Journal of pediatrics. Clinical practice
Uptake of Respiratory Syncytial Virus Prefusion F Protein Vaccination during Pregnancy and nirsevimab among Infants over Two Seasons in a Single Health System
By Kerr JE, Calzadilla AJ, Liu H and 1 others.
Abstract
Objective
To describe the uptake of respiratory syncytial virus (RSV) prevention products during the first 2 seasons after availability in the US in a large health system.
Study design
Using multisource immunization data from a single health system, we identified a retrospective cohort of infants born from October 2023 to April 2024 (season 1) and from September 2024 to April 2025 (season 2) and their birth parents. We described the uptake of RSV prefusion F protein (RSVpreF) vaccination and nirsevimab and evaluated factors associated with receipt using multivariable logistic regression.
Results
Among 10 196 infants, 5868/10 196 (57.6%) were exposed to an RSV-preventive product. Overall, in our maternal-infant dyads, 3850/10 196 (37.8% of total) received RSVpreF, 1837/10 196 infants (18.0% of total) received nirsevimab, and in 181/10 196 (1.8%), both were received. Uptake increased from 2100/4555 (46.1%) in season 1 to 3768/5641 (66.8%) in season 2 (P < .001). Maternal RSVpreF vaccination increased from 1280/4555 (28.1%) to 2570/5641 (45.6%), and nirsevimab uptake increased from 749/4555 (16.4%) to 1088/5641 (19.3% both P < .001). Nirsevimab receipt at <6 days of life increased from 242/749 (32.2%) to 502/1088 (46.1%, P < .001). RSVpreF uptake was higher among older, privately insured pregnant individuals and those engaged in other preventative care and lower among those with higher area deprivation, more complex obstetric histories, or other children. Nirsevimab uptake was higher among infants with prematurity or from multifetal births and lower among those with siblings, later-season birth, or no early outpatient care. Social and structural disparities in nirsevimab uptake improved in the second season, whereas disparities in RSVpreF uptake persisted.