Preventing Respiratory Syncytial Virus in Infants: A Comparative Review of Nirsevimab and Maternal Respiratory Syncytial Virus Prefusion F (RSVpreF) Vaccination.

Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract disease in early infancy. Preventive options have recently expanded beyond selective palivizumab use to two population-level strategies: infant administration of the long-acting monoclonal antibody nirsevimab and maternal immunization with an RSV prefusion F (RSVpreF) vaccine during late pregnancy. This review synthesizes current evidence on the efficacy, safety, durability, and programmatic considerations of both approaches, with attention to comparative strengths and real-world implementation. We outline clinical trial findings, early post-licensure effectiveness and safety data, and health-economic considerations relevant to diverse health systems. We also discuss limitations of the evidence base and propose priorities for surveillance and comparative research to guide policy decisions. The goal is to provide clinicians and policymakers with a concise, practice-oriented appraisal of how these strategies can be integrated to reduce RSV burden in the first months of life.