presence and transmission dynamics of economically less important AIV that still may serve as reassortment partners for the generation of new HP and zoonotic AIV. Research highlights
Rokshana Parvin; Congriev Kumar Kabiraj; Tanjin Tamanna Mumu; Emdadul Haque Chowdhury; Mohammad Rafiqul Islam; Martin Beer; Timm Harder. Active virological surveillance in backyard ducks in Bangladesh: detection of avian influenza and gammacoronaviruses. Avian Pathology 2020, 49, 361 -368.
AMA StyleRokshana Parvin, Congriev Kumar Kabiraj, Tanjin Tamanna Mumu, Emdadul Haque Chowdhury, Mohammad Rafiqul Islam, Martin Beer, Timm Harder. Active virological surveillance in backyard ducks in Bangladesh: detection of avian influenza and gammacoronaviruses. Avian Pathology. 2020; 49 (4):361-368.
Chicago/Turabian StyleRokshana Parvin; Congriev Kumar Kabiraj; Tanjin Tamanna Mumu; Emdadul Haque Chowdhury; Mohammad Rafiqul Islam; Martin Beer; Timm Harder. 2020. "Active virological surveillance in backyard ducks in Bangladesh: detection of avian influenza and gammacoronaviruses." Avian Pathology 49, no. 4: 361-368.
An intravenous pathogenicity index (IVPI) of > 1.2 in chickens or, in case of subtypes H5 and H7, expression of a polybasic hemagglutinin cleavage site (HACS), signals high pathogenicity (HP). Viruses of the H9N2-G1 lineage, which spread across Asia and Africa, are classified to be of low pathogenicity although, in the field, they became associated with severe clinical signs and epizootics in chickens. Here we report on a pre-eminent trait of recent H9N2-G1 isolates from Bangladesh and India, which express a tribasic HACS (motif PAKSKR-GLF; reminiscent of an HPAIV-like polybasic HACS) and compare their features to H9Nx viruses with di- and monobasic HACS from other phylogenetic and geographic origins. In an in vitro assay, the tribasic HACS of H9N2 was processed by furin-like proteases similar to bona fide H5 HPAIV while some dibasic sites showed increased cleavability but monobasic HACS none. Yet, all viruses remained trypsin-dependent in cell culture. In ovo, only tribasic H9N2 viruses were found to replicate in a grossly extended spectrum of embryonic organs. In contrast to all subtype H5/H7 HPAI viruses, tribasic H9N2 viruses did not replicate in endothelial cells either in the chorio-allantoic membrane or in other embryonic tissues. By IVPI, all H9Nx isolates proved to be of low pathogenicity. Pathogenicity assessment of tribasic H9N2-G1 viruses remains problematic. It cannot be excluded that the formation of a third basic amino acid in the HACS forms an intermediate step towards a gain in pathogenicity. Continued observation of the evolution of these viruses in the field is recommended.
Rokshana Parvin; Jan Schinkoethe; Christian Grund; Reiner Ulrich; Franziska Bönte; Klaus P. Behr; Matthias Voss; Mohammed A. Samad; Kareem Hassan; Christine Luttermann; Martin Beer; Timm Harder. Comparison of pathogenicity of subtype H9 avian influenza wild-type viruses from a wide geographic origin expressing mono-, di-, or tri-basic hemagglutinin cleavage sites. Veterinary Research 2020, 51, 1 -12.
AMA StyleRokshana Parvin, Jan Schinkoethe, Christian Grund, Reiner Ulrich, Franziska Bönte, Klaus P. Behr, Matthias Voss, Mohammed A. Samad, Kareem Hassan, Christine Luttermann, Martin Beer, Timm Harder. Comparison of pathogenicity of subtype H9 avian influenza wild-type viruses from a wide geographic origin expressing mono-, di-, or tri-basic hemagglutinin cleavage sites. Veterinary Research. 2020; 51 (1):1-12.
