Lactoferrin (LF) is a major serum protein present in mammalian milk, particularly abundant in colostrum and to a less extent in mature milk. It has antimicrobial effects in the premature and full-term newborn when supplemented either in terms of efficacy (less incidence of late sepsis, less necrotizing enterocolitis), and also of safety profile. The real challenge concerns the potential effects of LF on prevention of viral infections in infants and children, including prevention of flu or even Coronavirus infections. In vitro studies have shown that LF is able to prevent viral infection with an effect that is dose-dependent, precisely by acting through the interaction with heparin sulfate glycosaminoglycan cell receptors (HSPGs). At the level of cell surface, LF effectively prevents the initial viral anchoring and accumulation which are the initial part of viral infection that continues then with the entry into the cell. Further studies that give clinical strength to these evidences are needed. In the meantime, please consider the power of mother’s milk.