Our results are consistent with these findings in that, in general, there is a poor GrB response to vaccination against influenza A/H3N2 and B and thus influenza vaccination is unlikely to affect the balance between GrB+Perf+ CD8+ T cells and GrB+Perf− CD8+ T cells responding to influenza infection and risk for influenza illness. The gene discussed is FABP9; the disease is influenza.