title: Cross-protection against H7N9 influenza strains using a live-attenuated H7N3 virus vaccine.
abstract: In 2013, avian H7N9 influenza viruses were detected infecting people in China resulting in high mortality. Influenza H7 vaccines that provide cross-protection against these new viruses are needed until specific H7N9 vaccines are ready to market. In this study, an available H7N3 cold-adapted, temperature sensitive, live attenuated influenza vaccine (LAIV) elicited protective immune responses in ferrets against H7N9 viruses. The H7N3 LAIV administered alone (by intranasal or subcutaneous administration) or in a prime-boost strategy using inactivated H7N9 virus resulted in high HAI titers and protected 100% of the animals against H7N9 challenge. Naïve ferrets passively administered immune serum from H7N3 LAIV infected animals were also protected. In contrast, recombinant HA protein or inactivated viruses did not protect ferrets against challenge and elicited lower antibody titers. Thus, the H7N3 LAIV vaccine was immunogenic in healthy seronegative ferrets and protected these ferrets against the newly emerged H7N9 avian influenza virus.
authors.affiliation: Vaccine and Gene Therapy Institute of Florida, Port St. Lucie, FL, USA.
authors.forename: Donald M
authors.initials: DM
authors.lastname: Carter
authors.affiliation: Vaccine and Gene Therapy Institute of Florida, Port St. Lucie, FL, USA.
authors.forename: Chalise E
authors.initials: CE
authors.lastname: Bloom
authors.affiliation: Vaccine and Gene Therapy Institute of Florida, Port St. Lucie, FL, USA.
authors.forename: Greg A
authors.initials: GA
authors.lastname: Kirchenbaum
authors.affiliation: PATH, Washington, DC, USA.
authors.forename: Vadim
authors.initials: V
authors.lastname: Tsvetnitsky
authors.affiliation: Department of Virology, Institute of Experimental Medicine, Saint Petersburg, Russia.
authors.forename: Irina
authors.initials: I
authors.lastname: Isakova-Sivak
authors.affiliation: Department of Virology, Institute of Experimental Medicine, Saint Petersburg, Russia.
authors.forename: Larisa
authors.initials: L
authors.lastname: Rudenko
authors.affiliation: Vaccine and Gene Therapy Institute of Florida, Port St. Lucie, FL, USA. Electronic address: tross@vgtifl.org.
authors.forename: Ted M
authors.initials: TM
authors.lastname: Ross
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002681:China; D056738:Cross Protection; D005289:Ferrets; D057920:Influenza A Virus, H7N3 Subtype / Q000276:immunology*; D064766:Influenza A Virus, H7N9 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000276:immunology*; D007279:Injections, Subcutaneous; D008297:Male; D009976:Orthomyxoviridae Infections / Q000517:prevention & control; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D007252:Influenza Vaccines; D015164:Vaccines, Inactivated
keywords: Antibodies; Ferrets; H7N9; Influenza; Live-attenuated