Additional mutations associated with severe influenza (reviewed in [1, 4]) have been described in the complement factor CD55/DAF [18], the pulmonary surfactant protein SFTPA2 [19], the protease TMPRSS2 [20], the endothelial transcriptional activator GATA2 [21], interferon regulators IRF7 and IRF9 [22–24], and the endosomal dsRNA receptor TLR3 [25–27]. This evidence concerns the gene CD55 and influenza.