Treatment of mice with an FDA-approved TNFα inhibitor increased survival but prolonged and exacerbated lung pathology, raising concerns for the risk of severe influenza in patients prescribed TNFα-blocking drugs commonly used to treat rheumatoid arthritis, irritable bowel syndrome, and psoriasis (Shale et al., 2010; Damjanovic et al., 2011; Shi et al., 2013). Here, TNF is linked to influenza.