title: Age at Vaccination and Timing of Infection Do Not Alter Vaccine-Associated Enhanced Respiratory Disease in Influenza A Virus-Infected Pigs.
abstract: Whole inactivated virus (WIV) vaccines are widely used in the swine industry to reduce clinical disease against homologous influenza A virus (IAV) infection. In pigs experimentally challenged with antigenically distinct heterologous IAV of the same hemagglutinin subtype, WIV vaccinates have been shown to develop vaccine-associated enhanced respiratory disease (VAERD). We evaluated the impact of vaccine valency, age at vaccination, and duration between vaccination and challenge on the development of VAERD using vaccine containing δ1-H1N2 and challenge with pandemic H1N1 (pH1N1) virus. Pigs were vaccinated with monovalent WIV MN08 (δ1-H1N2) and bivalent (δ1-H1N2-H3N2 or δ1-H1N2-pH1N1) vaccines and then were challenged with pH1N1 at 3 weeks postboost (wpb). Another group was vaccinated with the same monovalent WIV and challenged at 6 wpb to determine if the time postvaccination plays a role in the development of VAERD. In a follow-up study, the impact of age of first WIV vaccination (at 4 versus 9 weeks of age) with a boost 3 weeks later (at 7 versus 12 weeks of age) was evaluated. A monovalent live-attenuated influenza virus (LAIV) vaccine administered at 4 and 7 weeks of age was also included. All mismatched WIV groups had significantly higher lung lesions than the LAIV, bivalent MN08-CA09, and control groups. Age of first vaccination or length of time between booster dose and subsequent challenge did not alter the development of VAERD in WIV-vaccinated pigs. Importantly, the mismatched component of the bivalent MN08-CA09 WIV did not override the protective effect of the matched vaccine component.
authors.affiliation: Virus and Prion Diseases Research Unit, USDA-ARS, Ames, Iowa, USA.|Laboratório de Virologia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Carine K
authors.initials: CK
authors.lastname: Souza
authors.affiliation: Virus and Prion Diseases Research Unit, USDA-ARS, Ames, Iowa, USA.
authors.forename: Daniela S
authors.initials: DS
authors.lastname: Rajão
authors.affiliation: Virus and Prion Diseases Research Unit, USDA-ARS, Ames, Iowa, USA.
authors.forename: Crystal L
authors.initials: CL
authors.lastname: Loving
authors.affiliation: Iowa State University (ISU), Ames, Iowa, USA.
authors.forename: Phillip C
authors.initials: PC
authors.lastname: Gauger
authors.affiliation: Poultry Diagnostic and Research Center, University of Georgia, Athens, Georgia, USA.
authors.forename: Daniel R
authors.identifier: http://orcid.org/0000-0002-6569-5689
authors.initials: DR
authors.lastname: Pérez
authors.affiliation: Virus and Prion Diseases Research Unit, USDA-ARS, Ames, Iowa, USA amy.vincent@ars.usda.gov.
authors.forename: Amy L
authors.initials: AL
authors.lastname: Vincent
mesh_terms: D000367:Age Factors; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D005500:Follow-Up Studies; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology* / Q000302:isolation & purification / Q000502:physiology; D053122:Influenza A Virus, H3N2 Subtype / Q000276:immunology* / Q000302:isolation & purification / Q000502:physiology; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*; D008168:Lung / Q000473:pathology / Q000821:virology; D009976:Orthomyxoviridae Infections / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D012140:Respiratory Tract Diseases / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary* / Q000821:virology; D013552:Swine; D013553:Swine Diseases / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D013997:Time Factors; D014611:Vaccination / Q000009:adverse effects; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000276:immunology; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D007252:Influenza Vaccines; D014613:Vaccines, Attenuated; D015164:Vaccines, Inactivated