title: H7 avian influenza virus vaccines protect chickens against challenge with antigenically diverse isolates.
abstract: Vaccination has been a critical tool in the control of some avian influenza viruses (AIV) and has been used routinely in Pakistan to help control sporadic outbreaks of highly pathogenic (HP) H7 AIV since 1995. During that time, several AIV isolates were utilized as inactivated vaccines with varying degrees of success. In order to evaluate which H7 AIV strains may serve as optimal vaccines for diverse H7 AIVs from Pakistan we conducted vaccination-challenge studies with five H7 vaccines against challenge with two HPAIVs: A/chicken/Murree/NARC-1/1995 H7N3 and A/chicken/Karachi/SPVC-4/2004 H7N3. To further characterize the isolates antigenic cartography was used to visually demonstrate the antigenic relationships among the isolates. All vaccines provided similar protection against mortality, morbidity and shedding of challenge virus from the respiratory tract. However, some minor (not statistically significant) differences were observed and correlated with antibody levels induced by the vaccine prior to challenge.
authors.affiliation: National Reference Laboratory for Poultry Diseases, NARC, Islamabad 45500, Pakistan.
authors.forename: Muhammad Athar
authors.initials: MA
authors.lastname: Abbas
authors.forename: Erica
authors.initials: E
authors.lastname: Spackman
authors.forename: Ron
authors.initials: R
authors.lastname: Fouchier
authors.forename: Derek
authors.initials: D
authors.lastname: Smith
authors.forename: Zaheer
authors.initials: Z
authors.lastname: Ahmed
authors.forename: Naila
authors.initials: N
authors.lastname: Siddique
authors.forename: Luciana
authors.initials: L
authors.lastname: Sarmento
authors.forename: Khalid
authors.initials: K
authors.lastname: Naeem
authors.forename: Enid T
authors.initials: ET
authors.lastname: McKinley
authors.forename: Abdul
authors.initials: A
authors.lastname: Hameed
authors.forename: Shafqat
authors.initials: S
authors.lastname: Rehmani
authors.forename: David E
authors.initials: DE
authors.lastname: Swayne
mesh_terms: D000818:Animals; D002645:Chickens / Q000276:immunology* / Q000821:virology; D057920:Influenza A Virus, H7N3 Subtype / Q000276:immunology* / Q000302:isolation & purification; D007252:Influenza Vaccines / Q000276:immunology*; D005585:Influenza in Birds / Q000276:immunology / Q000517:prevention & control*; D010154:Pakistan; D014611:Vaccination / Q000662:veterinary
chemical_list: D007252:Influenza Vaccines