There was no association between protection against pneumonia or death and the presence of polyfunctional CD8+ T-cells, both at influenza diagnosis (38.9% [7/18] vs 38.5% [5/13]; p = 0.638) or at Day 28 (44.4% [8/18] vs 38.5% [5/13]; p = 0.516). This evidence concerns the gene CD8A and susceptibility to pneumonia measurement.