Opportunistic fungal infections, such as the black fungus commonly seen in diabetics, hyperglycemia, COVID-19 patients, and linked to corticosteroids have all in common a dysregulated immune response that partly could also be attributed to IL-37 (Rammaert et al., 2012a; van Paassen et al., 2020; Kumar et al., 2021). The gene discussed is IL37; the disease is diabetes mellitus.