US Infant RSV Hospitalizations Fall 71% After New Vaccine, Treatment

The 2024–2025 RSV season saw a significant decline in hospitalizations of infants struggling with respiratory syncytial virus, attributed to the introduction of two new preventive measures approved in the U.S.: Pfizer's maternal vaccine Abrysvo and the monoclonal antibody treatment nirsevimab (Beyfortus). The maternal vaccine is administered during the third trimester of pregnancy, passing antibodies to the fetus to protect newborns, while the antibody treatment is given to babies under eight months old entering their first RSV season. CDC data indicate that this combination likely contributed to the drop in severe RSV cases among the most vulnerable infants, although hospitalizations rose in older children not eligible for these interventions. Concurrently, the U.S. infant mortality rate fell slightly in 2024, from 5.6 to 5.5 deaths per 1,000 live births, marking a reversal of the previous two years' increase linked to RSV and flu rebounds after pandemic precautions eased. Experts suggest that the rollout of RSV vaccinations and antibody treatments played a role in improving infant survival alongside other ongoing public health efforts. These advances offer hope for reducing RSV's serious impact on infants and their families in the coming years.