Neither IFI44 nor NDUFAF4 have already been associated with persistent OD; however, considering literature data, it may be hypothesized that individuals with a higher accumulation of biallelic variants in both genes may present more efficient viral clearance during the acute phase of COVID-19 and therefore develop a decreased inflammatory response in the OE that thus correlates with a better outcome in olfactory performance. The gene discussed is NDUFAF4; the disease is COVID-19.