Real-World Data Confirms Maternal RSV Vaccine Delivers 70% Drop in Infant Hospitalizations, Reshaping Pediatric Policy

The University of Pittsburgh-led observational study in JAMA Network Open provides compelling early evidence that maternal RSVpreF vaccination reduces RSV-related infant hospitalizations by 68-69% in the first 90 days of life. Unlike the pivotal MATISSE randomized controlled trial (NEJM 2023, n=7,392 pregnancies), this analysis draws from real-world U.S. clinical records across two RSV seasons in western Pennsylvania, excluding infants who received nirsevimab. While observational designs carry risks of confounding and smaller effective sample sizes than RCTs, the consistency with trial efficacy data strengthens causal inference. No industry conflicts were disclosed by the Pitt/UPMC team. This 70% effectiveness metric represents a measurable public-health win, directly lowering demand for pediatric ICU beds and oxygen support during peak winter months. It also highlights gaps missed by initial coverage: protection duration beyond 90 days remains unproven here, and uptake disparities across socioeconomic groups could blunt population-level impact. CDC surveillance data (2024) showing 2-3 hospitalizations per 100 infants under 3 months underscores the stakes. Ongoing four-season follow-up will clarify waning immunity and inform ACIP recommendations.