CEIRR will determine the molecular, ecologic and/or environmental factors that influence the evolution, emergence, transmission and pathogenicity of influenza viruses, and characterize the immune response to influenza infection to improve understanding of the immune correlates of protection and cross-protection. CEIRR will carry out a host of activities, including cohort studies and human and animal sampling to further understanding of influenza infection, transmission and vaccination; identification of immunological factors that determine disease outcome in the response to influenza infection and vaccination; and studies to determine how influenza viruses evolve, adapt and transmit between humans and at interspecies interfaces.