Prime–boost vaccination with a fowlpox vector and an inactivated avian influenza vaccine is highly immunogenic in Pekin ducks challenged with Asian H5N1 HPAI

• Published in: Vaccine 2009-01, Vol.27 (5), p.646-654
• Main Authors: Steensels, M, Bublot, M, Van Borm, S, De Vriese, J, Lambrecht, B, Richard-Mazet, A, Chanavat-Bizzini, S, Duboeuf, M, Le Gros, F.-X, van den Berg, T
• Format: Article
• Language: English
• Subjects: Age; Allergy and Immunology; Animals; Antibodies, Viral - blood; Antigens; Applied microbiology; Aquatic birds; Asian HPAI H5N1; Biological and medical sciences; Birds; Chick Embryo; Chickens; Cloaca - virology; Ducks; Female; Fowlpox; Fowlpox virus - genetics; Fundamental and applied biological sciences. Psychology; Genes; Hemagglutination Inhibition Tests; Immune system; Immunization, Secondary; Infections; Influenza A Virus, H5N1 Subtype - genetics; Influenza A Virus, H5N1 Subtype - immunology; Influenza in Birds - immunology; Influenza in Birds - prevention & control; Influenza Vaccines - genetics; Influenza Vaccines - immunology; Microbiology; Mortality; Mouth - virology; Pekin ducks; Poultry; Vaccination; Vaccines; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies (general aspects); Vaccines, Inactivated - immunology; Vaccines, Synthetic - immunology; Virus Shedding - immunology; Wildfowl
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/j.vaccine.2008.11.044

Abstract The efficacy of different vaccination schedules was evaluated in 17-day-old Pekin ducks using an experimental inactivated whole virus vaccine based on the H5N9 A/chicken/Italy/22A/98 isolate (H5N9-It) and/or a fowlpox recombinant (vFP-H5) expressing a synthetic HA gene from an Asian H5N1 isolate (A/chicken/Indonesia/7/2003). Full protection against clinical signs and shedding was induced by the different vaccination schemes. However, the broadest antibody response and the lowest antibody increase after challenge were observed in the group of ducks whose immune system was primed with the fowlpox vectored vaccine and boosted with the inactivated vaccine, suggesting that this prime-boost strategy induced optimal immunity against H5N1 and minimal viral replication after challenge in ducks. In addition, this prime-boost vaccination scheme was shown to be immunogenic in 1-day-old ducklings.