LID scientists are collaborating with scientists from MedImmune under a CRADA to generate candidate vaccines against pandemic influenza viruses, including the 2009 pandemic H1N1 virus. The vaccine was generated using plasmid based reverse genetics and contains the hemagglutinin and neuraminidase genes from the pandemic H1N1 influenza virus and six internal gene segments from the AA ca virus. The immunogenicity and efficacy of the vaccine will be evaluated in animal models. The serum antibody response to one or two doses of vaccine will be evaluated using hemagglutination inhibition and neutralizing antibody assays and the efficacy will be evaluated by challenging vaccinated animals with the wild-type H1N1 pandemic influenza virus.