Respiratory Syncytial Virus Infection—The Key to Prevent Infantile Disease

Respiratory syncytial virus (RSV) causes a spectrum of respiratory diseases in infants and young children that can lead to hospitalizations and many outpatient visits, resulting in a huge public health and economic burden. Most hospitalizations occur in otherwise healthy infants, highlighting the need to protect all infants against RSV. Moreover, there is evidence of an association between RSV respiratory disease in early life and recurrent asthma-like wheezing symptoms. Therefore, RSV is considered a global health priority. However, the only prevention strategy currently available is a monoclonal antibody (mAb) indicated in former preterm infants or those with severe comorbidities, thus leaving the majority of the infant population unprotected against this virus. Therefore, the development of RSV prevention strategies for all infants entering their first RSV season represents a large unmet medical need. Current prevention strategies include maternal immunization, infant immunization with vaccines, and infant immunization with licensed monoclonal antibodies.The use of mAb is limited to a small population of infants and does not provide a solution for the protection of all children, while vaccine development in infants has faced various challenges, including the immaturity of the infant immune system, highlighting that future pediatric vaccines will be the most probably used in older infants (>6 months) and children. Maternal immunization and infant immunization with long-acting monoclonal antibodies are two feasible strategies to protect all children against RSV. Based on current data, immunization of infants with long-acting monoclonal antibodies may represent the most effective approach to protect all children entering their first RSV season.