In the study by Sposito et al, IFN-λ1 was the more potent ISGs inducer with respect to λ2 and - λ3 and to type I IFNs in mild COVID-19 adults’ patients; IFN-λ1 potency could be a reason to keep its basal expression and its activation low upon infections. This evidence concerns the gene IFNL1 and infection.