In humans, preexisting IFN-γ+ CD8+ T cells lacking IL-2 production, and not IFN-γ+ IL-2+ CD8+ T cells, could be correlated with decreased symptom scores upon natural infection with pandemic H1N1 influenza virus (26), arguing against the necessity of CD8-derived IL-2 for clinical protection. The gene discussed is CD8A; the disease is infection.