1a.Objectives (from AD-416):
1) Pathogenesis of avian inluenza virus isolates in swine;. 2)Role of avian polymerases in adaptation of swine influenza viruses to swine;. 3)Genetic characterization of swine and avian influenza viruses to swine; and. 4)Preparation of reagents.
1b.Approach (from AD-416):
1) Pathogenesis of avian influenza virus isolates in swine will be evaluated after inoculation into a group of four week old pigs. Microscopic and macroscopic lung lesions and viral replication in lungs and nasal cavities will be determined.. 2)Various reassortant viruses containing avian and/or swine polymerase genes will be established using reverse genetics approaches. These reassortant viruses will be tested for their pathogenic potential in swine.. 3)Swine and avian influenza isolates will be genetically characterized using conventional sequencing approaches.. 4)Hyperimmune sera and various viruses will be made available as reagents.
A study was completed testing the susceptibility of young pigs to infection with an isolate of H7N9 influenza A virus from the 2012 Chinese human epidemic. Although pigs could be infected following intranasal inoculation, only minimal disease was recognized. Based on this initial study, pig-to-pig transmission of the H7N9 virus is unlikely indicating swine may not be origin of the H7N9 virus. This data supports current reports that the H7N9 virus was transmitted from birds to people.