Chicago/Turabian StyleRokshana Parvin; Jan Schinkoethe; Christian Grund; Reiner Ulrich; Franziska Bönte; Klaus P. Behr; Matthias Voss; Mohammed A. Samad; Kareem Hassan; Christine Luttermann; Martin Beer; Timm Harder. 2020. "Comparison of pathogenicity of subtype H9 avian influenza wild-type viruses from a wide geographic origin expressing mono-, di-, or tri-basic hemagglutinin cleavage sites." Veterinary Research 51, no. 1: 1-12.
A novel H5N8 highly pathogenic avian influenza virus (HPAIV) was detected in a greater white-fronted goose in January 2020 in Brandenburg, Germany, and, in February 2020, in domestic chickens belonging to a smallholding in Baden-Wuerttemberg, Germany. Full-genome sequencing was conducted on the MinION platform, enabling further phylogenetic analyses. The virus of clade 2.3.4.4b holds six segments from a Eurasian/Asian/African HPAIV H5N8 reassortant and two segments from low pathogenic avian influenza H3N8 subtype viruses recently detected in wild birds in Central Russia. These new entries continue to show the reassortment potential of the clade 2.3.4.4 H5Nx viruses, underlining the necessity for full-genome sequencing and continuous surveillance.
Jacqueline King; Christoph Schulze; Andreas Engelhardt; Andreas Hlinak; Sara-Lisa Lennermann; Kerstin Rigbers; Jasmin Skuballa; Christoph Staubach; Thomas C. Mettenleiter; Timm Harder; Martin Beer; Anne Pohlmann. Novel HPAIV H5N8 Reassortant (Clade 2.3.4.4b) Detected in Germany. Viruses 2020, 12, 281 .
AMA StyleJacqueline King, Christoph Schulze, Andreas Engelhardt, Andreas Hlinak, Sara-Lisa Lennermann, Kerstin Rigbers, Jasmin Skuballa, Christoph Staubach, Thomas C. Mettenleiter, Timm Harder, Martin Beer, Anne Pohlmann. Novel HPAIV H5N8 Reassortant (Clade 2.3.4.4b) Detected in Germany. Viruses. 2020; 12 (3):281.
Chicago/Turabian StyleJacqueline King; Christoph Schulze; Andreas Engelhardt; Andreas Hlinak; Sara-Lisa Lennermann; Kerstin Rigbers; Jasmin Skuballa; Christoph Staubach; Thomas C. Mettenleiter; Timm Harder; Martin Beer; Anne Pohlmann. 2020. "Novel HPAIV H5N8 Reassortant (Clade 2.3.4.4b) Detected in Germany." Viruses 12, no. 3: 281.
We detected a novel reassortant highly pathogenic avian influenza A(H5N2) virus in 3 poultry farms in Egypt. The virus carried genome segments of a pigeon H9N2 influenza virus detected in 2014, a nucleoprotein segment of contemporary chicken H9N2 viruses from Egypt, and hemagglutinin derived from the 2.3.4.4b H5N8 virus clade.
Kareem Hassan; Jacqueline King; Magdy El-Kady; Manal Afifi; Hassanein Abozeid; Anne Pohlmann; Martin Beer; Timm Harder. Novel Reassortant Highly Pathogenic Avian Influenza A(H5N2) Virus in Broiler Chickens, Egypt. Emerging Infectious Diseases 2020, 26, 129 -133.
AMA StyleKareem Hassan, Jacqueline King, Magdy El-Kady, Manal Afifi, Hassanein Abozeid, Anne Pohlmann, Martin Beer, Timm Harder. Novel Reassortant Highly Pathogenic Avian Influenza A(H5N2) Virus in Broiler Chickens, Egypt. Emerging Infectious Diseases. 2020; 26 (1):129-133.
Chicago/Turabian StyleKareem Hassan; Jacqueline King; Magdy El-Kady; Manal Afifi; Hassanein Abozeid; Anne Pohlmann; Martin Beer; Timm Harder. 2020. "Novel Reassortant Highly Pathogenic Avian Influenza A(H5N2) Virus in Broiler Chickens, Egypt." Emerging Infectious Diseases 26, no. 1: 129-133.
For several years, poultry production in Egypt has been suffering from co-circulation of multiple respiratory viruses including highly pathogenic avian influenza virus (HPAIV) H5N1 (clade 2.2.1.2) and low pathogenic H9N2 (clade G1-B). Incursion of HPAIV H5N8 (clade 2.3.4.4b) to Egypt in November 2016 via wild birds followed by spread into commercial poultry flocks further complicated the situation. Current analyses focussed on 39 poultry farms suffering from respiratory manifestation and high mortality in six Egyptian governorates during 2017-2018. Real-time RT-PCR (RT-qPCR) substantiated the co-presence of at least two respiratory virus species in more than 80% of the investigated flocks. The percentage of HPAIV H5N1-positive holdings was fairly stable in 2017 (12.8%) and 2018 (10.2%), while the percentage of HPAIV H5N8-positive holdings increased from 23% in 2017 to 66.6% during 2018. The proportion of H9N2-positive samples was constantly high (2017:100% and 2018:63%), and H9N2 co-circulated with HPAIV H5N8 in 22 out of 39 (56.8%) flocks. Analyses of 26 H5, 18 H9 and 4 N2 new sequences confirmed continuous genetic diversification. In silico analysis revealed numerous amino acid substitutions in the HA and NA proteins suggestive of increased adaptation to mammalian hosts and putative antigenic variation. For sensitive detection of H9N2 viruses by RT-qPCR, an update of primers and probe sequences was crucial. Reasons for the relative increase of HPAIV H5N8 infections versus H5N1 remained unclear, but lack of suitable vaccines against clade 2.3.4.4b cannot be excluded. A reconsideration of surveillance and control measures should include updating of diagnostic tools and vaccination strategies.
Kareem E. Hassan; Magdy F. El‐Kady; Azza A. A. El‐Sawah; Christine Luttermann; Rokshana Parvin; Salama Shany; Martin Beer; Timm Harder. Respiratory disease due to mixed viral infections in poultry flocks in Egypt between 2017 and 2018: Upsurge of highly pathogenic avian influenza virus subtype H5N8 since 2018. Transboundary and Emerging Diseases 2019, 68, 21 -36.
AMA StyleKareem E. Hassan, Magdy F. El‐Kady, Azza A. A. El‐Sawah, Christine Luttermann, Rokshana Parvin, Salama Shany, Martin Beer, Timm Harder. Respiratory disease due to mixed viral infections in poultry flocks in Egypt between 2017 and 2018: Upsurge of highly pathogenic avian influenza virus subtype H5N8 since 2018. Transboundary and Emerging Diseases. 2019; 68 (1):21-36.
Chicago/Turabian StyleKareem E. Hassan; Magdy F. El‐Kady; Azza A. A. El‐Sawah; Christine Luttermann; Rokshana Parvin; Salama Shany; Martin Beer; Timm Harder. 2019. "Respiratory disease due to mixed viral infections in poultry flocks in Egypt between 2017 and 2018: Upsurge of highly pathogenic avian influenza virus subtype H5N8 since 2018." Transboundary and Emerging Diseases 68, no. 1: 21-36.
Endemic co-circulation of potentially zoonotic avian influenza viruses (AIV) of subtypes H5N1 and H9N2 (G1 lineage) in poultry in Bangladesh accelerated diversifying evolution. Two clinical samples from poultry obtained in 2016 yielded five different subtypes (highly pathogenic [HP] H5N1, HP H5N2, HP H7N1, HP H7N2, H9N2) and eight genotypes of AIV by plaque purification. H5 sequences grouped with clade 2.3.2.1a viruses while N1 was related to an older, preceding clade, 2.2.2. The internal genome segments of the plaque-purified viruses originated from clade 2.2.2 of H5N1 or from G1/H9N2 viruses. H9 and N2 segments clustered with contemporary H9N2 strains. In addition, HP H7 sequences were detected for the first time in samples and linked to Pakistani HP H7N3 viruses of 2003. The unexpected findings of mixtures of reassorted HP H5N1 and G1-like H9N2 viruses, which carry genome segments of older clades in association with the detection of HP H7 HA segments calls for confirmation of these results by targeted surveillance in the area of origin of the investigated samples. Hidden niches and obscured transmission pathways may exist that retain or re-introduce genome segments of older viruses or reassortants thereof which causes additional challenges for diagnosis, risk assessment and disease control.
Rokshana Parvin; Jahan Ara Begum; Emadadul Haque Chowdhury; Mohammed Rafiqul Islam; Martin Beer; Timm Harder. Co-subsistence of avian influenza virus subtypes of low and high pathogenicity in Bangladesh: Challenges for diagnosis, risk assessment and control. Scientific Reports 2019, 9, 8306 .
AMA StyleRokshana Parvin, Jahan Ara Begum, Emadadul Haque Chowdhury, Mohammed Rafiqul Islam, Martin Beer, Timm Harder. Co-subsistence of avian influenza virus subtypes of low and high pathogenicity in Bangladesh: Challenges for diagnosis, risk assessment and control. Scientific Reports. 2019; 9 (1):8306.
Chicago/Turabian StyleRokshana Parvin; Jahan Ara Begum; Emadadul Haque Chowdhury; Mohammed Rafiqul Islam; Martin Beer; Timm Harder. 2019. "Co-subsistence of avian influenza virus subtypes of low and high pathogenicity in Bangladesh: Challenges for diagnosis, risk assessment and control." Scientific Reports 9, no. 1: 8306.
Influenza viruses remain an imminent threat for animal and public health. Rapid and reliable diagnosis of acute infections are at the roots of meaningful control and prevention measures. Sensitive and highly specific reverse transcription real-time PCR (RT-qPCR) assays have revolutionized the diagnostic toolbox. RT-qPCRs for subtyping and pathotype characterization of animal influenza viruses provide advantages in individual diagnosis and for long term monitoring programs.
Dinah Henritzi; Annika Graaf; Timm Harder. Spezifisch — sicher — schnell: Nachweis von Influenzaviren. BIOspektrum 2019, 25, 278 -281.
AMA StyleDinah Henritzi, Annika Graaf, Timm Harder. Spezifisch — sicher — schnell: Nachweis von Influenzaviren. BIOspektrum. 2019; 25 (3):278-281.
Chicago/Turabian StyleDinah Henritzi; Annika Graaf; Timm Harder. 2019. "Spezifisch — sicher — schnell: Nachweis von Influenzaviren." BIOspektrum 25, no. 3: 278-281.
Highly pathogenic avian influenza virus (HPAIV) infection in poultry caused devastating mortality and economic losses. HPAIV of subtypes H5 and H7 emerge from precursor viruses of low pathogenicity (LP) by spontaneous mutation associated with a shift in the susceptibility of the endoproteolytic cleavage site of the viral hemagglutinin protein from trypsin- to furin-like proteases. A recently described natural pair of LP/HP H7N7 viruses derived from two spatio-temporally linked outbreaks in layer chickens was used to study how a minority of mutated HP virions after de novo generation in a single host might gain primacy. Co-infection experiments in embryonated eggs and in chickens were conducted to investigate amplification, spread and transmissionof HPAIV within a poultry population that experiences concurrent infection by an antigenically identical LP precursor virus. Simultaneous LPAIV co-infection (inoculum dose of 106 egg-infectious dose 50% endpoint (EID50)/0.5 mL) withincreasing titers of HPAIV from 101 to 105.7 EID50/0.5 mL) had a significant impeding impact on HP H7 replication, viral excretion kinetics, clinical signs and histopathological lesions (in vivo) and on embryo mortality (in ovo). LP/HP co-infected chickens required a hundredfold higher virus dose (HPAIV inoculum of 105 EID50) compared to HPAIV mono-infection (HPAIV inoculum of 103 EID50) to develop overt clinical signs, mortality and virus spread to uninfected sentinels. Escape and spread of HP phenotypes after de novo generation in an index host may therefore be highly precarious due to significant competition with co-circulating LP precursor virus.
Annika Annika Graaf Institute of Diagnostic Virology Südufer 10 17493 Greifswald Germany; Reiner Reiner Ulrich Department of Experimental Animal Facilities and Biorisk Management Südufer 10 17493 Greifswald Germany; Pavlo Pavlo Maksimov Institute of Epidemiology Südufer 10 17493 Greifswald Germany; David David Scheibner Institute of Molecular Virology and Cell Biology Südufer 10 17493 Greifswald Germany; Susanne Koethe; Elsayed M. Abdelwhab; Thomas C. Thomas C. Mettenleiter Institute of Molecular Virology and Cell Biology Südufer 10 17493 Greifswald Germany; Martin Martin Beer Institute of Diagnostic Virology Südufer 10 17493 Greifswald Germany; Timm Harder. A viral race for primacy: co-infection of a natural pair of low and highly pathogenic H7N7 avian influenza viruses in chickens and embryonated chicken eggs. Emerging Microbes & Infections 2018, 7, 1 -12.
AMA StyleAnnika Annika Graaf Institute of Diagnostic Virology Südufer 10 17493 Greifswald Germany, Reiner Reiner Ulrich Department of Experimental Animal Facilities and Biorisk Management Südufer 10 17493 Greifswald Germany, Pavlo Pavlo Maksimov Institute of Epidemiology Südufer 10 17493 Greifswald Germany, David David Scheibner Institute of Molecular Virology and Cell Biology Südufer 10 17493 Greifswald Germany, Susanne Koethe, Elsayed M. Abdelwhab, Thomas C. Thomas C. Mettenleiter Institute of Molecular Virology and Cell Biology Südufer 10 17493 Greifswald Germany, Martin Martin Beer Institute of Diagnostic Virology Südufer 10 17493 Greifswald Germany, Timm Harder. A viral race for primacy: co-infection of a natural pair of low and highly pathogenic H7N7 avian influenza viruses in chickens and embryonated chicken eggs. Emerging Microbes & Infections. 2018; 7 (1):1-12.
Chicago/Turabian StyleAnnika Annika Graaf Institute of Diagnostic Virology Südufer 10 17493 Greifswald Germany; Reiner Reiner Ulrich Department of Experimental Animal Facilities and Biorisk Management Südufer 10 17493 Greifswald Germany; Pavlo Pavlo Maksimov Institute of Epidemiology Südufer 10 17493 Greifswald Germany; David David Scheibner Institute of Molecular Virology and Cell Biology Südufer 10 17493 Greifswald Germany; Susanne Koethe; Elsayed M. Abdelwhab; Thomas C. Thomas C. Mettenleiter Institute of Molecular Virology and Cell Biology Südufer 10 17493 Greifswald Germany; Martin Martin Beer Institute of Diagnostic Virology Südufer 10 17493 Greifswald Germany; Timm Harder. 2018. "A viral race for primacy: co-infection of a natural pair of low and highly pathogenic H7N7 avian influenza viruses in chickens and embryonated chicken eggs." Emerging Microbes & Infections 7, no. 1: 1-12.
Aquatic birds can act as vectors and reservoir hosts for pathogens relevant for wild birds and poultry as well as human health. In this study, we address the questions (1) if the Egyptian goose (Alopochen aegyptiacus), as one of the most successful neozootic bird species in Europe, carry infectious agents that are relevant for poultry and wild birds and (2) if seasonal prevalences of these infectious agents differ from those of native geese species. In 2015 and 2016, up to 190 Egyptian geese from Western Germany were investigated serologically for antibodies (Ab) against influenza A viruses (IAV), Avian avulavirus 1 (AAvV-1), aviadenoviruses, Duck atadenovirus A (syn.: egg drop syndrome 1976 virus) (EDSV), and West Nile virus (WNV). Ab were detected against IAV in 6.1% (10/164), against AAvV-1 in 2.4% (4/165), against EDSV in 15.2% (16/105), and against aviadenoviruses in 0.86% (1/116) of the geese blood samples, respectively. None of the birds had Ab against WNV (0/84). PCR-based techniques (cloacal and/or pharyngeal swabs) were applied for the presence of IAV, AAvV-1, Mycoplasma spp., and Riemerella anatipestifer. Riemerella DNA was detected in the pharyngeal swabs with an overall prevalence of 70.3% (104/148). Neither Mycoplasma DNA nor IAV or AAvV-1 RNA could be detected in the pharynx or cloaca of the examined birds. Our study shows that Egyptian geese are frequent carriers of Riemerella anatipestifer and furthermore provides serological evidence of exposure to IAV, AAvV-1, and EDSV. It is one of very few studies on infectious agents of neozootic bird species. Comparing our results from a neozootic non-migratory goose species with published results from native migratory geese species (bean goose (Anser fabalis) and white-fronted goose (A. albifrons)) and another neozootic non-migratory goose species (Canada goose (Branta canadensis)), we found differences in the seroprevalence of viral pathogens. Native goose species show higher seroprevalences of IAV and AAvV-1, whereas neozootic non-migratory geese reveal higher seroprevalences for EDSV. The findings are discussed in the frame of seasonal variations in selected infectious agents, differences in sampling periods, and contrasting movement ecology of the different geese species.
Hanna Prüter; Gábor Árpád Czirják; Sönke Twietmeyer; Timm Harder; Christian Grund; Kristin Mühldorfer; Dörte Lüschow. Sane and sound: a serologic and molecular survey for selected infectious agents in neozootic Egyptian geese (Alopochen aegyptiacus) in Germany. European Journal of Wildlife Research 2018, 64, 71 .
AMA StyleHanna Prüter, Gábor Árpád Czirják, Sönke Twietmeyer, Timm Harder, Christian Grund, Kristin Mühldorfer, Dörte Lüschow. Sane and sound: a serologic and molecular survey for selected infectious agents in neozootic Egyptian geese (Alopochen aegyptiacus) in Germany. European Journal of Wildlife Research. 2018; 64 (6):71.
Chicago/Turabian StyleHanna Prüter; Gábor Árpád Czirják; Sönke Twietmeyer; Timm Harder; Christian Grund; Kristin Mühldorfer; Dörte Lüschow. 2018. "Sane and sound: a serologic and molecular survey for selected infectious agents in neozootic Egyptian geese (Alopochen aegyptiacus) in Germany." European Journal of Wildlife Research 64, no. 6: 71.
Mahmoud M. Naguib; Timm Harder. Endemic situation of multiple avian influenza strains in poultry in Egypt: A continuing nightmare. Zoonoses and Public Health 2018, 65, 908 -910.
AMA StyleMahmoud M. Naguib, Timm Harder. Endemic situation of multiple avian influenza strains in poultry in Egypt: A continuing nightmare. Zoonoses and Public Health. 2018; 65 (8):908-910.
Chicago/Turabian StyleMahmoud M. Naguib; Timm Harder. 2018. "Endemic situation of multiple avian influenza strains in poultry in Egypt: A continuing nightmare." Zoonoses and Public Health 65, no. 8: 908-910.
Human‐ or avian‐to‐swine transmissions have founded several autonomously circulating influenza A virus (IAV) lineages in swine populations that cause economically important respiratory disease. Little is known on other human influenza virus types, like B (IBV) and C (ICV) in European swine, and of the recently detected novel animal influenza virus type D (IDV). Development of a cost‐effective diagnostic tool for large‐scale surveillance programmes targeting all four influenza virus types. An influenza ABCD tetraplex real‐time RT‐PCR (RT‐qPCR) was developed in the frame of this study. A selection of reference virus strains and more than 4000 porcine samples from a passive IAV surveillance programme in European swine with acute respiratory disease were examined. Two IBV, a single IDV but no ICV infections were identified by tetraplex RT‐qPCR. IBV and IDV results were confirmed by conventional RT‐PCR and partial sequence analysis. The tetraplex RT‐qPCR proved fit for purpose as a sensitive, specific and high‐throughput tool to study influenza virus transmission at the human‐animal interface. Complementing close‐meshed active virological and serological surveillance is required to better understand the true incidence and prevalence of influenza virus type B, C and D infections in swine.
Dinah Henritzi; Bernd Hoffmann; Silke Wacheck; Stefan Pesch; Georg Herrler; Martin Beer; Timm C. Harder. A newly developed tetraplex real‐time RT‐PCR for simultaneous screening of influenza virus types A, B, C and D. Influenza and Other Respiratory Viruses 2018, 13, 71 -82.
AMA StyleDinah Henritzi, Bernd Hoffmann, Silke Wacheck, Stefan Pesch, Georg Herrler, Martin Beer, Timm C. Harder. A newly developed tetraplex real‐time RT‐PCR for simultaneous screening of influenza virus types A, B, C and D. Influenza and Other Respiratory Viruses. 2018; 13 (1):71-82.
Chicago/Turabian StyleDinah Henritzi; Bernd Hoffmann; Silke Wacheck; Stefan Pesch; Georg Herrler; Martin Beer; Timm C. Harder. 2018. "A newly developed tetraplex real‐time RT‐PCR for simultaneous screening of influenza virus types A, B, C and D." Influenza and Other Respiratory Viruses 13, no. 1: 71-82.
In contrast to previous incursions of highly pathogenic avian influenza (HPAIV) H5 viruses, H5N8 clade 2.3.4.4b viruses caused numerous cases of lethal infections in white-tailed sea eagles (Haliaeetus albicilla) affecting mainly young eagles (younger than five years of age) in Germany during winter 2016/2017. Until April 2017, 17 HPAIV H5N8-positive white-tailed sea eagles had been detected (three found alive and 14 carcasses) by real-time RT-PCR and partial nucleotide sequence analyses. Severe neurological clinical signs were noticed which were corroborated by immunohistopathology revealing mild to moderate, oligo- to multifocal necrotizing virus-induced polioencephalitis. Lethal lead (Pb) concentrations, a main factor of mortality in sea eagles in previous years, could be ruled out by atomic absorption spectrometry. HPAIV H5 clade 2.3.4.4b reportedly is the first highly pathogenic influenza virus known to induce fatal disease in European white-tailed see eagles. This virus strain may become a new health threat to a highly protected species across its distribution range in Eurasia. Positive cloacal swabs suggest that eagles can spread the virus with their faeces.
Oliver Krone; Anja Globig; Reiner Ulrich; Timm Harder; Jan Schinköthe; Christof Herrmann; Sascha Gerst; Franz J. Conraths; Martin Beer. White-Tailed Sea Eagle (Haliaeetus albicilla) Die-Off Due to Infection with Highly Pathogenic Avian Influenza Virus, Subtype H5N8, in Germany. Viruses 2018, 10, 478 .
AMA StyleOliver Krone, Anja Globig, Reiner Ulrich, Timm Harder, Jan Schinköthe, Christof Herrmann, Sascha Gerst, Franz J. Conraths, Martin Beer. White-Tailed Sea Eagle (Haliaeetus albicilla) Die-Off Due to Infection with Highly Pathogenic Avian Influenza Virus, Subtype H5N8, in Germany. Viruses. 2018; 10 (9):478.
Chicago/Turabian StyleOliver Krone; Anja Globig; Reiner Ulrich; Timm Harder; Jan Schinköthe; Christof Herrmann; Sascha Gerst; Franz J. Conraths; Martin Beer. 2018. "White-Tailed Sea Eagle (Haliaeetus albicilla) Die-Off Due to Infection with Highly Pathogenic Avian Influenza Virus, Subtype H5N8, in Germany." Viruses 10, no. 9: 478.