title: Molecular epidemiology of outbreak-associated and wild-waterfowl-derived newcastle disease virus strains in Finland, including a novel class I genotype.
abstract: Newcastle disease (ND) is a highly contagious, severe disease of poultry caused by pathogenic strains of Newcastle disease virus (NDV; or avian paramyxovirus-1). NDV is endemic in wild birds worldwide and one of the economically most important poultry pathogens. Most of the published strains are outbreak-associated strains, while the apathogenic NDV strains that occur in wild birds, posing a constant threat to poultry with their capability to convert into more virulent forms, have remained less studied. We screened for NDV RNA in cloacal and oropharyngeal samples from wild waterfowl in Finland during the years 2006 to 2010: 39 of 715 birds were positive (prevalence, 5.5%). The partial or full-length F genes of 37 strains were sequenced for phylogenetic purposes. We also characterized viruses derived from three NDV outbreaks in Finland and discuss the relationships between these outbreak-associated and the wild-bird-associated strains. We found that all waterfowl NDV isolates were lentogenic strains of class I or class II genotype I. We also isolated a genetically distinct class I strain (teal/Finland/13111/2008) grouping phylogenetically together with only strain HIECK87191, isolated in Northern Ireland in 1987. Together they seem to form a novel class I genotype genetically differing from other known NDVs by at least 12%.
authors.affiliation: Department of Virology, Haartman Institute, University of Helsinki, Helsinki, Finland. erika.lindh@helsinki.fi
authors.forename: Erika
authors.initials: E
authors.lastname: Lindh
authors.forename: Christine
authors.initials: C
authors.lastname: Ek-Kommonen
authors.forename: Veli-Matti
authors.initials: VM
authors.lastname: Väänänen
authors.forename: Jukka
authors.initials: J
authors.lastname: Alasaari
authors.forename: Antti
authors.initials: A
authors.lastname: Vaheri
authors.forename: Olli
authors.initials: O
authors.lastname: Vapalahti
authors.forename: Anita
authors.initials: A
authors.lastname: Huovilainen
mesh_terms: D000818:Animals; D001717:Birds; D002988:Cloaca / Q000821:virology; D016000:Cluster Analysis; D004196:Disease Outbreaks; D005387:Finland / Q000453:epidemiology; D005838:Genotype; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D009521:Newcastle Disease / Q000453:epidemiology* / Q000821:virology*; D009522:Newcastle disease virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D009960:Oropharynx / Q000821:virology; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D012367:RNA, Viral