title: A single dose of whole inactivated H7N9 influenza vaccine confers protection from severe disease but not infection in ferrets.
abstract: The H7N9 influenza virus caused significant mortality and morbidity in infected humans during an outbreak in China in 2013 stimulating vaccine development efforts. As previous H7-based vaccines have been poorly immunogenic in humans we sought to determine the immunogenic and protective properties of an inactivated whole virus vaccine derived from a 2013 H7N9 virus in ferrets. As whole virus vaccine preparations have been shown to be more immunogenic in humans, but less likely to be used, than split or surface antigen formulations, we vaccinated ferrets with a single dose of 15, 30, or 50 μg of the vaccine and subsequently challenged with wild-type A/Anhui/1/2013 (H7N9) either by direct instillation or by contact with infected animals. Although ferrets vaccinated with higher doses of vaccine had higher serum hemagglutinin inhibition (HI) titers, the titers were still low. During subsequent instillation challenge, however, ferrets vaccinated with 50 μg of vaccine showed no illness and shed significantly less virus than mock vaccinated controls. All vaccinated ferrets had lower virus loads in their lungs as compared to controls. In a separate study where unvaccinated-infected ferrets were placed in the same cage with vaccinated-uninfected ferrets, vaccination did not prevent infection in the contact ferrets, although they showed a trend of lower viral load. Overall, we conclude that inactivated whole-virus H7N9 vaccine was able to reduce the severity of infection and viral load, despite the lack of hemagglutinin-inhibiting antibodies.
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: Sook-San
authors.initials: SS
authors.lastname: Wong
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: Trushar
authors.initials: T
authors.lastname: Jeevan
authors.affiliation: Animal Resource Center, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Kercher
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA; Viral Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Youseong-gu, Daejeon 305-806, South Korea.
authors.forename: Sun-Woo
authors.initials: SW
authors.lastname: Yoon
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: Atanaska-Marinova
authors.initials: AM
authors.lastname: Petkova
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: Jeri-Carol
authors.initials: JC
authors.lastname: Crumpton
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: John
authors.initials: J
authors.lastname: Franks
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Debeauchamp
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: Adam
authors.initials: A
authors.lastname: Rubrum
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: Patrick
authors.initials: P
authors.lastname: Seiler
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: Scott
authors.initials: S
authors.lastname: Krauss
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Webster
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA. Electronic address: Richard.Webby@stjude.org.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Webby
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D005289:Ferrets; D006385:Hemagglutination Inhibition Tests; D064766:Influenza A Virus, H7N9 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000276:immunology*; D008168:Lung / Q000821:virology; D009976:Orthomyxoviridae Infections / Q000473:pathology* / Q000517:prevention & control*; D012720:Severity of Illness Index; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology; D019562:Viral Load; D017201:Virus Shedding
chemical_list: D000914:Antibodies, Viral; D007252:Influenza Vaccines; D015164:Vaccines, Inactivated
keywords: Ferrets; H7N9; Vaccine