Maternal Respiratory Syncytial Virus Prefusion F Vaccination and Acute Respiratory Illness in Infants

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RSV is the leading cause of lower respiratory tract disease in infants, causing 33 million cases and 100,000 deaths annually worldwide.
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The FDA approved the RSVpreF vaccine in August 2023 to prevent RSV-associated LRTD in infants through maternal immunization.
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The pivotal phase 3 trial showed RSVpreF efficacy of 57.6% against RSV-associated medically attended LRTD in infants aged 0 to 90 days.
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The CASSATT study evaluates the effectiveness of maternal RSVpreF vaccination against hospitalization for RSV-associated acute respiratory illness in infants.
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Infants born to vaccinated individuals were classified as exposed, while those without vaccination were classified as unexposed for the study.

Jama Network Open

by Anne-Marie Rick, Jennifer Deese, Jessica E. Kerr, Jonathan Hui, Hui Liu, Guan Yu, Chung-Chou H. Chang, Nicole Fazio, Muhammad H. Tahir, Rachael Bieltz, Anjani Ravindra, Christina Megli, Arun Jeyabalan, Sarah J. Pugh, Divya Patel, Rong Fan, Jessica E. Atwell, Alejandro Cané, Judith M. Martin
June 5, 2026

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