Influenza virus is primarily transmitted via inhaled aerosols and results in an infection localized to the upper respiratory tract, with viral replication largely limited to epithelial cells [3] . Mechanisms by which the immune system eliminates influenza have been well studied and are known to involve the coordinated actions of the innate and adaptive immune systems. Namely, the cytolytic action of influenza-specific CD8 T cells has been shown to be the primary mediator of complete viral clearance, but important roles have also been described for CD4 T cells [4, 5, 6] . In addition to T cells, a crucial role has also been established for innate immune effectors including natural killer (NK) cells, which provide short-term control of viral replication prior to T cell activation [7] . NK cells become activated following the loss of inhibitory signals coupled with positive activating signals resulting in direct (via release of cytotoxic granules and interferon c) or indirect (via activation of macrophages and dendritic cells) target cell lysis [8] . NK cells are vital in limiting influenza viral replication as depletion of NK cells dramatically increases morbidity and mortality in hamsters and mice [9] , and in humans severe infections with the 2009 pandemic H1N1 virus positively correlated with reduced numbers of NK cells in the lungs [10] . Studies have indicated that the natural cytotoxicity receptors NKp44 and NKp46, which recognize hemagglutinin proteins of several different influenza strains [11, 12] is one mechanism used by NK cells to protect against lethal viral challenge [13] . Secondarily, NK cells also aid in viral clearance indirectly through the production and secretion of cytokines which both amplifies local inflammation and recruits antigen-specific CD8 T cells to sites of inflammation [14] . Implicit in both of these functions is the ability of NK cells to accumulate within the respiratory tract to contact infected cells and provide a source of chemotactic signals to recruit recently activated CD8 T cells.