title: Spillback transmission of European H1N1 avian-like swine influenza viruses to turkeys: A strain-dependent possibility?
abstract: In 1979, an avian influenza virus of the H1N1 subtype began to circulate in European swine herds, rapidly replacing classical swine H1N1 viruses. Spill-back transmissions to turkeys were recorded occasionally, but they might have been underreported due to the asymptomatic nature of the infection and the lack of specific surveillance. In our study, we evaluated the infectivity and transmissibility in turkeys of seven strains of H1N1 avian-like swine viruses isolated from 1979 to 2006, and compared them with their closest progenitor A/duck/Bavaria/1/77 (H1N1), to establish whether the adaptation to pigs has gradually decreased their fitness in turkeys. Our data indicate that the circulation of European H1N1 in pigs might have impaired the possibility of infecting turkeys. Nevertheless, the two swine-origin strains, which showed the ability to replicate and transmit in turkeys, possess typical swine-like genetic traits, not different from the rest of the tested isolates, suggesting replication of avian-like swine H1N1 viruses in turkeys as a strain-dependent polygenic feature.
authors.affiliation: Istituto Zooprofilattico Sperimentale delle Venezie, Department of Comparative Biomedical Sciences, OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, OIE Collaborating Centre for Diseases at the Human-Animal Interface, Viale dell'Università 10, 35020 Legnaro, Padova, Italy. Electronic address: fbonfante@izsvenezie.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Bonfante
authors.affiliation: Istituto Zooprofilattico Sperimentale delle Venezie, Department of Comparative Biomedical Sciences, OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, OIE Collaborating Centre for Diseases at the Human-Animal Interface, Viale dell'Università 10, 35020 Legnaro, Padova, Italy. Electronic address: afusaro@izsvenezie.it.
authors.forename: Alice
authors.initials: A
authors.lastname: Fusaro
authors.affiliation: Istituto Zooprofilattico Sperimentale delle Venezie, Department of Comparative Biomedical Sciences, OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, OIE Collaborating Centre for Diseases at the Human-Animal Interface, Viale dell'Università 10, 35020 Legnaro, Padova, Italy. Electronic address: ltassoni@izsvenezie.it.
authors.forename: Luca
authors.initials: L
authors.lastname: Tassoni
authors.affiliation: Istituto Zooprofilattico Sperimentale delle Venezie, Department of Comparative Biomedical Sciences, OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, OIE Collaborating Centre for Diseases at the Human-Animal Interface, Viale dell'Università 10, 35020 Legnaro, Padova, Italy. Electronic address: liviavictoria.patrono@gmail.com.
authors.forename: Livia Victoria
authors.initials: LV
authors.lastname: Patrono
authors.affiliation: Istituto Zooprofilattico Sperimentale delle Venezie, Department of Comparative Biomedical Sciences, OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, OIE Collaborating Centre for Diseases at the Human-Animal Interface, Viale dell'Università 10, 35020 Legnaro, Padova, Italy. Electronic address: amilani@izsvenezie.it.
authors.forename: Adelaide
authors.initials: A
authors.lastname: Milani
authors.affiliation: Istituto Zooprofilattico Sperimentale delle Venezie, Department of Comparative Biomedical Sciences, OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, OIE Collaborating Centre for Diseases at the Human-Animal Interface, Viale dell'Università 10, 35020 Legnaro, Padova, Italy. Electronic address: smaniero@izsvenezie.it.
authors.forename: Silvia
authors.initials: S
authors.lastname: Maniero
authors.affiliation: Istituto Zooprofilattico Sperimentale delle Venezie, Department of Comparative Biomedical Sciences, OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, OIE Collaborating Centre for Diseases at the Human-Animal Interface, Viale dell'Università 10, 35020 Legnaro, Padova, Italy. Electronic address: asalviato@izsvenezie.it.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Salviato
authors.affiliation: Istituto Zooprofilattico Sperimentale delle Venezie, Department of Comparative Biomedical Sciences, OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, OIE Collaborating Centre for Diseases at the Human-Animal Interface, Viale dell'Università 10, 35020 Legnaro, Padova, Italy. Electronic address: cterregino@izsvenezie.it.
authors.forename: Calogero
authors.initials: C
authors.lastname: Terregino
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D004912:Erythrocytes / Q000821:virology; D006388:Hemagglutinins / Q000737:chemistry; D058507:Host Specificity; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000145:classification* / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification; D005585:Influenza in Birds / Q000276:immunology / Q000635:transmission* / Q000821:virology*; D050296:Microbial Viability; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D017385:Sequence Homology; D013552:Swine; D013553:Swine Diseases / Q000821:virology; D014422:Turkeys; D053585:Virus Attachment; D014779:Virus Replication / Q000502:physiology; D017201:Virus Shedding
chemical_list: D000914:Antibodies, Viral; D006388:Hemagglutinins
keywords: Receptor binding specificity; Swine influenza; Transmissibility; Turkeys