Effectiveness of catch-up and at-birth nirsevimab immunisation against RSV hospital admission in the first year of life: a population-based case-control study, Spain, 2023/24 season.

ABSTRACT: BackgroundRespiratory syncytial virus (RSV) causes substantial morbidity in infants < 1 year. In October 2023, Spain recommended the monoclonal antibody nirsevimab to all children born since 1 April 2023, at birth or as catch-up if born before October 2023.AimWe estimated nirsevimab effectiveness in preventing RSV hospitalisations during the 2023/24 season.MethodsWe conducted a nationwide population-based matched case-control study. Cases were children hospitalised for lower respiratory tract infection who were RSV PCR-positive. For each case, we selected four population density controls born in the same province and date (±2 days). We defined at-birth immunisation as receiving nirsevimab during the first 2 weeks of life, and catch-up immunisation within 30 days from campaign onset. Causal

SUBMITTER: Nunez O 

PROVIDER: S-EPMC11803741 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature