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  • 151.
    Wille, Michelle
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Uppsala University.
    Latorre-Margalef, Neus
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. University of Georgia, USA.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Stallknecht, D. E.
    University of Georgia, USA.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    No evidence for homosubtypic immunity of influenza H3 in Mallards following vaccination in a natural experimental system2017In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 26, no 5, p. 1420-1431Article in journal (Refereed)
    Abstract [en]

    The Mallard (Anas platyrhynchos) is an important reservoir species for influenza A viruses (IAV), and in this host, prevalence and virus diversity are high. Studies have demonstrated the presence of homosubtypic immunity, where individuals are unlikely to be reinfected with the same subtype within an autumn season. Further, evidence for heterosubtypic immunity exists, whereby immune responses specific for one subtype offer partial or complete protection against related HA subtypes. We utilized a natural experimental system to determine whether homo- or heterospecific immunity could be induced following experimental vaccination. Thirty Mallards were vaccinated with an inactivated H3, H6 or a sham vaccine and after seroconversion were exposed to naturally infected wild conspecifics. All ducks were infected within 2days and had both primary and secondary infections. Overall, there was no observable difference between groups; all individuals were infected with H3 and H10 IAV. At the cessation of the experiment, most individuals had anti-NP antibodies and neutralizing antibodies against H10. Not all individuals had H3 neutralizing antibodies. The isolated H3 IAVs revealed genetic dissimilarity to the H3 vaccine strain, specifically substitutions in the vicinity of the receptor-binding site. There was no evidence of vaccine-induced homosubtypic immunity to H3, a likely result of both a poor H3 immune response in the ducks and H3 immune escape. Likewise, there was no observed heterosubtypic protection related to H6 vaccination. This study highlights the need for experimental approaches to assess how exposure to pathogens and resulting immune processes translates to individual and population disease dynamics.

  • 152.
    Wille, Michelle
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Latorre-Margalef, Neus
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Stallknecht, D.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Putative escape and poor humoral response to inactivatedvaccine in Mallards results in no homo- or heterosubtypic immunity againstH3 influenza A in a natural-experimental system.Manuscript (preprint) (Other academic)
  • 153.
    Wille, Michelle
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Avril, Alexis
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. CIRAD, Campusinternational de Baillarguet, Montpellier 34398, France.
    Latorre-Margalef, Neus
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Wallerström, Sofie
    Karolinska institutet.
    Olsen, Björn
    Uppsala universitet.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Frequency and patterns of reassortment in natural influenza A virus infection in a reservoir host2013In: Virology, ISSN 0042-6822, E-ISSN 1096-0341, Vol. 443, no 15, p. 150-160Article in journal (Refereed)
    Abstract [en]

    Influenza A viruses (IAV) can dramatically alter both genotype and phenotype at a rapid rate as a product of co-infection and reassortment Avian IAV exhibit high levels of phylogenetic incongruence, suggesting high levels of reassortment in the virus reservoir. Using a natural-experimental system, we reconstructed relationships amongst 92 viruses across 15 subtypes from 10 Mallards in an autumn season. Phylogenetic analyses estimated that 56% of the isolated viruses were reassorted. Network analysis demonstrated different patterns of reassortment and limited exchange of segments between primary and secondary infections. No clear patterns of linkage between segments were found, and patterns within a season were likely the consequence of continued introduction ofnew constellations, high viral load and diversity in the wild bird reservoir, and co-infections. This is the first IAV study to implement multiple tools available for elucidating factors governing reassortment patterns in naturally infected Mallards.

  • 154.
    Wille, Michelle
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Latorre-Margalef, Neus
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Fouchier, R. A. M.
    Halpin, R. A.
    Wentworth, D. E.
    Ragwani, J.
    Pybus, O.
    Olsen, Björn
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Limited diffusion of genome constellations and pervasive reassortment arefeatures of long-term circulation of H4N6 influenza A in European waterfowlManuscript (preprint) (Other academic)
  • 155.
    Wille, Michelle
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    van Run, Peter
    Erasmus Medical Centre, The Netherlands.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Kuiken, Thijs
    Erasmus Medical Centre, The Netherlands.
    Infected or not: are PCR-positive oropharyngeal swabs indicative of low pathogenic influenza A virus infection in the respiratory tract of Mallard Anas platyrhynchos?2014In: Veterinary research (Print), ISSN 0928-4249, E-ISSN 1297-9716, Vol. 45, p. Article ID: 53-Article in journal (Refereed)
    Abstract [en]

    Detection of influenza virus in oropharyngeal swabs collected during wild bird surveillance is assumed to representrespiratory infection, although intestine is the main site of infection. We tested this assumption by histologicalexamination of the respiratory tract of wild Mallards with virus-positive oropharyngeal swabs. Thirty-two of 125Mallards tested had viral-RNA positive oropharyngeal swabs. The respiratory tracts of four Mallards with the mostvirus were examined in detail by immunohistochemistry. None had detectable virus antigen in the respiratory tract,suggesting it was not infected. An alternative explanation is that the oropharynx was contaminated with virusthrough feeding in surface water or through preening.

  • 156.
    Williams, Richard A. J.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tolf, Conny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Molecular identification of papillomavirus in ducks2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 9096Article in journal (Refereed)
    Abstract [en]

    Papillomaviruses infect many vertebrates, including birds. Persistent infections by some strains can cause malignant proliferation of cells (i.e. cancer), though more typically infections cause benign tumours, or may be completely subclinical. Sometimes extensive, persistent tumours are recorded-notably in chaffinches and humans. In 2016, a novel papillomavirus genotype was characterized from a duck faecal microbiome, in Bhopal, India; the sixth papillomavirus genotype from birds. Prompted by this finding, we screened 160 cloacal swabs and 968 faecal samples collected from 299 ducks sampled at Ottenby Bird Observatory, Sweden in 2015, using a newly designed real-time PCR. Twenty one samples (1.9%) from six individuals (2%) were positive. Eighteen sequences were identical to the published genotype, duck papillomavirus 1. One additional novel genotype was recovered from three samples. Both genotypes were recovered from a wild strain domestic mallard that was infected for more than 60 days with each genotype. All positive individuals were adult (P = 0.004). Significantly more positive samples were detected from swabs than faecal samples (P < 0.0001). Sample type data suggests transmission may be via direct contact, and only infrequently, via the oral-faecal route. Infection in only adult birds supports the hypothesis that this virus is sexually transmitted, though more work is required to verify this.

  • 157. Yohannes, E.
    et al.
    Hansson, B.
    Lee, R.W.
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Åkesson, M.
    Hasselquist, D.
    Bensch, S
    Isotope signatures in winter moulted feathers predict malaria prevalence in a breeding avian host2008In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 158, no 2, p. 299-306Article in journal (Refereed)
    Abstract [en]

    It is widely accepted that animal distribution and migration strategy might have co-evolved in relation to selection pressures exerted by parasites. Here, we first determined the prevalence and types of malaria blood parasites in a breeding population of great reed warblers Acrocephalus arundinaceus using PCR. Secondly, we tested for differences in individual feather stable isotope signatures (δ 13C, δ 15N, δD and δ 34S) to investigate whether malaria infected and non-infected birds had occupied different areas in winter. We show that birds moulting in Afro-tropical habitats with significantly higher δ 13C and δ 15N but lower δD and δ34S values were more frequently infected with malaria parasites. Based on established patterns of isotopic distributions, our results indicate that moulting sites with higher incidence of malaria are generally drier and situated further to the north in West Africa than sites with lower incidence of malaria. Our findings are pertinent to the general hypothesis that animal distribution and particularly avian migration strategy might evolve in response to selection pressures exerted by parasites at different geographic scales. Tradeoffs between investment in energy demanding life history traits (e.g. migration and winter moult) and immune function are suggested to contribute to the particular choice of habitat during migration and at wintering sites.

  • 158. Zohari, Siamak
    et al.
    Gyarmati, P.
    Ejdersund, A.
    Berglöf, U.
    Thorén, P.
    Ehrenberg, M.
    Czifra, G.
    Belak, S.
    Waldenström, Jonas
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Olsen, Björn
    University of Kalmar, School of Pure and Applied Natural Sciences.
    Berg, M.
    Phylogenetic analysis of the non-structural (NS) gene of influenza A viruses isolated from mallards in Northern Europe in 20052008In: Virology Journal, ISSN 1743-422X, E-ISSN 1743-422X, Vol. 5, no Article ID: 147Article in journal (Refereed)
    Abstract [en]

    Background: Although the important role of the non-structural 1 (NS) gene of influenza A in virulence of the virus is well established, our knowledge about the extent of variation in the NS gene pool of influenza A viruses in their natural reservoirs in Europe is incomplete. In this study we determined the subtypes and prevalence of influenza A viruses present in mallards in Northern Europe and further analysed the NS gene of these isolates in order to obtain a more detailed knowledge about the genetic variation of NS gene of influenza A virus in their natural hosts. Results: A total number of 45 influenza A viruses of different subtypes were studied. Eleven haemagglutinin-and nine neuraminidase subtypes in twelve combinations were found among the isolated viruses. Each NS gene reported here consisted of 890 nucleotides; there were no deletions or insertions. Phylogenetic analysis clearly shows that two distinct gene pools, corresponding to both NS allele A and B, were present at the same time in the same geographic location in the mallard populations in Northern Europe. A comparison of nucleotide sequences of isolated viruses revealed a substantial number of silent mutations, which results in high degree of homology in amino acid sequences. The degree of variation within the alleles is very low. In our study allele A viruses displays a maximum of 5% amino acid divergence while allele B viruses display only 2% amino acid divergence. All the viruses isolated from mallards in Northern Europe possessed the typical avian ESEV amino acid sequence at the C-terminal end of the NSI protein. Conclusion: Our finding indicates the existence of a large reservoir of different influenza A viruses in mallards population in Northern Europe. Although our phylogenetic analysis clearly shows that two distinct gene pools, corresponding to both NS allele A and B, were present in the mallards populations in Northern Europe, allele B viruses appear to be less common in natural host species than allele A, comprising only about 13% of the isolates sequenced in this study.

1234 151 - 158 of 158
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